Convolutional code encoding method

An encoder and decoder using LDPC-CC (Low Density Parity Check-Convolutional Codes) is disclosed. In the encoder (200), an encoding rate setting unit (250) sets an encoding rate (s1)/s (s=z), and an information creating unit (210) sets information including from information Xs,i to information Xz1,i to zero. A first information computing unit (220-1) receives information X1,i at time point i to compute the X1(D) term of formula (1). A second information computing unit (220-2) receives information X2,i at time point i to compute the X2(D) term of formula (1). A third information computing unit (220-3) receives information X3,i at time point i to compute the X3(D) term of formula (1). A parity computing unit (230) receives parity Pi1 at time point i1 to compute the P(D) of formula (1). The exclusive OR of the results of the computation is obtained as parity Pi at time i. Ax.

Transmitter Apparatus, Receiver Apparatus, and Wireless Communication Method

When space-time block code signals are to be transmitted, the patterns thereof are changed in accordance with data to be transmitted. This advantageously allows a good-quality data transmission to be achieved by the space-time block code signals. In addition, since data can be transmitted by use of the patterns of the space-time block code signals, the data transmission efficiency can be improved.

TRANSMISSION METHOD AND TRANSMISSION APPARATUS

Of any one of a transmission method X of transmitting modulated signal A and modulated signal B including the same data from a plurality of antennas and a transmission method Y of transmitting modulated signal A and modulated signal B having different data from the plurality of antennas, a base station apparatus does not change the transmission method during data transmission and changes only the modulation scheme. The base station apparatus transmits modulated signal A and modulated signal B to a communication terminal apparatus using the determined transmission method and modulation scheme. In this way, it is possible to improve data transmission efficiency when transmitting data using the plurality of antennas. 1. A transmission method performed by a transmission apparatus having four antennas comprising:selecting a transmission scheme for transmitting a plurality of transmission signals among a plurality of transmission schemes according to a number of a plurality of antennas used for a transmission;selecting a modulation scheme among a plurality of modulation schemes according to the number of a plurality of antennas used for a transmission;modulating the plurality of transmission signals using the selected modulation scheme;outputting a plurality of modulated transmission signals; andtransmitting the plurality of modulated transmission signals using the plurality of antennas used for the transmission among the four antennas, wherein selecting, when the four antennas are used for the transmission, a modulating scheme in which a maximum value of a number of modulated M-ary index of the selected modulation scheme is smaller than a maximum value of a number of modulated M-ary index of the modulation scheme selected when two antennas among the four antennas are used for the transmission, and', 'selecting, when the two antennas are used for the transmission, a modulating scheme having a same maximum value of a number of modulated M-ary index for the every selected ...

Communication apparatus and communication method

Modulated signal A is transmitted from a first antenna, and modulated signal B is transmitted from a second antenna. As modulated signal B, modulated symbols S2(i) and S2(i+1) obtained from different data are transmitted at time i and time i+1 respectively. In contrast, as modulated signal A, modulated symbols S1(i) and S1(i) obtained by changing the signal point arrangement of the same data are transmitted at time i and time i+1 respectively. As a result the reception quality can be changed intentionally at time i and time i+1, and therefore using the demodulation result of modulated signal A of a time when the reception quality is good enables both modulated signals A and B to be demodulated with good error rate performances.

Communication apparatus and communication method

Modulated signal A is transmitted from a first antenna, and modulated signal B is transmitted from a second antenna. As modulated signal B, modulated symbols S2(i) and S2(i+1) obtained from different data are transmitted at time i and time i+1 respectively. In contrast, as modulated signal A, modulated symbols S1(i) and S1(i) obtained by changing the signal point arrangement of the same data are transmitted at time i and time i+1 respectively. As a result the reception quality can be changed intentionally at time i and time i+1, and therefore using the demodulation result of modulated signal A of a time when the reception quality is good enables both modulated signals A and B to be demodulated with good error rate performances.

Transmission apparatus, transmission method, reception apparatus, and reception method

A multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) transmission and reception apparatus is provided which allows high accuracy estimation of frequency offset, high accuracy estimation of a transmission path fluctuation and high accuracy synchronization/signal detection. A mapping section generates a plurality of OFDM signals. In these OFDM signals, some pilot carriers are assigned to the same carrier position, and orthogonal sequences are assigned to the same time slot in the same carrier position.

Transmission method and transmission apparatus

A transmission apparatus includes a plurality of antennas and a transmission scheme determination processor that selects one of either a first transmission scheme of transmitting a plurality of signals including a first amount of data in a frame, respectively, from the plurality of antennas, and a second transmission scheme of transmitting a plurality of signals including a second greater amount of data in a frame, respectively, from the plurality of antennas. The apparatus includes a modulation scheme selection processor that selects a modulation scheme among a plurality of modulation schemes and a control processor that controls the transmission scheme determination processor and the modulation scheme selection processor to change the transmission scheme less frequently than the modulation scheme. A transmitter transmits from the plurality of antennas a signal generated based on the selected transmission scheme and the selected modulation scheme.

TRANSMISSION AND RECEPTION SIGNAL PROCESSOR AND METHOD

A transmission apparatus includes a plurality of orthogonal frequency division multiplexing (OFDM) modulation signal generators, which generate a first OFDM modulation signal and a second OFDM modulation signal. The transmission apparatus also includes a transmitter that transmits the first OFDM modulation signal from a first antenna and the second OFDM modulation signal from a second antenna, in an identical frequency band. A reception apparatus is provided, which includes a plurality of antennas that receive a plurality of OFDM modulation signals; a plurality of OFDM demodulators that transform the plurality of OFDM modulation signals to a plurality of reception signals using Fourier transform; an estimator that outputs a distortion estimation signal using one or more symbols for demodulation included in the plurality of reception signals; and a demodulator that compensates for distortion of the reception signals using the distortion estimation signal and demodulates a data symbol included in the reception signals.

METHOD OF DEMODULATING MODULATION SIGNALS

A method of generating modulation signals is disclosed including generally three steps. A plurality of modulation signals are generated, each of which is to be transmitted from a different one of a plurality of antennas in an identical frequency band, wherein each modulation signal includes a pilot symbol sequence including a plurality of pilot symbols used for demodulation. Each of the pilot symbol sequences is inserted at the same temporal point in each modulation signal, wherein the pilot symbol sequences are orthogonal to each other with zero mutual correlation among the plurality of modulation signals, each pilot symbol having a non-zero amplitude, the quantity of the plurality of pilot symbols in each sequence being greater than the quantity of the plurality of modulation signals to be transmitted. The plurality of modulation signals each including different transmission data and one of the pilot symbol sequences are output to the antennas.

RECEPTION APPARATUS

A reception apparatus includes a plurality of antennas for receiving modulation signals of channels in the same frequency band, an received signal strength intensity estimation unit for estimating the reception received signal strength intensity of each reception signal, transmission path fluctuation estimation units for estimating a transmission path fluctuation of each channel of the reception signal, phase difference estimation units for calculating a phase difference of the transmission path fluctuation estimation signal of a predetermined channel of each antenna and outputting it as a phase difference signal, and a signal selection unit for selecting and outputting a reception quadrate baseband signal for isolating a signal of each channel from the reception signals and a transmission path fluctuation estimation signal of each channel. Thus, by isolating and demodulating a plurality of muliplexed modulated signals received, it is possible to improve the data transmission rate.

Transmission method, transmission apparatus, and reception apparatus

A transmission method for transmitting modulation signals of a plurality of channels to the same frequency band from a plurality of antennas. At the time when a symbol used for demodulation is inserted in a channel, in another channel symbol, the same phase and quadrature signals in the in-phase-quadrature plane are made to be zero signals. Thus, a plurality of modulation signals are multiplexed and transmitted and the transmitted multiplexed modulation signals are demultiplexed and demodulated at a reception apparatus, thereby improving the data transmission rate.

Reception apparatus and associated method of receiving encoded data

A transmission apparatus includes an encoder that codes a data sequence with a parity check matrix, wherein the data sequence includes a final information bit sequence and virtual information bits, and outputs the final information bit sequence and a parity sequence, as LDPC codes, and a transmitter that transmits the LDPC codes as a transmission data. A column length of the parity check matrix is longer than a total length of the final information bit sequence and the parity sequence, by a length of the virtual information bits that are set to “0” and are not transmitted. The total length of the final information bit sequence and the parity sequence has a sequence length corresponding to a length from a first column to a predetermined column of the parity check matrix. The encoder generates the LDPC codes by using the first column to the predetermined column among one or more column(s) of the parity check matrix.

Transmission device, reception device and radio communication method

A transmitting apparatus includes a first OFDM modulator that generates a first OFDM modulation signal by modulating a first information signal using a first modulation scheme, the first OFDM modulation signal having a plurality of subcarriers. A second OFDM modulator generates a second OFDM modulation signal by modulating a second information signal using the first modulation scheme, the second OFDM modulation signal having a plurality of subcarriers, and that generates a third OFDM modulation signal by changing a second position in an in-phase quadrature-phase plane in which a signal point of the second OFDM modulation signal is positioned, to a third position, the third position being different from a first position in the in-phase quadrature-phase plane in which a signal point of the first OFDM modulation signal is positioned. A multiplexer generates a multiplexed signal to be transmitted in a common frequency band, by multiplexing the first OFDM modulation signal and the third modulation ...

Multi-antenna reception apparatus, multi-antenna reception method, multi-antenna transmission apparatus and multi-antenna communication system

Soft decision sections (503, 506) provisionally decide each modulated signal (502, 505) separated using an inverse matrix calculation of a channel fluctuation matrix at separation section (501). Signal point reduction sections (508, 510, 514, 516) reduce candidate signal points of a multiplexed modulated signal using the provisional decision results (504, 507). Soft decision sections (512, 518) make a correct decision using the reduced candidate signal points and obtain received data (RA, RB) of each modulated signal. This allows received data RA, RB with a good error rate characteristic to be obtained with a relatively small number of calculations without reducing data transmission efficiency.

Encoder, decoder, transmitting apparatus, and receiving apparatus

There is provided an encoder that provides a termination sequence with a simple structure for LDPC-CC encoding and reduces an amount of the termination sequence transmitted to a transmission line. The LDPC-CC encoder connects a first encoder to a second encoder to perform encoding and thereby carry out LDPC-CC encoding, the first encoder performing encoding based on an partial parity check matrix for information bits obtained by extracting a sequence corresponding to the information bits in a parity check matrix and the second encoder performing encoding based on a partial parity check matrix for parity bits obtained by extracting a sequence corresponding to the parity bits in the parity check matrix. A termination sequence generator generates a termination sequence including the same number of bits as the memory length of the first encoder and provides the generated termination sequence as an input sequence.

Transmission apparatus and method, and reception apparatus and method

Modulated signal A is transmitted from a first antenna, and modulated signal B is transmitted from a second antenna. As modulated signal B, modulated symbols S2(i) and S2(i+1) obtained from different data are transmitted at time i and time i+1 respectively. In contrast, as modulated signal A, modulated symbols S1(i) and S1(i)′ obtained by changing the signal point arrangement of the same data are transmitted at time i and time i+1 respectively. As a result the reception quality can be changed intentionally at time i and time i+1, and therefore using the demodulation result of modulated signal A of a time when the reception quality is good enables both modulated signals A and B to be demodulated with good error rate performances.

Radio transmitting apparatus and radio transmission method

A radio transmitting apparatus that has a plurality of antennas and changes the number of modulated signals transmitted simultaneously according to the propagation environment and so forth. A transmission power changing section 12 of a radio transmitting apparatus of the present invention adjusts the pilot symbol signal level so as to match the data symbol composite signal level according to the number of transmit modulated signals set by a modulated signal number setting section 11. By this means, the operating range of received pilot, symbols and the operating range of received data symbols become approximately the same on the receiving side, enabling pilot symbol quantization error to be reduced. As a result, the precision of radio wave propagation environment estimation, time synchronization, and frequency offset estimation using pilot symbols improves, and consequently data reception quality improves.

Communication Apparatus and Communication Method

Modulated signal A is transmitted from a first antenna, and modulated signal B is transmitted from a second antenna. As modulated signal B, modulated symbols S2(i) and S2(i+1) obtained from different data are transmitted at time i and time i+1 respectively. In contrast, as modulated signal A, modulated symbols S1(i) and S1(i) obtained by changing the signal point arrangement of the same data are transmitted at time i and time i+1 respectively. As a result the reception quality can be changed intentionally at time i and time i+1, and therefore using the demodulation result of modulated signal A of a time when the reception quality is good enables both modulated signals A and B to be demodulated with good error rate performances.

Methods and apparatus for transmitting modulation signals

A plurality of modulation signals is generated. Each of the plurality of modulation signals includes a pilot symbol sequence having a plurality of pilot symbols. Each pilot symbol sequence is inserted at a same temporal point in each modulation signal, and each pilot symbol in the pilot symbol sequence has a non-zero amplitude. A quantity of the plurality of pilot symbols in each pilot symbol sequence is greater than or equal to a quantity of the plurality of modulation signals to be transmitted. The plurality of modulation signals are transmitted in an identical frequency band from a plurality of antennas. Each of the transmitted plurality of modulation signals includes transmission data and one of the pilot symbol sequences.

Digital reception apparatus

A digital reception apparatus includes a receiver that performs reception processing on a received signal and an adjuster that adjusts the amplitude of the received signal after the reception processing. A distortion estimator estimates a non-linear distortion of the received signal after the reception processing, the non-linear distortion being caused by the reception processing. A distortion corrector performs a distortion correction on the estimated non-linear distortion. A controller controls the adjuster based on a gain control signal such that the amplitude of a desired signal contained in the received signal after the reception processing and the distortion correction approaches a required level. The distortion estimator estimates the non-linear distortion of the received signal with reference to the gain control signal.

Transmitting apparatus, transmission method and signal generating apparatus

A transmitting apparatus and method transmits different modulated signals from a plurality of antennas, and employs a configuration that includes a modulation section that obtains a modulated signal by performing signal point mapping of transmit bits using a signal point arrangement that is divided into a plurality of signal point sets on the IQ plane, whereby the minimum distance between signal points within a signal point set is smaller than the minimum signal point distance between signal point sets; and an antenna that transmits a modulated signal obtained by the modulation section. A signal point generating apparatus generates a first and second symbols to be transmitted by first and second antennas, respectively.

Radio communication apparatus

In a radio communication method whereby adaptive modulation is performed, a method is used whereby pilot symbol signal points are arranged in the in-phase-quadrature plane (IQ plane) so that the reception sensitivity of a receiving apparatus is made optimal in the respective modulation methods while maintaining the average transmission output power of the transmitting apparatus at a fixed level. By this means, it is possible to arrange pilot symbol signal points and improve the reception sensitivity characteristics of a receiving apparatus while maintaining the average transmission output power of the transmitting apparatus at a fixed level.

Transmission apparatus and reception apparatus

A transmitter apparatus wherein a relatively simple structure is used to suppress burst errors without changing the block sizes of encoded blocks even when the number of modulation multi-values is increased. An encoding part subjects transport data to a block encoding process to form block encoded data. A modulating part modulates the block encoded data to form data symbols; and an arranging (interleaving) part arranges(interleaves) the block encoded data in such a manner that the intra-block encoded data of the encoded blocks, which include their respective single different data symbol, get together, and then supplies the arranged(interleaved) block encoded data to the modulating part. In this way, there can be provided a transmitter apparatus wherein a relatively simple structure is used to suppress burst errors without changing the block sizes of encoded blocks even when the number of modulation multi-values is increased.

TRANSMISSION APPARATUS, TRANSMISSION METHOD, RECEPTION APPARATUS, AND RECEPTION METHOD

A MIMO-OFDM transmission and reception apparatus is provided which allows high accuracy estimation of frequency offset, high accuracy estimation of a transmission path fluctuation and high accuracy synchronization/signal detection. A mapping section generates a plurality of OFDM signals. In these OFDM signals, some pilot carriers are assigned to the same carrier position and orthogonal sequences are assigned to the same time slot in the same carrier position. 1. A transmission apparatus comprising:an OFDM signal generator that generates an OFDM signal using either a first OFDM signal transmission method of generating a first OFDM signal including a first pilot carrier and a second pilot carrier, and a second OFDM signal including a third pilot carrier and a fourth pilot carrier, or a second OFDM signal transmission method of generating a third OFDM signal including a fifth pilot carrier and a sixth pilot carrier; anda transmitter that transmits the first OFDM signal from a first antenna, and the second OFDM signal from a second antenna in a same frequency and a same transmission period as the first OFDM signal, or transmits the third OFDM signal from the first antenna,wherein: a first pilot symbol sequence in the first pilot carrier during a first time period;', 'a second pilot symbol sequence in the second pilot carrier during the first time period;', 'a third pilot symbol sequence in the third pilot carrier during the first time period; and', 'a fourth pilot symbol sequence in the fourth pilot carrier during the first time period;, 'the OFDM signal generator arrangesthe first pilot carrier and the third pilot carrier are in a same carrier position in the OFDM signal;the second pilot carrier and the fourth pilot carrier are in a same carrier position in the OFDM signal;the first pilot symbol sequence is a symbol sequence orthogonal to the third pilot symbol sequence; andthe third pilot symbol sequence is a symbol sequence different from the first pilot symbol ...

Transmission apparatus, reception apparatus, transmission method, and reception method

In a communication system in which propagation path error tolerance is improved by switching the modulation method or error correction method adaptively according to the state of the propagation path, signals MX, MY, CX, and CY indicating the modulation method and error correction method used by the transmitting side are transmitted arranged at discrete locations within the same frame. By this means, the possibility of discretely arranged signals MX and MY, or CX and CY, both degrading is made low even if the transmit signal experiences fading or propagation path fluctuations. As a result, it is possible for the modulation method information signal and/or error correction method information signal to be restored correctly on the receiving side.

Transmission method, transmitter apparatus and reception method

A transmitter apparatus wherein a simple structure is used to successfully suppress the degradation of error rate performance that otherwise would be caused by fading or the like. There are included encoding parts (11-1-11-4) that encode transport data; a mapping part (3304) that performs such a mapping that encoded data sequentially formed by the encoding parts (11-1-11-4) are not successively included in the same symbol, thereby forming data symbols; and a symbol interleaver (3301) that interleaves the data symbols. In this way, a low computational complexity can be used to perform an interleaving process equivalent to a bit interleaving process to effectively improve the reception quality at a receiving end.

Transmission device, reception device, and radio communication method

A transmitting apparatus includes an OFDM modulator that generates a first modulation symbol by modulating a first information signal using a first modulation scheme, a signal point of the first modulated information signal being arranged at a first position in an in-phase quadrature-phase plane and a second modulation symbol by modulating a second information signal using the first modulation scheme, and by changing a second position at which a signal point of the modulated second information signal is arranged to a third position in the in-phase quadrature-phase plane, wherein the third position is different from the first position. An OFDM modulation signal includes the first modulation symbol and the second modulation symbol, wherein the OFDM modulation signal comprises a plurality of subcarriers. A transmitter transmits the OFDM modulation signal.

Communication method, and transmitting apparatus and receiving apparatus using that communication method

A transmission method for transmitting an orthogonal frequency division multiplexing signal. The method includes composing a plurality of carrier groups each including one or more subcarriers and assigning transmission data for a plurality of transmission destination terminals, to the plurality of carrier groups, on a basis of one carrier group for one transmission destination terminal basis. The method further includes selecting, for each of the carrier groups, one of a first frame configuration where the transmission data is transmitted using one modulated signal, and a second frame configuration where the transmission data is transmitted using a plurality of modulated signals and transmitting the assigned transmission data of the plurality of transmission destination terminals at a same time on a time axis.

Transmission signal generation apparatus, transmission signal generation method, reception signal apparatus, and reception signal method

Multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) communication is provided which allows high accuracy estimation of frequency offset, high accuracy estimation of a transmission path fluctuation and high accuracy synchronization/signal detection. Pilot symbol mapping is provided for forming pilot carriers by assigning orthogonal sequences to corresponding subcarriers among OFDM signals which are transmitted at the same time from respective antennas in the time domain. Even when pilot symbols are multiplexed among a plurality of channels (antennas), this allows frequency offset/phase noise to be estimated with high accuracy.

Data transmitting apparatus, radio communication system and radio communication method

Before confidential information is transmitted, a radio propagation path environment shared only between a first radio station that is the confidential information transmitting side and a second radio station that is the receiving side is estimated by performing transmission and reception of a signal between the first and second radio stations, and confidential information is transmitted from the first radio station to the second radio station taking this radio propagation path environment into consideration.

Output signal generating method, decoded data generating method, output signal generating apparatus, and decoded data generating apparatus

A transmitter apparatus wherein a simple structure is used to successfully suppress the degradation of error rate performance that otherwise would be caused by fading or the like. There are included encoding parts that encode transport data; a mapping part that performs such a mapping that encoded data sequentially formed by the encoding parts are not successively included in the same symbol, thereby forming data symbols; and a symbol interleaver that interleaves the data symbols. In this way, a low computational complexity can be used to perform an interleaving process equivalent to a bit interleaving process to effectively improve the reception quality at a receiving end.

Radio transmitting apparatus and radio transmission method

A radio transmitting apparatus that has a plurality of antennas and changes the number of modulated signals transmitted simultaneously according to the propagation environment and so forth. A transmission power changing section 12 of a radio transmitting apparatus of the present invention adjusts the pilot symbol signal level so as to match the data symbol composite signal level according to the number of transmit modulated signals set by a modulated signal number setting section 11. By this means, the operating range of received pilot symbols and the operating range of received data symbols become approximately the same on the receiving side, enabling pilot symbol quantization error to be reduced. As a result, the precision of radio wave propagation environment estimation, time synchronization, and frequency offset estimation using pilot symbols improves, and consequently data reception quality improves.

TRANSMISSION AND RECEPTION SIGNAL PROCESSOR AND METHOD

A transmission apparatus includes a plurality of orthogonal frequency division multiplexing (OFDM) modulation signal generators, which generate a first OFDM modulation signal and a second OFDM modulation signal. The transmission apparatus also includes a transmitter that transmits the first OFDM modulation signal from a first antenna and the second OFDM modulation signal from a second antenna, in an identical frequency band. A reception apparatus is provided, which includes a plurality of antennas that receive a plurality of OFDM modulation signals; a plurality of OFDM demodulators that transform the plurality of OFDM modulation signals to a plurality of reception signals using Fourier transform; an estimator that outputs a distortion estimation signal using one or more symbols for demodulation included in the plurality of reception signals; and a demodulator that compensates for distortion of the reception signals using the distortion estimation signal and demodulates a data symbol included in the reception signals. 1. A transmission apparatus comprising:(a) orthogonal frequency division multiplexing (OFDM) modulation signal generating circuitry which, in operation, generatesa first OFDM modulation signal by:(i) inserting symbols for demodulation in a first plurality of subcarriers at a first time and in a second plurality of sub-carriers at a second time adjacent to the first time, the symbols for demodulation being reception processing reference symbols of a reception apparatus;(ii) inserting symbols, having both an in-phase (I) component and a quadrature-phase (Q) component in an I-Q plane of zero, in the second plurality of sub-carriers at the first time and in the first plurality of sub-carriers at the second time; and(iii) inserting first data symbols in the first plurality of sub-carriers at a third time adjacent to the second time and in the second plurality of sub-carriers at the third time;and a second OFDM modulation signal by:(iv) inserting the symbols ...

ENCODING DEVICE AND DECODING DEVICE

Disclosed are an encoding device and a decoding device which can effectively reduce the decoding failure frequency in LDPC encoding/decoding. A loss correction encoding device (120) includes a padding unit (121) which adds a padding packet to an information packet sequence; an interleave unit (122) which rearranges the padding packet and the information packet; and a loss correction encoding unit (123) which performs loss correction encoding for the packet string after the interleave. The interleave unit (122) rearranges the padding packet and the information packet according to variable nodes constituting a minimum stopping set of the inspection matrix which defines a low-density parity inspection code. The interleave unit (122) uses such a rearrangement pattern that avoids a loss correction failure by the minimum stopping set of the LDPC inspection matrix so as to reduce the probability of the loss correction failure by the minimum stopping set.

Apparatus and method for digital wireless communications

A digital wireless communication apparatus includes a first modulator that modulates a pilot symbol according to a first modulation scheme, and a second modulator that modulates specific symbols according to a second modulation scheme, the second modulation scheme being different than the first modulation scheme. A third modulator modulates symbols other than the pilot symbol and the specific symbols according to a third modulation scheme, the third modulation scheme being different than the first and second modulation schemes. A timing controller controls timing such that the specific symbols are inserted immediately before and after the pilot symbol. The signal points of the specific symbols are allocated on an imaginary line that connects the origin point and a signal point of the pilot symbol on a signal space diagram.

RADIO TRANSMITTING APPARATUS AND RADIO TRANSMISSION METHOD

A radio transmitting apparatus that has a plurality of antennas and changes the number of modulated signals transmitted simultaneously according to the propagation environment and so forth. A transmission power changing section 12 of a radio transmitting apparatus of the present invention adjusts the pilot symbol signal level so as to match the data symbol composite signal level according to the number of transmit modulated signals set by a modulated signal number setting section 11. By this means, the operating range of received pilot symbols and the operating range of received data symbols become approximately the same on the receiving side, enabling pilot symbol quantization error to be reduced. As a result, the precision of radio wave propagation environment estimation, time synchronization, and frequency offset estimation using pilot symbols improves, and consequently data reception quality improves.

Transmitter apparatus, receiver apparatus, and wireless communication method

When space-time block code signals are to be transmitted, the patterns thereof are changed in accordance with data to be transmitted. This advantageously allows a good-quality data transmission to be achieved by the space-time block code signals. In addition, since data can be transmitted by use of the patterns of the space-time block code signals, the data transmission efficiency can be improved.

Method for digital wireless communications

In a multivalue modulation type with one pilot symbol inserted for every 3 or more symbols, signal points of each one symbol immediately before and after a pilot symbol are modulated using a modulation type different from that for pilot symbols. In this way, it is possible to suppress deterioration of the accuracy in estimating the reference phase and amount of frequency offset by pilot symbols and improve the bit error rate characteristic in the signal to noise ratio in quasi-coherent detection with symbols whose symbol synchronization is not completely established.

Transmission method, transmission apparatus, reception method, and reception apparatus

Of any one of transmission method X of transmitting modulated signal A and modulated signal B including the same data from a plurality of antennas and transmission method Y of transmitting modulated signal A and modulated signal B having different data from the plurality of antennas, base station apparatus 201 does not change the transmission method during data transmission and changes only the modulation scheme. Base station apparatus 201 transmits modulated signal A and modulated signal B to communication terminal apparatus 251 using the determined transmission method and modulation scheme. In this way, it is possible to improve data transmission efficiency when transmitting data using the plurality of antennas.

TRANSMISSION SIGNAL GENERATION APPARATUS, TRANSMISSION SIGNAL GENERATION METHOD, RECEPTION SIGNAL APPARATUS, AND RECEPTION SIGNAL METHOD

Multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) communication is provided which allows high accuracy estimation of frequency offset, high accuracy estimation of a transmission path fluctuation and high accuracy synchronization/signal detection. Pilot symbol mapping is provided for forming pilot carriers by assigning orthogonal sequences to corresponding subcarriers among OFDM signals which are transmitted at the same time from respective antennas in the time domain. Even when pilot symbols are multiplexed among a plurality of channels (antennas), this allows frequency offset/phase noise to be estimated with high accuracy. 21. The transmission signal generation apparatus of claim , the circuitry comprising:a mapper configured to generate one or more transmission signals, each transmission signal including a data frame having preamble information, pilot information, and data information.3. The transmission signal generation apparatus of claim 2 , the circuitry comprising: generate for each of the one or more transmission signals a corresponding Orthogonal Frequency Division Multiplexed (OFDM) signal for transmission by a corresponding one of the plurality of antennas by Inverse Fourier transforming each of the transmission signals,', 'arrange the pilot symbol sequences in corresponding pilot carriers, and', 'arrange sets of the pilot carriers in a same carrier position in the OFDM signal., 'an Inverse Fourier transformer configured to41. The transmission signal generation apparatus of claim claim 2 , wherein the plural pilot symbol sequences are all orthogonal to each other.51. The transmission signal generation apparatus of claim claim 2 , wherein the plurality of antennas includes two claim 2 , three claim 2 , or four antennas.6. The transmission signal generation apparatus of claim 2 , wherein each OFDM signal can include multiple preamble sequences and multiple pilot subcarriers.7. The transmission signal generation ...

Transmission apparatus, reception apparatus and digital radio communication method

A transmission apparatus includes a frame configuration determiner that determines a modulation system from among a plurality of modulation systems on a communication situation. A first symbol generator modulates a digital transmission signal according to the modulation system determined by the frame configuration determiner and generates a first symbol, the first symbol comprising a first quadrature baseband signal. A second symbol generator modulates the digital transmission signal according to a predetermined modulation system and generates a second symbol, the second symbol comprising a second quadrature baseband signal.

Low-density parity check convolution code (LDPC-CC) encoder and LDPC-CC decoder

It is possible to provide and an LDPC-CC (Low-Density Parity-Check Convolution Codes) encoder and an LDPC-CC decoder which performs an error correction encoding and decoding while reducing the amount of a termination sequence required for encoding/decoding the LDPC-CC encoding/decoding and suppressing degradation of the transmission efficiency. The LDPC-CC encoder (400) includes a weight control unit (470) which stores a weight pattern (475) based on an LDPC-CC inspection matrix (100); and a weight pattern (476) based on a check matrix (300) obtained by deforming an LDPC-CC inspection matrix (100). The weight control unit (470) controls a weight to be multiplied onto the outputs of a plurality of shift registers (410-1 to 410-M, 430-1 to 430-M) by using the weight pattern (475) when the input bit is an information sequence, and using a weight pattern (476) which makes a weight value to be multiplied by an inspection bit v2,t to be 0 when the input bit is a termination sequence.

Transmission device, reception device, and radio communication method

A transmitting apparatus includes an OFDM modulator that generates a first modulation symbol by modulating a first information signal using a first modulation scheme, a signal point of the first modulated information signal being at a first position in an in-phase quadrature-phase plane. A second modulation symbol by modulating a second information signal using the first modulation scheme, and by changing a second position at which a signal point of the modulated second information signal is arranged to a third position in the in-phase quadrature-phase plane, and an OFDM modulation signal including the first modulation symbol and the second modulation symbol, wherein the OFDM modulation signal comprises a plurality of subcarriers.

TRANSMITTING APPARATUS, TRANSMITTING METHOD, RECEIVING APPARATUS, AND RECEIVING METHOD

Modulated signal A is transmitted from a first antenna, and modulated signal B is transmitted from a second antenna. As modulated signal B, modulated symbols S() and S(+1) obtained from different data are transmitted at time i and time i+1 respectively. In contrast, as modulated signal A, modulated symbols S() and S()′ obtained by changing the signal point arrangement of the same data are transmitted at time i and time i+1 respectively. As a result the reception quality can be changed intentionally at time i and time i+1, and therefore using the demodulation result of modulated signal A of a time when the reception quality is good enables both modulated signals A and B to be demodulated with good error rate performances. 1. A transmitting apparatus comprising:a signal processing section that generates a first modulation symbol sequence by changing an amplitude of a modulation symbol sequence where first transmission data is mapped using a first mapping pattern of a predetermined modulation scheme and generates a second modulation symbol sequence by changing an amplitude and a mapping pattern of a modulation symbol sequence where second transmission data is mapped using the first mapping pattern; anda plurality of antennas that transmit the first modulation symbol sequence and the second modulation symbol sequence, respectively, in a same frequency band and at a same time, wherein:the second modulation symbol sequence is generated using a second mapping pattern where a phase of the first mapping pattern is shifted to a predetermined direction per the second modulation symbol,the first mapping pattern and the second mapping pattern map a signal point on an IQ plane corresponding to a bit set which comprises a plurality of bits,the first mapping pattern maps a first bit set in the plurality of bits on the IQ plane as a first signal point,the second mapping pattern includes a pattern where the first bit set is arranged as a second signal point, andthe first bit set is ...

TRANSMISSION DEVICE

Provided is a transmission device which improves the error rate characteristic upon decoding when performing error correction encoding by using a self-orthogonal code or an LDPC-CC in a communication system using a communication path having a fading fluctuation, multi-value modulation, or MIMO transmission. In the transmission device, the self-orthogonal encoding unit (110) encodes a self-orthogonal code having a constriction length K and an interleave unit (130) rearranges a code word sequence so that the same modulation symbol includes an information bit of a moment i and a non-correlated bit of the information bit of the moment i in a multi-value modulation unit (150).

TRANSMITTER APPARATUS AND MULTIANTENNA TRANSMITTER APPARATUS

A transmitter apparatus wherein a relatively simple structure is used to suppress burst errors without changing the block sizes of encoded blocks even when the number of modulation multi-values is increased. There are included an encoding part (11) that subjects transport data to a block encoding process to form block encoded data; a modulating part (15) that modulates the block encoded data to form data symbols; and an arranging (interleaving) part (12) that arranges (interleaves) the block encoded data in such a manner that the intra-block encoded data of the encoded blocks, which include their respective single different data symbol, get together, and then supplies the arranged (interleaved) block encoded data to the modulating part (15). In this way, there can be provided a transmitter apparatus (10) wherein a relatively simple structure is used to suppress burst errors without changing the block sizes of encoded blocks even when the number of modulation multi-values is increased.

OFDM frame transmission method and apparatus

A transmission method includes generating a plurality of orthogonal frequency division multiplexing (OFDM) signals, each signal including different data and some of the plurality of OFDM signals including pilot symbols. The pilot symbols are assigned to a predetermined subcarrier in predetermined time. At least one of the plurality of OFDM signals is assigned the pilot symbols to the predetermined subcarrier in the predetermined time, and other OFDM signals are assigned data to the predetermined subcarrier in the predetermined time. The method further includes converting each of the plurality of OFDM signals to a radio signal and transmitting each of the radio signals from a different antenna.

Transmitter apparatus and radio communication method

A radio station equipped with an array antenna, when transmitting an information symbol sequence to a particular radio station, uses a plurality of vectors, which are produced based on a propagation channel characteristic established between these radio stations, to simultaneously transmit a plurality of symbol sequences, which include the information symbol sequence, by way of vector multiplexing, thereby causing the particular radio station to receive the information symbol sequence, while causing other radio stations of different propagation channels to simultaneously receive a part or all the plurality of symbol sequences. Thus, when data is transmitted to a particular radio station via a radio communication channel, the concealment of information can be secured with a high level of security.

Transmission and reception apparatus and method

A transmission apparatus includes a plurality of orthogonal frequency division multiplexing (OFDM) modulation signal generators, which generate a first OFDM modulation signal and a second OFDM modulation signal. The transmission apparatus also includes a transmitter that transmits the first OFDM modulation signal from a first antenna and the second OFDM modulation signal from a second antenna, in an identical frequency band. A reception apparatus is provided, which includes a plurality of antennas that receive a plurality of OFDM modulation signals; a plurality of OFDM demodulators that transform the plurality of OFDM modulation signals to a plurality of reception signals using Fourier transform; an estimator that outputs a distortion estimation signal using one or more symbols for demodulation included in the plurality of reception signals; and a demodulator that compensates for distortion of the reception signals using the distortion estimation signal and demodulates a data symbol included ...

Reception apparatus

A reception apparatus includes a plurality of antennas for receiving modulation signals of channels in the same frequency band, an received signal strength intensity estimation unit for estimating the reception received signal strength intensity of each reception signal, transmission path fluctuation estimation units for estimating a transmission path fluctuation of each channel of the reception signal, phase difference estimation units for calculating a phase difference of the transmission path fluctuation estimation signal of a predetermined channel of each antenna and outputting it as a phase difference signal, and a signal selection unit for selecting and outputting a reception quadrate baseband signal for isolating a signal of each channel from the reception signals and a transmission path fluctuation estimation signal of each channel. Thus, by isolating and demodulating a plurality of muliplexed modulated signals received, it is possible to improve the data transmission rate.

Transmission apparatus, reception apparatus and digital radio communication method

A transmission apparatus includes a frame configuration determiner that determines a modulation scheme, from among a plurality of modulation schemes. A first symbol generator modulates a transmission signal according the modulation scheme determined by the frame configuration determiner to generate a first symbol, the first symbol being a first quadrature baseband signal. A second symbol generator modulates a pilot signal in accordance with a specific modulation scheme to generate a second symbol. A third symbol generator generates a third symbol to be inserted immediately before or immediately after the second symbol, the third symbol being different from the first symbol. On a signal space diagram, the third symbol generator arranges a signal point of the third symbol on a virtual line that links an origin with a signal point of the second symbol.

Communication method, and transmitting apparatus and receiving apparatus using that communication method

A transmission apparatus includes a plurality of antennas and a frame configurator that selects, in a first unit time either a first transmitting method which transmits a modulated signal from at least one of the plurality of antennas, or a second transmitting method which transmits a plurality of modulated signals from the plurality of antennas, for a first carrier group arranged for a first terminal and either the first transmitting method or the second transmitting method for a second carrier group arranged for a second terminal. The frame configurator selects, in a second unit time either the first transmitting method or the second transmitting method for the first carrier group arranged for a third terminal and either the first transmitting method or the second transmitting method for the second carrier group arranged for a fourth terminal, wherein each of carrier groups includes one or more sub-carriers.

Methods and apparatus for transmitting modulation signals

A plurality of multicarrier signals is generated. Each of the plurality of multicarrier signals includes a pilot symbol sequence at a same temporal point in each multicarrier signal. Each pilot symbol sequence includes a plurality of pilot symbols with non-zero amplitude. The pilot symbol sequences are orthogonal to each other at the same temporal point. A quantity of the plurality of pilot symbols in each pilot symbol sequence is greater than or equal to a quantity of the plurality of multicarrier signals to be transmitted. The plurality of multicarrier signals are transmitted in an identical frequency band from a plurality of antennas. The plurality of antennas includes two, three, or four antennas.

Transmitter apparatus and multiantenna transmitter apparatus

A transmitter apparatus wherein a relatively simple structure is used to suppress burst errors without changing the block sizes of encoded blocks even when the number of modulation multi-values is increased. There are included an encoding part (11) that subjects transport data to a block encoding process to form block encoded data; a modulating part (15) that modulates the block encoded data to form data symbols; and an arranging (interleaving) part (12) that arranges (interleaves) the block encoded data in such a manner that the intra-block encoded data of the encoded blocks, which include their respective single different data symbol, get together, and then supplies the arranged (interleaved) block encoded data to the modulating part (15). In this way, there can be provided a transmitter apparatus (10) wherein a relatively simple structure is used to suppress burst errors without changing the block sizes of encoded blocks even when the number of modulation multi-values is increased.

Multi-antenna reception apparatus, multi-antenna reception method, multi-antenna transmission apparatus and multi-antenna communication system

Soft decision sections (503, 506) provisionally decide each modulated signal (502, 505) separated using an inverse matrix calculation of a channel fluctuation matrix at separation section (501). Signal point reduction sections (508, 510, 514, 516) reduce candidate signal points of a multiplexed modulated signal using the provisional decision results (504, 507). Soft decision sections (512, 518) make a correct decision using the reduced candidate signal points and obtain received data (RA, RB) of each modulated signal. This allows received data RA, RB with a good error rate characteristic to be obtained with a relatively small number of calculations without reducing data transmission efficiency.

Transmitting apparatus, receiving apparatus, transmission method, and reception method

A transmission frame generating device generates a transmission frame. The generating device includes a control information signal generator which generates a modulation method control signal indicating a modulation method used for a data signal and an error correction method control signal indicating an error correction method used for the data signal and a frame former which forms the transmission frame by arranging a training signal, the data signal, the modulation method control signal and the error correction method control signal on a plurality of subcarriers on a frequency axis. The modulation method control signal being repeatedly and discretely arranged on a first multiple of the plurality of subcarriers on the frequency axis and the error correction method control signal being repeatedly and discretely arranged on a second multiple of the plurality of the subcarriers on the frequency axis.

ENCODING METHOD, ENCODER, AND DECODER

A low-density parity check convolution code (LDPC-CC) is made, and a signal sequence is sent after subjected to an error-correcting encodement using the low-density parity check convolution code. In this case, a low-density parity check code of a time-variant period (3g) is created by linear operations of first to 3g-th (letter g designates a positive integer) parity check polynomials and input data.

Apparatus and method for digital wireless communications

In a multivalue modulation type with one pilot symbol inserted for every 3 or more symbols, signal points of each one symbol immediately before and after a pilot symbol are modulated using a modulation type different from that for pilot symbols. In this way, it is possible to suppress deterioration of the accuracy in estimating the reference phase and amount of frequency offset by pilot symbols and improve the bit error rate characteristic in the signal to noise ratio in quasi-coherent detection with symbols whose symbol synchronization is not completely established.

Method for digital wireless communications

In a multivalue modulation type with one pilot symbol inserted for every 3 or more symbols, signal points of each one symbol immediately before and after a pilot symbol are modulated using a modulation type different from that for pilot symbols. In this way, it is possible to suppress deterioration of the accuracy in estimating the reference phase and amount of frequency offset by pilot symbols and improve the bit error rate characteristic in the signal to noise ratio in quasi-coherent detection with symbols whose symbol synchronization is not completely established.

Radio communication apparatus capable of switching modulation schemes

A radio communication apparatus that is capable of switching modulation schemes. The radio communication apparatus includes a QPSK modulation signal generator, a QAM modulation signal generator, a transmission radio, and a common transmission power amplifier. The QPSK modulation signal generator modulates transmission data by a QPSK modulation scheme and outputs a QPSK modulation signal. The QAM modulation signal generator modulates transmission data by a QAM scheme and outputs a QAM modulation signal. The transmission radio receives the QPSK modulation signal or the QAM modulation signal and outputs a transmission signal, which is amplified by the common transmission power amplifier. The QPSK modulation signal generator and the QAM modulation signal generator each output signal component that make an average transmission power of the QAM modulation signal in the common transmission power amplifier smaller than an average transmission power of the QPSK modulation signal in the common transmission ...

Transmitter apparatus and multiantenna transmitter apparatus

A transmitter apparatus wherein a relatively simple structure is used to suppress burst errors without changing the block sizes of encoded blocks even when the number of modulation multi-values is increased. An encoding part subjects transport data to a block encoding process to form block encoded data. A modulating part modulates the block encoded data to form data symbols; and an arranging (interleaving) part arranges(interleaves) the block encoded data in such a manner that the intra-block encoded data of the encoded blocks, which include their respective single different data symbol, get together, and then supplies the arranged(interleaved) block encoded data to the modulating part. In this way, there can be provided a transmitter apparatus wherein a relatively simple structure is used to suppress burst errors without changing the block sizes of encoded blocks even when the number of modulation multi-values is increased.

Radio communication apparatus capable of switching modulation schemes

A radio communication apparatus capable of switching modulation schemes includes a QPSK modulation signal generator configured to modulate transmission data by a QPSK modulation scheme and to output a QPSK modulation signal. A 64QAM modulation signal generator is configured to modulate transmission data by a 64QAM scheme and to output a 64QAM modulation signal. A radio processor is configured to receive, as an input, the QPSK modulation signal or the 64 QAM modulation signal and to output a transmission signal. A transmission power amplifier is configured to amplify a power of the transmission signal. The QPSK modulation signal generator and the 64QAM modulation signal generator perform gain control so as to make an average transmission power of the 64QAM modulation signal smaller than an average transmission power of the QPSK modulation signal.

Decoding method and decoding apparatus

A decoding device allowing a high-speed decoding operation. In a decoding section (215), if a degree of a check equation by a check matrix is D and the relationship between the check equation of the j+first row of the check matrix and the cheek equation of the jth row is shifted by n-bit, row processing operation sections (405#1 to 405#3) and column processing operation sections (410#1 to 410#3) perform the operation of a protograph in which the columns of the check matrix are delimited for each "(D+1)×N (N: natural number)," and the rows of the check matrix are delimited for each "(D+1)×N/n," and formed as the processing unit of the row processing operation and column processing operation.

Transmission apparatus, reception apparatus and digital radio communication method

Frame configuration determination section 101 judges a communication situation based on the transmission path information indicating the level of fluctuations of the transmission path due to fading and data transmission speed information indicating the transmission speed of the transmission data based on the level of the reception signal and determines the interval of inserting a known pilot symbol and the modulation system of a transmission digital signal. Quadrature baseband modulation section 102 modulates the transmission digital signal to a quadrature baseband signal according to the modulation system indicated from frame configuration determination section 101 . Pilot symbol generation section 103 generates a pilot symbol known between the transmitting and receiving sides. Frame configuration section 104 inserts the known pilot symbol output from pilot symbol generation section 103 at the insertion interval instructed from frame configuration determination section 101 to configure ...

TRANSMISSION METHOD, TRANSMISSION APPARATUS, AND RECEPTION APPARATUS

A transmission method for transmitting modulation signals of a plurality of channels to the same frequency band from a plurality of antennas. At the time when a symbol used for demodulation is inserted in a channel, in another channel symbol, the same phase and quadrature signals in the in-phase-quadrature plane are made to be zero signals. Thus, a plurality of modulation signals are multiplexed and transmitted and the transmitted multiplexed modulation signals are demultiplexed and demodulated at a reception apparatus, thereby improving the data transmission rate. 1. A method of receiving modulation signals , the method comprising: wherein each of the pilot symbol sequences being inserted at the same temporal points in the each modulation signal, and', 'wherein the pilot symbol sequences are orthogonal to each other with zero cross correlation among the plurality of modulation signals, each pilot symbol having a non-zero amplitude, the quantity of the plurality of pilot symbols in each sequence being greater than the quantity of the plurality of transmitted modulation signals;, 'receiving a plurality of multiplexed modulation signals each of which being transmitted from a plurality of antennas of a communication partner, wherein each modulation signal includes a pilot symbol sequence consisting of a plurality of pilot symbols used for demodulation,'}estimating a transmission path distortion of the each modulation signal based on the plurality of received multiplexed modulation signals; anddemodulating the each modulation signal including the plurality of received multiplexed modulation signals using the transmission path distortion.2. The method of claim 1 , wherein the plurality of pilot symbols used for demodulation are symbols used for estimating a frequency offset.3. The method of claim 1 , wherein the plurality of pilot symbols used for demodulation each comprise a complex number.4. The method of claim 1 , wherein each of the plurality of multiplexed ...

TRANSMISSION AND RECEPTION APPARATUS AND METHOD

A transmission apparatus includes a plurality of orthogonal frequency division multiplexing (OFDM) modulation signal generators, which generate a first OFDM modulation signal and a second OFDM modulation signal. The transmission apparatus also includes a transmitter that transmits the first OFDM modulation signal from a first antenna and the second OFDM modulation signal from a second antenna, in an identical frequency band. A reception apparatus is provided, which includes a plurality of antennas that receive a plurality of OFDM modulation signals; a plurality of OFDM demodulators that transform the plurality of OFDM modulation signals to a plurality of reception signals using Fourier transform; an estimator that outputs a distortion estimation signal using one or more symbols for demodulation included in the plurality of reception signals; and a demodulator that compensates for distortion of the reception signals using the distortion estimation signal and demodulates a data symbol included in the reception signals. 1. A transmission apparatus comprising: [ inserting a first symbol for demodulation in a first plurality of sub-carriers at a first time and in a second plurality of sub-carriers at a second time;', 'inserting a symbol, having both an in-phase (I) component and a quadrature-phase (Q) component in an I-Q plane of zero, in the second plurality of sub-carriers at the first time and in the first plurality of sub-carriers at the second time; and, '(i) generate a first OFDM modulation signal by, inserting a symbol, having both an in-phase (I) component and a quadrature-phase (Q) component in an I-Q plane of zero, in the first plurality of sub-carriers at the first time and in the second plurality of sub-carriers at the second time; and', 'inserting a second symbol for demodulation in the second plurality of sub-carriers at the first time and in the first plurality of sub-carriers at the second time; and, '(ii) generate a second OFDM modulation signal by], '(a ...

COMMUNICATION APPARATUS AND COMMUNICATION METHOD

Modulated signal A is transmitted from a first antenna, and modulated signal B is transmitted from a second antenna. As modulated signal B, modulated symbols S2(i) and S2(i+1) obtained from different data are transmitted at time i and time i+1 respectively. In contrast, as modulated signal A, modulated symbols S1(i) and S1(i) obtained by changing the signal point arrangement of the same data are transmitted at time i and time i+1 respectively. As a result the reception quality can be changed intentionally at time i and time i+1, and therefore using the demodulation result of modulated signal A of a time when the reception quality is good enables both modulated signals A and B to be demodulated with good error rate performances.

Transmitting apparatus, receiving apparatus, transmission method, and reception method

A transmission method includes generating a control information signal relating to control information of a data signal. A transmission frame is formed by repeating and discretely arranging the same control information signal. The data signal and the control information signal are transmitted using the transmission frame.

TRANSMISSION APPARATUS AND ASSOCIATED METHOD OF ENCODED DATA

A transmission apparatus includes an encoder that codes a data sequence with a parity check matrix, wherein the data sequence includes a final information bit sequence and virtual information bits, and outputs the final information bit sequence and a parity sequence, as LDPC codes, and a transmitter that transmits the LDPC codes as a transmission data. A column length of the parity check matrix is longer than a total length of the final information bit sequence and the parity sequence, by a length of the virtual information bits that are set to “0” and are not transmitted. The total length of the final information bit sequence and the parity sequence has a sequence length corresponding to a length from a first column to a determined column of the parity check matrix. The encoder generates the LDPC codes by using the first column to the determined column among one or more column(s) of the parity check matrix. 1. A transmission apparatus applied in an optical communication system , comprising:an encoder, which, in operation, outputs a parity sequence and an information sequence, the parity sequence comprising low-density parity-check (LDPC) encoded data obtained by LDPC-encoding the information sequence using a parity check matrix in which “n” number of (where n is an integer equal to or greater than 1) parity check equation groups including a plurality of parity check polynomials are arranged, each of the plurality of parity check polynomials satisfying zero; anda transmitter, which, in operation, converts a modulation signal obtained by modulating the LDPC encoded data into an optical signal and outputs the optical signal, whereinthe parity sequence is generated by using a first column to a determined column of the parity check matrix for an information sequence having a sequence length that corresponds to a length from the first column to the determined column among one or more column(s) of the parity check matrix that corresponds to n-th parity check equation ...

Transmitting apparatus, receiving apparatus, transmission method, and reception method

A transmitting apparatus controls, for each transmit frame, at least one of a modulation method and an error correction method. The transmitting apparatus forms an information symbol and transmits the information symbol using multiple subcarriers. A modulation method information signal generator generates an information signal relating to a modulation method of the information symbol. An error correction method information signal generator generates an information signal relating to an error correction method of the information symbol. A frame former forms a transmit frame by repeating and discretely arranging at least one of the same modulation method information signal and the same error correction method information signal at the same time within the same frame, and a transmitter transmits the transmit frame.

Method for digital wireless communications

In a multivalue modulation type with one pilot symbol inserted for every 3 or more symbols, signal points of each one symbol immediately before and after a pilot symbol are modulated using a modulation type different from that for pilot symbols. In this way, it is possible to suppress deterioration of the accuracy in estimating the reference phase and amount of frequency offset by pilot symbols and improve the bit error rate characteristic in the signal to noise ratio in quasi-coherent detection with symbols whose symbol synchronization is not completely established.

Communication method, transmitting device using the same, and receiving device using the same

A serial/parallel conversion section 202 converts a channel A transmit digital signal 201 to parallel data with an arrangement in accordance with a frame configuration signal 222. An inverse discrete Fourier transform section 204 performs inverse discrete Fourier transform processing of channel A parallel signal 203. A radio section 206 converts signal 205 to radio frequency. A power amplification section 208 amplifies the power of the transmit signal 207. A serial/parallel conversion section 212 converts a channel B transmit digital signal 211 to parallel data with an arrangement in accordance with frame configuration signal 222. An inverse discrete Fourier transform section 214 performs inverse discrete Fourier transform processing of parallel signal 213. A radio section 216 converts the post-transform signal 215 to radio frequency. A power amplification section 218 amplifies the power of the transmit signal 217.

Radio transmission apparatus and methods

A radio transmission apparatus determines information indicative of an estimated communications channel condition and generates a single modulation signal or a plurality of modulation signals based on the estimated communications channel condition information. The single modulation signal from a first antenna or the plurality of modulation signals is(are) transmitted from the first antenna and a second antenna. The plurality of modulation signals include different information from each other and are transmitted over an identical frequency band and at an identical temporal point. The single modulation signal and the plurality of modulation signals contain parameter information indicating a number of modulation signals transmitted at the same time.

Processor and processing method for signal transmission

A transmission signal processing method is provided, for generating a first OFDM modulation signal and a second OFDM modulation signal which are transmitted in an identical frequency band, by utilizing a first antenna for transmitting the first OFDM modulation signal and by utilizing a second antenna for transmitting the second OFDM modulation signal. The method includes a step of generating the first OFDM modulation signal and the second OFDM modulation signal utilizing a plurality of OFDM modulation signal generators, and a step of outputting the first OFDM modulation signal to the first antenna and the second OFDM modulation signal to the second antenna.

Radio communications apparatus and radio communications method

The invention performs orthogonal frequency division multiplex processing on a transmission signal to form an OFDM modulation signal (daubed in FIG.) and performs orthogonal frequency division multiplex processing and code division multiple access processing on a transmission signal to form an OFDM-CDM modulation signal (shaded in FIG.) to transmit the OFDM modulation signal and the OFDM-CDM modulation signal, which makes it possible to transmit data in a very high rate using the OFDM modulation signal while making it possible to transmit data in a higher quality using the OFDM-CDM modulation signal than using the OFDM—modulation signal, although it is slightly inferior to OFDM modulation in terms of high rate transmission.

Transmission apparatus

A wireless communication system includes an amplitude limiting section that limits an amplitude of a sequence of signals input for transmission and a nonlinear distortion compensating section compensates nonlinear distortion of the sequence of signals output from the amplitude limiting section. A digital wireless communication method is also provided.

RECEPTION DEVICE

It is possible to demodulate a plurality of modulated signals transmitted from a plurality of antennas by using a comparatively small-size circuit with a preferable error ratio characteristic. Partial bit judgment units (509, 512) demodulates partial bits of the 64QAM-modulated signal by modifying which of the bits in the 6-bit strings constituting a symbol is to be demodulated depending on in which region of the IQ plane the reception signal point exists. This improves the partial bit error characteristic judged by the partial bit judgment units (509, 512), which in turn improves reliability of the reduced candidate signal point for use by a likelihood detection unit (518). As a result, it is possible to improve the error ratio characteristic of the final reception digital signals (322, 323).

TRANSMISSION DEVICE, RECEPTION DEVICE, AND RADIO COMMUNICATION METHOD

A transmitting apparatus includes an OFDM modulator that generates a first modulation symbol by modulating a first information signal using a first modulation scheme, a signal point of the first modulated information signal being at a first position in an in-phase quadrature-phase plane. A second modulation symbol by modulating a second information signal using the first modulation scheme, and by changing a second position at which a signal point of the modulated second information signal is arranged to a third position in the in-phase quadrature-phase plane, and an OFDM modulation signal including the first modulation symbol and the second modulation symbol, wherein the OFDM modulation signal comprises a plurality of subcarriers. 1. A transmitting apparatus comprising:an OFDM modulator that generatesa first modulation symbol by modulating a first information signal using a first modulation scheme, a signal point of the first modulated information signal being arranged at a first position in an in-phase quadrature-phase plane,a second modulation symbol by modulating a second information signal using the first modulation scheme, and by changing a second position at which a signal point of the modulated second information signal is arranged to a third position in the in-phase quadrature-phase plane, wherein the third position is different from the first position, an OFDM modulation signal including the first modulation symbol and the second modulation symbol, wherein the OFDM modulation signal comprises a plurality of subcarriers; anda transmitter that transmits the OFDM modulation signal.2. The transmitting apparatus according to claim 1 , wherein the first modulation symbol and the second modulation symbol are arranged in a same subcarrier in the OFDM modulation signal.3. A transmission method comprising:generating a first modulation symbol by modulating a first information signal using a first modulation scheme, a signal point of the first modulated information ...

ENCODING METHOD

An encoder and decoder using LDPC-CC (Low Density Parity Check-Convolutional Codes) is disclosed. The encoder exhibits encoding rates realized with a small circuit-scale and a high data reception quality. In the encoder (), an encoding rate setting unit () sets an encoding rate (s−1)/s (s=z), and an information creating unit () sets information including from information Xs,i to information Xz−1,i to zero. A first information computing unit (-) receives information X1,i at time point i to compute the X1(D) term of formula (1). A second information computing unit (-) receives information X2,i at time point i to compute the X2(D) term of formula (1). A third information computing unit (-) receives information X3,i at time point i to compute the X3(D) term of formula (1). A parity computing unit () receives parity Pi−1 at time point i−1 to compute the P(D) of formula (1). The exclusive OR of the results of the computation is obtained as parity Pi at time i. Ax. 2. The encoding method according to claim 1 , wherein the time varying period of g is 3.3. The encoding method according to claim 2 , wherein{'sub': 'k', 'claim-text': {'br': None, 'i': B', 'D', 'D', '+D, 'sub': 'k', 'sup': b1', 'b2, '()=+1\u2003\u2003(Equation 3)'}, 'B(D) in the parity check polynomial according to equation 1 and the parity check polynomial according to equation 2 is represented as equation 3where (b1 mod 3, b2 mod 3) is equal to (1, 2) or (2, 1), and{'sub': 'k', 'claim-text': {'br': None, 'i': A', 'D', 'D', '+D, 'sub': 'Xr,k', 'sup': ar,k,1', 'ar,k,2, '()=+1\u2003\u2003(Equation 4)'}, 'A(D) in the parity check polynomial according to equation 1 and the parity check polynomial according to equation 2 is represented as equation 4where {(ar, k, 1) mod 3, (ar, k, 2) mod 3} is equal to (1, 2) or (2, 1). The present invention relates to an encoder, decoder and encoding method using a low-density parity-check convolutional code (LDPC-CC) supporting a plurality of coding rates.In recent years, ...

Transmission signal generation apparatus, transmission signal generation method, reception signal generation apparatus, and reception signal generation method

Multiple-Input and Multiple-Output (MIMO)-Orthogonal Frequency Division Multiplexing (OFDM) communication is provided which allows high accuracy estimation of frequency offset, high accuracy estimation of a transmission path fluctuation and high accuracy synchronization/signal detection. Pilot symbol mapping is provided for forming pilot carriers by assigning orthogonal sequences to corresponding subcarriers among OFDM signals which are transmitted at the same time from respective antennas in the time domain. Even when pilot symbols are multiplexed among a plurality of channels (antennas), this allows frequency offset/phase noise to be estimated with high accuracy.

Communication method, transmitting device using the same, and receiving device using the same

A transmission method for transmitting an orthogonal frequency division multiplexing signal the method includes composing, on a per unit time basis, a plurality of carrier groups each composed of one or more subcarriers, assigning, on a per unit time basis, transmission data for a plurality of transmission destination terminals, to the plurality of carrier groups and transmitting the assigned transmission data.

Array antenna apparatus utilizing a nonlinear distortion compensator circuit

Amplitude phase distortion adding sections are provided for the power amplifiers on the antenna arrays greater in amplitude weighting while amplitude distortion adding sections are provided for the power amplifiers on the antenna arrays smaller in amplitude weighting. Due to this, because a required amount of distortion compensation is made based on each antenna array, there is no bad effect upon the adjacent other antenna array, suppressing the deterioration in beam control accuracy. This, also, reduces the size of the apparatus and improves the power efficiency on the array antenna apparatus overall.

Radio communication apparatus capable of switching modulation schemes

A transmitting apparatus, includes a signal generator that generates a modulation signal by modulating transmission data using one of a plurality of modulation schemes, a first modulation scheme having a higher m-ary modulation value than other modulation schemes and a pilot signal generator generates a pilot signal. An orthogonal frequency division multiplexing (OFDM) signal generator generates an OFDM signal by selecting the modulation signal and the pilot signal according to the frame timing signal. The OFDM signal is converted to a radio signal, is amplified and is transmitted to an antenna. The pilot signal is inserted in the OFDM signal per a predetermined OFDM symbol and per a predetermined subcarrier and has a lower amplitude than a maximum amplitude of the first modulation scheme in an in-phase-quadrature (IQ) plane.

COMMUNICATION METHOD, AND TRANSMITTING APPARATUS AND RECEIVING APPARATUS USING THAT COMMUNICATION METHOD

A transmission apparatus includes a plurality of antennas and a frame configurator that selects, in a first unit time either a first transmitting method which transmits a modulated signal from at least one of the plurality of antennas, or a second transmitting method which transmits a plurality of modulated signals from the plurality of antennas, for a first carrier group arranged for a first terminal and either the first transmitting method or the second transmitting method for a second carrier group arranged for a second terminal. The frame configurator selects, in a second unit time either the first transmitting method or the second transmitting method for the first carrier group arranged for a third terminal and either the first transmitting method or the second transmitting method for the second carrier group arranged for a fourth terminal, wherein each of carrier groups includes one or more sub-carriers.

Reception apparatus and associated method of receiving encoded data

A transmission apparatus includes an encoder that codes a data sequence with a parity check matrix, wherein the data sequence includes a final information bit sequence and virtual information bits, and outputs the final information bit sequence and a parity sequence, as LDPC codes, and a transmitter that transmits the LDPC codes as a transmission data. A column length of the parity check matrix is longer than a total length of the final information bit sequence and the parity sequence, by a length of the virtual information bits that are set to 0 and are not transmitted. The total length of the final information bit sequence and the parity sequence has a sequence length corresponding to a length from a first column to a predetermined column of the parity check matrix. The encoder generates the LDPC codes by using the first column to the predetermined column among one or more column(s) of the parity check matrix.

Apparatus and method for digital wireless communications

In a multivalue modulation type with one pilot symbol inserted for every 3 or more symbols, signal points of each one symbol immediately before and after a pilot symbol are modulated using a modulation type different from that for pilot symbols. In this way, it is possible to suppress deterioration of the accuracy in estimating the reference phase and amount of frequency offset by pilot symbols and improve the bit error rate characteristic in the signal to noise ratio in quasi-coherent detection with symbols whose symbol synchronization is not completely established.

Transmission apparatus, reception apparatus and digital radio communication method

A transmission apparatus includes a frame configuration determiner that determines a modulation system from among a plurality of modulation systems on a communication situation. A first symbol generator modulates a digital transmission signal according to the modulation system determined by the frame configuration determiner and generates a first symbol, the first symbol comprising a first quadrature baseband signal. A second symbol generator modulates the digital transmission signal according to a predetermined modulation system and generates a second symbol, the second symbol comprising a second quadrature baseband signal.

Communication apparatus and communication method

Modulated signal A is transmitted from a first antenna, and modulated signal B is transmitted from a second antenna. As modulated signal B, modulated symbols S2(i) and S2(i+1) obtained from different data are transmitted at time i and time i+1 respectively. In contrast, as modulated signal A, modulated symbols S1(i) and S1(i)′ obtained by changing the signal point arrangement of the same data are transmitted at time i and time i+1 respectively. As a result the reception quality can be changed intentionally at time i and time i+1, and therefore using the demodulation result of modulated signal A of a time when the reception quality is good enables both modulated signals A and B to be demodulated with good error rate performances.

Methods and apparatus for transmitting modulation signals

A plurality of modulation signals is generated. Each of the plurality of modulation signals includes a pilot symbol sequence having a plurality of pilot symbols. Each pilot symbol sequence is inserted at a same temporal point in each modulation signal, and each pilot symbol in the pilot symbol sequence has a non-zero amplitude. A quantity of the plurality of pilot symbols in each pilot symbol sequence is greater than or equal to a quantity of the plurality of modulation signals to be transmitted. The plurality of modulation signals are transmitted in an identical frequency band from a plurality of antennas. Each of the transmitted plurality of modulation signals includes transmission data and one of the pilot symbol sequences.

Transmission apparatus, reception apparatus and digital radio communication method

A transmission apparatus and method include modulating a transmission signal using a first modulation scheme selected from a plurality of modulation schemes to generate a first symbol sequence. A second symbol, generated using a phase shift keying (PSK) modulation scheme, is inserted in the first symbol sequence to generate a first modulation signal for transmission. A second modulation signal is received that includes a third symbol generated using a PSK modulation scheme and inserted in a second symbol sequence generated using a second modulation scheme selected from the plurality of modulation schemes. The third symbol is extracted from the received modulation signal. A transmission path associated with the received modulation signal is estimated using the third symbol. A received data signal from the second symbol sequence included in the received modulation signal is output using the estimated transmission path.

COMMUNICATION APPARATUS AND COMMUNICATION METHOD

Modulated signal A is transmitted from a first antenna, and modulated signal B is transmitted from a second antenna. As modulated signal B, modulated symbols S2(i) and S2(i+1) obtained from different data are transmitted at time i and time i+1 respectively. In contrast, as modulated signal A, modulated symbols S1(i) and S1(i)′ obtained by changing the signal point arrangement of the same data are transmitted at time i and time i+1 respectively. As a result the reception quality can be changed intentionally at time i and time i+1, and therefore using the demodulation result of modulated signal A of a time when the reception quality is good enables both modulated signals A and B to be demodulated with good error rate performances.

Encoding method, encoder, and decoder

A low-density parity check convolution code (LDPC-CC) is made, and a signal sequence is sent after being subjected to an error-correcting encodement using the low-density parity check convolution code. In this case, a low-density parity check code of a time-variant period (3g) is created by linear operations of first to 3g-th (letter g designates a positive integer) parity check polynomials and input data.

Digital mobile wireless communications apparatus and the system using the same

A digital-mobile-wireless-communications apparatus and the system using the same evaluate a transmission environment of transmission paths. The communications apparatus calculates not only a Doppler frequency of carrier waves based on a velocity of the communications apparatus, but also a receiving-electric-field intensity based on a received radio wave. Furthermore, it has a capability of acquiring the transmission environment of the transmission paths by an evaluation based on the calculated two results, i.e., the Doppler frequency and the receiving-electric-field intensity, and data in a bit-error-rate (BER) vs. receiving-electric-field-intensity characteristics model using a carrier frequencies' shift (Doppler frequency) as a parameter.

Transmission and reception signal processor and method

A transmission apparatus includes a plurality of orthogonal frequency division multiplexing (OFDM) modulation signal generators, which generate a first OFDM modulation signal and a second OFDM modulation signal. The transmission apparatus also includes a transmitter that transmits the first OFDM modulation signal from a first antenna and the second OFDM modulation signal from a second antenna, in an identical frequency band. A reception apparatus is provided, which includes a plurality of antennas that receive a plurality of OFDM modulation signals; a plurality of OFDM demodulators that transform the plurality of OFDM modulation signals to a plurality of reception signals using Fourier transform; an estimator that outputs a distortion estimation signal using one or more symbols for demodulation included in the plurality of reception signals; and a demodulator that compensates for distortion of the reception signals using the distortion estimation signal and demodulates a data symbol included ...

TRANSMISSION METHOD AND TRANSMISSION APPARATUS

Of any one of transmission method X of transmitting modulated signal A and modulated signal B including the same data from a plurality of antennas and transmission method Y of transmitting modulated signal A and modulated signal B having different data from the plurality of antennas, base station apparatus 201 does not change the transmission method during data transmission and changes only the modulation scheme. Base station apparatus 201 transmits modulated signal A and modulated signal B to communication terminal apparatus 251 using the determined transmission method and modulation scheme. In this way, it is possible to improve data transmission efficiency when transmitting data using the plurality of antennas.

RECEPTION APPARATUS AND ASSOCIATED METHOD OF RECEIVING ENCODED DATA

A transmission apparatus includes an encoder that codes a data sequence with a parity check matrix, wherein the data sequence includes a final information bit sequence and virtual information bits, and outputs the final information bit sequence and a parity sequence, as LDPC codes, and a transmitter that transmits the LDPC codes as a transmission data. A column length of the parity check matrix is longer than a total length of the final information bit sequence and the parity sequence, by a length of the virtual information bits that are set to “0” and are not transmitted. The total length of the final information bit sequence and the parity sequence has a sequence length corresponding to a length from a first column to a predetermined column of the parity check matrix. The encoder generates the LDPC codes by using the first column to the predetermined column among one or more column(s) of the parity check matrix. The present invention relates to an encoder, decoder and encoding method using a low-density parity-check convolutional code (LDPC-CC) supporting a plurality of coding rates.In recent years, attention has been attracted to a low-density parity-check (LDPC) code as an error correction code that provides high error correction capability with a feasible circuit scale. Because of its high error correction capability and ease of implementation, an LDPC code has been adopted in an error correction coding scheme for IEEE802.11n high-speed wireless LAN systems, digital broadcasting systems, and so forth.An LDPC code is an error correction code defined by low-density parity check matrix H. An LDPC code is a block code having a block length equal to number of columns N of parity check matrix H (e.g. see Non-Patent Literature 1, Non-Patent Literature 4, or Non-Patent Literature 11). A random-like LDPC code, array LDPC code, and QC-LDPC code (QC: Quasi-Cyclic) are proposed in Non-Patent Literature 2, Non-Patent Literature 3, and Non-Patent Literature 12, for example. ...

RADIO BASE STATION DEVICE, RADIO TERMINAL DEVICE, AND RADIO COMMUNICATION SYSTEM

It is possible to provide a radio communication system, a radio base station device, and a radio terminal device capable of reducing the power consumption in a radio terminal device without thinning pilot signals used for measuring upstream line quality. In the radio base station device (100) used in a radio communication system using different frequency bands for the upstream line and the downstream line, an upstream line pilot generation unit (115) forms a CQI measuring pilot signal and an upstream line RF unit (105) transmits the communication quality measuring pilot signal by using the upstream line use frequency band in the upstream line pilot transmission section. Thus, the upstream communication quality measuring pilot signal used by the radio base station device (100) to measure the line quality is transmitted by using the upstream line frequency band and accordingly, it is possible to reduce the power consumption in the radio terminal device.

TRANSMISSION METHOD, TRANSMISSION APPARATUS, RECEPTION METHOD AND RECEPTION APPARATUS

A low-density parity check convolution code (LDPC-CC) is made, and a signal sequence is sent after being subjected to an error-correcting encodement using the low-density parity check convolution code. In this case, a low-density parity check code of a time-variant period (3g) is created by linear operations of first to 3g-th (letter g designates a positive integer) parity check polynomials and input data.

OUTPUT SIGNAL GENERATING METHOD, DECODED DATA GENERATING METHOD, OUTPUT SIGNAL GENERATING APPARATUS, AND DECODED DATA GENERATING APPARATUS

A transmitter apparatus wherein a simple structure is used to successfully suppress the degradation of error rate performance that otherwise would be caused by fading or the like. There are included encoding parts that encode transport data; a mapping part that performs such a mapping that encoded data sequentially formed by the encoding parts are not successively included in the same symbol, thereby forming data symbols; and a symbol interleaver that interleaves the data symbols. In this way, a low computational complexity can be used to perform an interleaving process equivalent to a bit interleaving process to effectively improve the reception quality at a receiving end. 1. An output signal generating method comprising:generating, by a processor, a plurality of encoded data sequences configured by a predetermined number of bits, by encoding transmit data configured by a plurality of bits;generating one symbol sequence by one modulating process, selected from a plurality of modulating processes, on the encoded data sequences; andoutputting one baseband signal sequence generated by using an OFDM scheme, for the one symbol sequence, wherein:the one modulating process generates the one symbol sequence configured by QPSK symbols generated by using a QPSK scheme or 16QAM symbols generated by using a 16QAM scheme;the one symbol sequence generated by using the QPSK scheme is configured with first two encoded data sequences in the plurality of encoded data sequences;the one symbol sequence generated by using the 16QAM scheme is configured with the first two encoded data sequences and second two encoded data sequences in the plurality of encoded data sequences;a number of the 16QAM symbols is the same as a number of the QPSK symbols in the one symbol sequence;specific two bits extracted from a plurality of bits configuring the QPSK symbols and the 16QAM symbols in the one symbol sequence are bits belonging to the first two encoded data sequences;a number of the encoded ...

Transmission device, reception device and radio communication method

On the transmitting side a spread modulated signal that has undergone spread spectrum processing and an information modulated signal that has not undergone spread spectrum processing are multiplexed in a same frequency band. On the receiving side the specific modulated signal is first demodulated by a spread spectrum demodulation section 1803, then a replica signal of the specific modulated signal is generated by a spread spectrum modulated signal regeneration section 1805, and the information signal that has not undergone spread spectrum processing is extracted by eliminating the replica signal from the multiplex signal. By this means, even when a large number of information signals are transmitted in a same frequency band, these signals can be separated and demodulated satisfactorily on the receiving side.

Base station, communication system including base station and transmission method

Channel fluctuation values on propagation paths of modulated signals transmitted from a plurality of antennas are estimated, an eigenvalue of a channel fluctuation matrix created with the above-mentioned channel fluctuation values as elements is found in order to relate antenna received signals to modulated signals, and using that eigenvalue, receiving antenna selection, combining of modulated signals, and weighting processing on soft decision decoded values, are performed, and modulated signals are demodulated. By this means, it is possible to perform demodulation processing based on the effective reception power of a modulated signal (that is to say, the essential reception power, of the reception power obtained by a receiving apparatus, that can be effectively used when demodulating a modulated signal), enabling the precision of demodulation of modulated signals to be improved.

Modulation method and radio communication system

An input digital signal is periodically and alternately subjected to first modulation and second modulation, being thereby converted into a pair of a baseband I signal and a baseband Q signal. The first modulation and the second modulation are different from each other. The pair of the baseband I signal and the baseband Q signal are outputted. The first modulation may be at least 8-signal-point modulation while the second modulation may be phase shift keying.

Modulator and modulation method

A transmitter apparatus wherein a relatively simple structure is used to suppress burst errors without changing the block sizes of encoded blocks even when the number of modulation multi-values is increased. An encoding part subjects transport data to a block encoding process to form block encoded data. A modulating part modulates the block encoded data to form data symbols; and an arranging (interleaving) part arranges (interleaves) the block encoded data in such a manner that the intra-block encoded data of the encoded blocks, which include their respective single different data symbol, get together, and then supplies the arranged (interleaved) block encoded data to the modulating part. In this way, there can be provided a transmitter apparatus wherein a relatively simple structure is used to suppress burst errors without changing the block sizes of encoded blocks even when the number of modulation multi-values is increased.

Transmission and reception apparatus and method

A transmission apparatus includes a plurality of orthogonal frequency division multiplexing (OFDM) modulation signal generators, which generate a first OFDM modulation signal and a second OFDM modulation signal. The transmission apparatus also includes a transmitter that transmits the first OFDM modulation signal from a first antenna and the second OFDM modulation signal from a second antenna, in an identical frequency band. A reception apparatus is provided, which includes a plurality of antennas that receive a plurality of OFDM modulation signals; a plurality of OFDM demodulators that transform the plurality of OFDM modulation signals to a plurality of reception signals using Fourier transform; an estimator that outputs a distortion estimation signal using one or more symbols for demodulation included in the plurality of reception signals; and a demodulator that compensates for distortion of the reception signals using the distortion estimation signal and demodulates a data symbol included in the reception signals.

RECEPTION METHOD AND RECEPTION APPARATUS

A radio transmitting apparatus that has a plurality of antennas and changes the number of modulated signals transmitted simultaneously according to the propagation environment and so forth. A transmission power changing section of a radio transmitting apparatus of the present invention adjusts the pilot symbol signal level so as to match the data symbol composite signal level according to the number of transmit modulated signals set by a modulated signal number setting section . By this means, the operating range of received pilot symbols and the operating range of received data symbols become approximately the same on the receiving side, enabling pilot symbol quantization error to be reduced. As a result, the precision of radio wave propagation environment estimation, time synchronization, and frequency offset estimation using pilot symbols improves, and consequently data reception quality improves. 1. A reception method comprising:receiving a plurality of modulated signals using a plurality of antennas, wherein:at least one modulated signal among the received plurality of modulated signals includes a frequency offset estimation signal, a channel fluctuation estimation signal, a first gain control signal, and a second gain control signal,the first gain control signal is arranged ahead of the frequency offset estimation signal, andthe second gain control signal is arranged subsequent to the frequency offset estimation signal and ahead of the channel fluctuation estimation signal;controlling a gain of the at least one modulated signal using the first gain control signal and the second gain control signal;correcting a frequency offset of the at least one modulated signal using the frequency offset estimation signal;estimating a channel fluctuation of the at least one modulated signal where the frequency offset is corrected, using the channel fluctuation estimation signal;separating the at least one modulated signal where the frequency offset is corrected, from the ...

Transmitting apparatus, transmission method, receiving apparatus, and receiving method

A transmitting apparatus and method transmits different modulated signals from a plurality of antennas, and employs a configuration that includes a modulation section that obtains a modulated signal by performing signal point mapping of transmit bits using a signal point arrangement that is divided into a plurality of signal point sets on the IQ plane, whereby the minimum distance between signal points within a signal point set is smaller than the minimum signal point distance between signal point sets; and an antenna that transmits a modulated signal obtained by the modulation section. A signal point generating apparatus generates a first and second symbols to be transmitted by first and second antennas, respectively.

DECODING METHOD AND DECODING APPARATUS

A decoding device allowing a high-speed decoding operation. In a decoding section (), if a degree of a check equation by a check matrix is D and the relationship between the check equation of the j+first row of the check matrix and the cheek equation of the jth row is shifted by n-bit, row processing operation sections ( to ) and column processing operation sections ( to ) perform the operation of a protograph in which the columns of the check matrix are delimited for each “(D+1)×N (N: natural number),” and the rows of the check matrix are delimited for each “(D+1)×N/n,” and formed as the processing unit of the row processing operation and column processing operation. 1. A decoding method that performs belief propagation decoding of a low density parity check convolutional code defined by a parity check matrix , comprising: the row process calculation updates log-likelihood ratios corresponding to each row of a parity check matrix, and', 'the column process calculation updates log-likelihood ratios corresponding to each column of the parity check matrix; and, 'a calculating step of performing calculation using a plurality of calculation systems in which a row process calculation and a column process calculation are combined, wherein'}an estimating step of estimating a codeword using a calculation result in the calculating step, wherein:the parity check matrix allocates regularly a protograph comprising a plurality of rows and a plurality of columns;elements of the parity check matrix except for a position where the protograph is allocated are zero; rows of the parity check matrix are divided by a number of rows of the protograph constituting the parity check matrix multiplied by N, N being a natural number,', 'columns of the parity check matrix are divided by a number of columns of the protograph multiplied by M, M being a natural number, and', 'a plurality of blocks made of the divided rows and columns are allocated to the plurality of groups; and, 'the calculating ...

TRANSMISSION APPARATUS, RECEPTION APPARATUS AND DIGITAL RADIO COMMUNICATION METHOD

A transmission method includes generating first symbols for transmitting data, a signal point of each of the first symbols on an in-phase and quadrature-phase plane comprising an in-phase component and a quadrature-phase component and generating a second symbol, the second symbol being a pilot symbol. The method further includes selecting an insertion pattern of the second symbol, from a plurality of predetermined insertion patterns, inserting the second symbol in the first symbols based on the selected insertion pattern to generate a transmission signal, and transmitting the transmission signal. The first symbols are generated using a modulation scheme selected from a plurality of modulation schemes. 1. A transmission method comprising:generating first symbols for transmitting data, a signal point of each of the first symbols on an in-phase and quadrature-phase plane comprising an in-phase component and a quadrature-phase component;generating a second symbol, the second symbol being a pilot symbol;selecting an insertion pattern of the second symbol, from a plurality of predetermined insertion patterns;inserting the second symbol in the first symbols based on the selected insertion pattern to generate a transmission signal; andtransmitting the transmission signal,wherein the first symbols are generated using a modulation scheme selected from a plurality of modulation schemes.2. The transmission method according to claim 1 , wherein the insertion pattern comprises an insertion interval of the second symbol in the first symbols.3. The transmission method according to claim 1 , wherein the modulation scheme used to generate the first symbol is selected from the plurality of modulation schemes based on a communication situation between a transmission apparatus and a reception apparatus.4. The transmission method according to claim 2 , wherein the insertion interval of the second symbol in the first symbols can be changed based on a communication situation between the ...

TRANSMISSION METHOD

A transmission method includes generating a plurality of orthogonal frequency division multiplexing (OFDM) signals, each signal including different data and some of the plurality of OFDM signals including pilot symbols. The pilot symbols are assigned to a predetermined subcarrier in predetermined time. At least one of the plurality of OFDM signals is assigned the pilot symbols to the predetermined subcarrier in the predetermined time, and other OFDM signals are assigned data to the predetermined subcarrier in the predetermined time. The method further includes converting each of the plurality of OFDM signals to a radio signal and transmitting each of the radio signals from a different antenna. 1. A transmission method comprising:generating a plurality of orthogonal frequency division multiplexing (OFDM) signals, each signal including different data;some of the plurality of OFDM signals include pilot symbols;the pilot symbols are assigned to a predetermined subcarrier in predetermined time;at least one of the plurality of OFDM signals is assigned the pilot symbols to the predetermined subcarrier in the predetermined time, and other OFDM signals are assigned data to the predetermined subcarrier in the predetermined time,converting each of the plurality of OFDM signals to a radio signal; andtransmitting each of the radio signals from a different antenna.2. The transmission method according to claim 1 , wherein the predetermined subcarriers in the predetermined time assigned the pilot symbols claim 1 , are different subcarriers in the predetermined time of the each OFDM signal.3. The transmission method according to claim 1 , wherein at least one of the plurality of the OFDM signals does not include pilot symbols in the predetermined time. This application is a continuation of pending U.S. patent application Ser. No. 13,433,577, filed on Mar. 29, 2012, which is a continuation of U.S. patent application Ser. No. 13/010,150, filed on Jan. 20, 2011 (Now U.S. Pat. No. 8,175 ...

TRANSMITTING METHOD, RECEIVING METHOD, RECEIVING APPARATUS AND TRANSMITTING APPARATUS

A transmitter apparatus wherein a simple structure is used to successfully suppress the degradation of error rate performance that otherwise would be caused by fading or the like. There are included encoding parts (-) that encode transport data; a mapping part () that performs such a mapping that encoded data sequentially formed by the encoding parts (-) are not successively included in the same symbol, thereby forming data symbols; and a symbol interleaver () that interleaves the data symbols. In this way, a low computational complexity can be used to perform an interleaving process equivalent to a bit interleaving process to effectively improve the reception quality at a receiving end. 1. A transmitting method comprising:generating encoded data configured by a plurality of bits by encoding transmit data configured by a plurality of bits;generating a baseband signal corresponding to a symbol by modulating the encoded data; andtransmitting a transmit signal based on the baseband signal, wherein:the encoded data being modulated by using QPSK or 16QAM, and whichever of the QPSK or the 16QAM is used, specific two bits extracted from a plurality of bits configuring the symbol are bits belonging to specific encoded data; andthe specific encoded data is LDPC encoded data.2. The transmitting method according to claim 1 , wherein at least one bit of the specific two bits is a most significant bit of a 16QAM symbol.3. The transmitting method according to claim 1 , wherein other two bits different from the specific two bits in the plurality of bits configuring a 16QAM symbol are bits belonging to other encoded data different from the specific encoded data.4. The transmitting method according to claim 1 , wherein the modulated signal is a signal formed using an OFDM method.5. A receiving method comprising:receiving a modulated signal;generating a baseband signal from the received modulated signal;generating encoded data configured by a plurality of bits in a symbol ...

WIRELESS COMMUNICATION METHOD AND TRANSMISSION APPARATUS

A wireless communication method for a transmission apparatus that transmits an OFDM (orthogonal frequency division multiplexing) signal using a communication band, which comprises a plurality of subcarrier groups each including a plurality of subcarriers. The method includes specifying which subcarrier group and how many subcarriers are to be used to transmit the OFDM signal, determining a configuration of a transmission frame, generating the OFDM signal by mapping data symbols according to the determined configuration of the transmission frame, and transmitting the generated OFDM signal. 1. A wireless communication method for a transmission apparatus that transmits an OFDM (orthogonal frequency division multiplexing) signal using a communication band which comprises a plurality of subcarrier groups each including a plurality of subcarriers , the method comprising:specifying which subcarrier group and how many subcarriers are to be used to transmit the OFDM signal and determining a configuration of a transmission frame;generating the OFDM signal by mapping data symbols according to the determined configuration of the transmission frame; andtransmitting the generated OFDM signal, wherein:a number of subcarriers to be used to transmit the OFDM signal is variable;the OFDM signal may be generated using a plurality of modulation schemes including QPSK and 16QAM;a plurality of mapping patterns are prepared for each of the plurality of modulation schemes, each mapping pattern indicating a combination of candidate positions of signal points on an IQ plane; andcombinations of candidate positions of signal points based on mapping patterns other than a first mapping pattern included in the plurality of mapping patterns are generated by rotating a first combination of candidate positions of signal points based on the first mapping pattern, in a same direction, around an origin on the IQ plane.2. The wireless communication method according to claim 1 , wherein:each of the ...

Wireless communication device and wireless communication method

A wireless communication device transmits and receives a signal by a wireless communication using a millimeter wave frequency band. The wireless communication device includes an antenna section having directivities in a plurality of different directions, an antenna control section adapted to form a directivity in a prescribed direction among the plurality of directivities of the antenna section, a direction and position estimation section adapted to estimate direction and position information of a wireless communication device to be communicated with, which is a target for the wireless communication, in accordance with a receiving signal received by the antenna section having the directivity formed, and a display section adapted to display the estimated direction and position information of the wireless communication device to be communicated with.

RECEIVING APPARATUS AND RECEIVING METHOD

A multiple-input and multiple-output (MIMO) transmission apparatus includes a modulation signal generating section and a MIMO transmitting section. The modulation signal generating section generates: (i) a first OFDM modulation signal, in which a plurality of subcarriers include a subcarrier carrying a pilot symbol and a subcarrier carrying a data symbol, in both a first time period and a second time period; and (ii) a second OFDM modulation signal, in which the plurality of subcarriers include a subcarrier carrying a pilot symbol and a subcarrier carrying a data symbol in the first time period, while in the second time period an in-phase component and a quadrature-phase component of every subcarrier included in the plurality of subcarriers are zero. The MIMO transmitting section transmits the first OFDM modulation signal from a first antenna and transmits the second OFDM modulation signal from a second antenna. 1. A receiving apparatus comprising: (i) a first OFDM modulation signal, in which a plurality of subcarriers include, at a first time, a subcarrier carrying a symbol including multiplex information, and include, at a second time, a subcarrier carrying a pilot symbol and a subcarrier carrying a data symbol, in both a first time period and a second time period; and', '(ii) a second OFDM modulation signal, in which the plurality of subcarriers include, at the first time, a subcarrier carrying a symbol including multiplex information, and include, at the second time, a subcarrier carrying the pilot symbol and a subcarrier carrying the data symbol in the first time period, while in the second time period, an in-phase component and a quadrature-phase component of every subcarrier included in the plurality of subcarriers are zero; and, '(a) a receiving section that receives, using a plurality of antennas, spatially multiplexed signal of(b) a decoding section that determines a number of spatial multiplexing in the first time period and the second time period using ...

RECEPTION METHOD AND RECEPTION APPARATUS

A radio transmitting apparatus that has a plurality of antennas and changes the number of modulated signals transmitted simultaneously according to the propagation environment and so forth. A transmission power changing section of a radio transmitting apparatus of the present invention adjusts the pilot symbol signal level so as to match the data symbol composite signal level according to the number of transmit modulated signals set by a modulated signal number setting section . By this means, the operating range of received pilot symbols and the operating range of received data symbols become approximately the same on the receiving side, enabling pilot symbol quantization error to be reduced. As a result, the precision of radio wave propagation environment estimation, time synchronization, and frequency offset estimation using pilot symbols improves, and consequently data reception quality improves. 118-. (canceled)19. A wireless communications method comprising:receiving a plurality of modulated signals from at least one antenna, with at least one modulated signal from among the plurality thereof including, in a predetermined order, a frequency offset estimation signal, a channel fluctuation estimation signal, a first gain control signal, and a second gain control signal;controlling a gain of the at least one modulated signal based upon the first and second gain control signals;adjusting a frequency offset of the at least one modulated signal based upon the frequency offset estimation signal;estimating a channel fluctuation of the at least one modulated signal where the frequency offset is adjusted, based upon the channel fluctuation estimation signal;separating the at least one modulated signal from the received plurality of modulated signals where the frequency offset is adjusted based upon the estimated channel fluctuation; anddemodulating the separated at least one modulated signal.20. The wireless communications method according to wherein the predetermined ...

TRANSMISSION DEVICE, RECEPTION DEVICE, AND RADIO COMMUNICATION METHOD

A transmitting apparatus includes an OFDM modulator that generates a first modulation symbol by modulating a first information signal using a first modulation scheme, a signal point of the first modulated information signal being at a first position in an in-phase quadrature-phase plane. A second modulation symbol by modulating a second information signal using the first modulation scheme, and by changing a second position at which a signal point of the modulated second information signal is arranged to a third position in the in-phase quadrature-phase plane, and an OFDM modulation signal including the first modulation symbol and the second modulation symbol, wherein the OFDM modulation signal comprises a plurality of subcarriers. 18-. (canceled)9. A communications apparatus comprising:a first spreading section configured to generate a first spread signal by spreading using a first spreading code that has a first spectrum spreading ratio;a second spreading section configured to generate a second spread spectrum signal by spreading using a second spreading code that has a second spreading ratio different from the first spreading ratio; anda multiplexing section configured to generate a multiplex signal by multiplexing the first and second spread spectrum signals in a same frequency band.10. The communications apparatus according to further comprising a transmission section configured to wirelessly transmit the multiplex signal.11. The communications apparatus according to wherein said transmission section is configured to transmit one of the first and second spread spectrum signals at a greater transmission power than the other.12. The communications apparatus according to wherein the first spreading ratio is larger than the second spreading ratio; and wherein said transmission section is configured to transmit the first spread spectrum signal at a greater transmission power than the second spread spectrum signal.13. The communications apparatus according to wherein ...

METHOD FOR DIGITAL WIRELESS COMMUNICATIONS

In a multivalue modulation type with one pilot symbol inserted for every 3 or more symbols, signal points of each one symbol immediately before and after a pilot symbol are modulated using a modulation type different from that for pilot symbols. In this way, it is possible to suppress deterioration of the accuracy in estimating the reference phase and amount of frequency offset by pilot symbols and improve the bit error rate characteristic in the signal to noise ratio in quasi-coherent detection with symbols whose symbol synchronization is not completely established. 120-. (canceled)21. A wireless communications apparatus comprising: a first modulator configured to modulate a first pilot symbol according to a first modulation scheme,', 'a second modulator configured to modulate specific first symbols according to a second modulation scheme different from the first modulation scheme, and', 'a timing controller cooperating with said first and second modulators so that modulated specific first symbols are inserted before and after associated modulated first pilot symbols; and, 'a transmitter comprising'}a receiver configured to generate a reception baseband signal based upon modulated second pilot symbols with modulated specific second symbols inserted before and after associated modulated second pilot symbols.22. The wireless communications apparatus according to wherein said timing controller is configured so that the modulated specific first symbols are inserted immediately before and after the associated modulated first pilot symbols.23. The wireless communications apparatus according to wherein said receiver is configured to generate the reception baseband signal based upon modulated second pilot symbols with modulated specific second symbols inserted immediately before and after the associated modulated second pilot symbols.24. The wireless communications apparatus according to wherein said first and second modulation schemes each comprises a multivalue ...

Encoder, decoder, transmitting apparatus, and receiving apparatus

There is provided an encoder that provides a termination sequence with a simple structure for LDPC-CC encoding and reduces an amount of the termination sequence transmitted to a transmission line. The LDPC-CC encoder connects a first encoder to a second encoder to perform encoding and thereby carry out LDPC-CC encoding, the first encoder performing encoding based on an partial parity check matrix for information bits obtained by extracting a sequence corresponding to the information bits in a parity check matrix and the second encoder performing encoding based on a partial parity check matrix for parity bits obtained by extracting a sequence corresponding to the parity bits in the parity check matrix. A termination sequence generator generates a termination sequence including the same number of bits as the memory length of the first encoder and provides the generated termination sequence as an input sequence.

TRANSMITTING APPARATUS, RECEIVING APPARATUS, TRANSMISSION METHOD, AND RECEPTION METHOD

In a communication system in which propagation path error tolerance is improved by switching the modulation method or error correction method adaptively according to the state of the propagation path, signals MX, MY, CX, and CY indicating the modulation method and error correction method used by the transmitting side are transmitted arranged at discrete locations within the same frame. By this means, the possibility of discretely arranged signals MX and MY, or CX and CY, both degrading is made low even if the transmit signal experiences fading or propagation path fluctuations. As a result, it is possible for the modulation method information signal and/or error correction method information signal to be restored correctly on the receiving side. 1. A transmission method comprising:generating a control information relating to a data signal;forming a transmission frame by repeating and discretely arranging the same control information at locations separated by a predetermined time in a direction of time axis; andtransmitting the data signal and the control information using the transmission frame.2. The transmission method according to claim 1 , wherein the predetermined time is a reciprocal of a maximum Doppler frequency.3. The transmission method according to claim 1 , wherein the control information is modulated using QPSK or BPSK modulation.4. The transmission method according to claim 1 , wherein the control information includes error correction method information relating to the data signal.5. The transmission method according to claim 1 , wherein the control information includes modulation method information relating to the data signal.6. A transmission apparatus comprising:a control information signal generator that generates a control information relating to a data signal;a frame former that forms a transmission frame by repeating and discretely arranging the same control information at locations separated by a predetermined time in a direction of time axis; ...

TRANSMITTING APPARATUS, TRANSMITTING METHOD, RECEIVING APPARATUS AND RECEIVING METHOD

Modulated signal A is transmitted from a first antenna, and modulated signal B is transmitted from a second antenna. As modulated signal B, modulated symbols S2(i) and S2(i+1) obtained from different data are transmitted at time i and time i+1 respectively. In contrast, as modulated signal A, modulated symbols S1(i) and S1(i)′ obtained by changing the signal point arrangement of the same data are transmitted at time i and time i+1 respectively. As a result the reception quality can be changed intentionally at time i and time i+1, and therefore using the demodulation result of modulated signal A of a time when the reception quality is good enables both modulated signals A and B to be demodulated with good error rate performances. 1. A transmitting apparatus comprising:a signal processing section that generates a first modulated symbol sequence and a second modulated symbol sequence, the first modulated symbol sequence obtained by sequentially mapping a set of bits included in a first transmit data to signal points in an I-Q plane using a first mapping pattern that is based on a predetermined modulation method, the second modulated symbol sequence obtained by sequentially mapping a set of bits included in a second transmit data to signal points in the I-Q plane using a second mapping pattern that is based on the predetermined modulation method; anda plurality of antennas that transmit the first modulated symbol sequence and the second modulated symbol sequence in a same frequency and at a same time,wherein:the first mapping pattern is a mapping pattern changed in amplitude from a third mapping pattern, the third mapping pattern depending on the predetermined modulation method;the second mapping pattern is a mapping pattern changed in amplitude from the third mapping pattern and having a phase that is changed from a phase of the third mapping pattern toward a predetermined direction; andsignal points obtained by mapping a predetermined set of bits in the I-Q plane ...

TRANSMISSION APPARATUS AND RECEPTION APPARATUS

A transmitter apparatus wherein a relatively simple structure is used to suppress burst errors without changing the block sizes of encoded blocks even when the number of modulation multi-values is increased. An encoding part subjects transport data to a block encoding process to form block encoded data. A modulating part modulates the block encoded data to form data symbols; and an arranging (interleaving) part arranges(interleaves) the block encoded data in such a manner that the intra-block encoded data of the encoded blocks, which include their respective single different data symbol, get together, and then supplies the arranged(interleaved) block encoded data to the modulating part. In this way, there can be provided a transmitter apparatus wherein a relatively simple structure is used to suppress burst errors without changing the block sizes of encoded blocks even when the number of modulation multi-values is increased. 1. A transmission apparatus comprising:an encoding section that performs error correction encoding processing on transmit data comprising a plurality of bits to form a plurality of error correction encoding data each comprising a plurality of bits;a modulation section that modulates the plurality of error correction encoding data using a QPSK modulation scheme or a 16QAM modulation scheme to generate a modulation symbol; anda transmission section that transmits the modulation symbol, wherein:the modulation section generates the modulation symbol, using a first error correction encoding data for the QPSK modulation scheme, and, using the first error correction encoding data and a second error correction encoding data for the 16QAM modulation scheme, at a first time slot.2. The transmission apparatus according to claim 1 , wherein the modulation section generates 2 bits forming the modulation symbol claim 1 , using the first error correction encoding data claim 1 , and generates another 2 bits forming the rest of the modulation symbol claim 1 , ...

TRANSMISSION METHOD, TRANSMISSION APPARATUS AND RECEPTION APPARATUS

A method of generating modulation signals is disclosed including generally three steps. A plurality of modulation signals are generated, each of which is to be transmitted from a different one of a plurality of antennas in an identical frequency band, wherein each modulation signal includes a pilot symbol sequence including a plurality of pilot symbols used for demodulation. Each of the pilot symbol sequences is inserted at the same temporal point in each modulation signal, wherein the pilot symbol sequences are orthogonal to each other with zero mutual correlation among the plurality of modulation signals, each pilot symbol having a non-zero amplitude, the quantity of the plurality of pilot symbols in each sequence being greater than the quantity of the plurality of modulation signals to be transmitted. The plurality of modulation signals each including different transmission data and one of the pilot symbol sequences are output to the antennas. 1. A method of generating modulation signals , the method comprising:generating a plurality of modulation signals each of which is to be transmitted from a different one of a plurality of antennas in an identical frequency band, wherein each modulation signal includes a pilot symbol sequence comprising a plurality of pilot symbols used for demodulation;inserting each of the pilot symbol sequences at the same temporal point in each modulation signal, wherein the pilot symbol sequences are orthogonal to each other with zero mutual correlation among the plurality of modulation signals, each pilot symbol having a non-zero amplitude, the quantity of the plurality of pilot symbols in each sequence being greater than the quantity of the plurality of modulation signals to be transmitted; andoutputting the plurality of modulation signals, each comprising different transmission data and one of the pilot symbol sequences, to the plurality of antennas.2. The method of claim 1 , wherein the plurality of pilot symbols used for ...

CONVOLUTIONAL CODE ENCODING METHOD

An encoder and decoder using LDPC-CC (Low Density Parity Check-Convolutional Codes) is disclosed. In the encoder (), an encoding rate setting unit () sets an encoding rate (s−1)/s (s=z), and an information creating unit () sets information including from information Xs,i to information Xz−1,i to zero. A first information computing unit (-) receives information X1,i at time point i to compute the X1(D) term of formula (1). A second information computing unit (-) receives information X2,i at time point i to compute the X2(D) term of formula (1). A third information computing unit (-) receives information X3,i at time point i to compute the X3(D) term of formula (1). A parity computing unit () receives parity Pi−1 at time point i−1 to compute the P(D) of formula (1). The exclusive OR of the results of the computation is obtained as parity Pi at time i. Ax. 2. The transmission apparatus according to claim 1 , wherein the time varying period of g is 3.3. The transmission apparatus according to claim 2 , wherein:{'sub': 'k', 'claim-text': {'br': None, 'i': B', 'D', 'D', '+D, 'sub': 'k', 'sup': b1', 'b2, '()=+1\u2003\u2003(Equation 3)'}, 'B(D) in the parity check polynomial of equation 1 and the parity check polynomial of equation 2 is represented as equation 3,'}where (b1 mod 3, b2 mod 3) is equal to (1, 2) or (2, 1); and {'br': None, 'i': A', 'D', 'D', '+D, 'sub': 'Xr,k', 'sup': ar,k,1', 'ar,k,2, '()=+1\u2003\u2003(Equation 4)'}, 'Ak(D) in the parity check polynomial of equation 1 and the parity check polynomial of equation 2 is represented as equation 4,'}where {(ar, k, 1) mod 3, (ar, k, 2) mod 3} is equal to (1, 2) or (2, 1).5. The reception apparatus according to claim 4 , wherein the time varying period of g is 3.6. The reception apparatus according to claim 5 , wherein:{'sub': 'k', 'claim-text': {'br': None, 'i': B', 'D', 'D', '+D, 'sub': 'k', 'sup': b1', 'b2, '()=+1\u2003\u2003(Equation 3)'}, 'B(D) in the parity check polynomial of equation 1 and the parity check ...

Receiving apparatus and receiving method

A transmitting apparatus and method transmits different modulated signals from a plurality of antennas, and employs a configuration that includes a modulation section that obtains a modulated signal by performing signal point mapping of transmit bits using a signal point arrangement that is divided into a plurality of signal point sets on the IQ plane, whereby the minimum distance between signal points within a signal point set is smaller than the minimum signal point distance between signal point sets; and an antenna that transmits a modulated signal obtained by the modulation section. A signal point generating apparatus generates a first and second symbols to be transmitted by first and second antennas, respectively.

Transmitting apparatus, receiving apparatus, transmission method, and reception method

A transmission frame generating device generates a transmission frame. The generating device includes a control information signal generator which generates a modulation method control signal indicating a modulation method used for a data signal and an error correction method control signal indicating an error correction method used for the data signal and a frame former which forms the transmission frame by arranging a training signal, the data signal, the modulation method control signal and the error correction method control signal on a plurality of subcarriers on a frequency axis. The modulation method control signal being repeatedly and discretely arranged on a first multiple of the plurality of subcarriers on the frequency axis and the error correction method control signal being repeatedly and discretely arranged on a second multiple of the plurality of the subcarriers on the frequency axis.

OFDM FRAME COMMUNICATION METHOD AND APPARATUS

A first radio signal is received that was transmitted from a first antenna at a transmitter and a second radio signal transmitted from a second antenna at the transmitter different from the first antenna. The first radio signal is converted to a first orthogonal frequency division multiplexing (OFDM) frame signal, and the second radio signal is converted to a second OFDM frame signal. The first OFDM frame signal includes a grid of multiple frequency subcarriers and time periods, each time period with the frequency carriers corresponding to a first OFDM symbol such that the first OFDM frame includes first OFDM symbols. A first OFDM symbol is carried on frequency subcarriers during a time period, and the first OFDM frame includes first reference OFDM symbols located at corresponding time-frequency resource elements in the grid. Each resource element is defined by a one of the frequency subcarriers and one of the time periods. The second OFDM frame signal is similar and includes second reference OFDM symbols sharing the same grid of frequency subcarriers and time periods as the first OFDM frame. But the second reference OFDM symbols are located at corresponding time-frequency resource elements in the grid different than the corresponding time-frequency resource elements to which the first reference OFDM signals are located their respective OFDM frame signals. The first and second reference OFDM symbols are used to demodulate the first and second OFDM frame signals. 1. A reception method comprising:receiving a first radio signal transmitted from a first antenna at a transmitter and a second radio signal transmitted from a second antenna at the transmitter different from the first antenna,converting the first radio signal to a first orthogonal frequency division multiplexing (OFDM) frame signal and the second radio signal to a second OFDM frame signal,wherein the first OFDM frame signal includes a grid of multiple frequency subcarriers and multiple time periods, each ...

TRANSMISSION APPARATUS AND ASSOCIATED METHOD OF ENCODING TRANSMISSION DATA

An encoder and decoder using LDPC-CC (Low Density Parity Check—Convolutional Codes) is disclosed. In the encoder (), an encoding rate setting unit () sets an encoding rate (s−1)/s (s=z), and an information creating unit () sets information including from information Xs,i to information Xz-1,i to zero. A first information computing unit (-) receives information X1,i at time point i to compute the X1(D) term of formula (1). A second information computing unit (-) receives information X2,i at time point i to compute the X2(D) term of formula (1). A third information computing unit (-) receives information X3,i at time point i to compute the X3(D) term of formula (1). A parity computing unit () receives parity Pi−1 at time point i−1 to compute the P(D) of formula (1). The exclusive OR of the results of the computation is obtained as parity Pi at time i. Ax. 1. A transmission apparatus comprising:an encoder that generates parity sequences by coding an information data sequence with a parity check matrix and to output the information data sequence and the parity sequences as low-density parity-check (LDPC) codes; anda transmitter that transmits the LDPC codes as a transmission data; “n” number of (where n is an integer equal to or greater than 1) parity check equation groups including a plurality of parity check polynomials are arranged in the parity check matrix,', 'each of the parity check polynomials satisfies zero,', 'the information data sequence has a sequence length corresponding to a length from a first column to a predetermined column of the parity check matrix, and', 'the encoder generates the LDPC codes by using the first column to the predetermined column among one or more column(s) of the parity check matrix., 'wherein'}3. A transmission method comprising:generating parity sequences by coding an information data sequence with a parity check matrix; andtransmitting low-density parity-check (LDPC) codes including the information data sequence and the parity ...

WIRELESS COMMUNICATION APPARATUS AND WIRELESS COMMUNICATION METHOD

A communication method of a base station transmits a modulation signal based on an OFDM (orthogonal frequency division multiplexing) modulation scheme to a plurality of communication terminals. The method includes forming a transmission frame on which a first subcarrier group and a second subcarrier group are arranged, and determining on a per frame basis, which subcarrier group of the first subcarrier group and the second subcarrier group is allocated to each of the plurality of communication terminals and what number of subcarriers are selected from the subcarrier group that is allocated to each of the plurality of communication terminals. The method further includes forming the transmission frame based on the determined subcarrier group and the determined number of subcarriers, transmitting the modulation signal including the transmission frame, and receiving feedback information including radio propagation condition estimation information from each of the plurality of communication terminals. 1. A communication method of a base station which transmits a modulation signal based on an OFDM (orthogonal frequency division multiplexing) modulation scheme to a plurality of communication terminals , the method comprising:forming a transmission frame on which a first subcarrier group and a second subcarrier group are arranged, the first subcarrier group on which a signal having a first transmission scheme is arranged and the second subcarrier group on which a signal having a second transmission scheme different from the signal having the first transmission scheme in transmission quality is arranged;determining on a per frame basis, which subcarrier group of the first subcarrier group and the second subcarrier group is allocated to each of the plurality of communication terminals and what number of subcarriers are selected from the subcarrier group that is allocated to said each of the plurality of communication terminals;forming the transmission frame based on the ...

TRANSMITTING APPARATUS, RECEIVING APPARATUS, TRANSMISSION METHOD, AND RECEPTION METHOD

A transmission frame generating device includes a control information signal generator and a frame former. The control information signal generator generates a modulation method information signal indicating a modulation method of a data signal and an error correction method information signal indicating an error correction method of the data signal. The frame former forms the transmission frame by repeating and discretely arranging the same modulation method information signal on a first multiple of a plurality of subcarriers on a frequency axis and by repeating and discretely arranging the same error correction method information signal on a second multiple of the plurality of the subcarriers on the frequency axis. 1. A transmission frame generating device for generating a transmission frame , comprising:a control information signal generator that generates a modulation method information signal indicating a modulation method of a data signal and an error correction method information signal indicating an error correction method of the data signal; anda frame former that forms the transmission frame by repeating and discretely arranging the same modulation method information signal on a first multiple of a plurality of subcarriers on a frequency axis and by repeating and discretely arranging the same error correction method information signal on a second multiple of the plurality of the subcarriers on the frequency axis.2. The transmission frame generating device according to claim 1 ,wherein the frame former forms the transmission frame by repeating and discretely arranging the same modulation method information signal on the first multiple of the plurality of subcarriers at the same first time and the same error correction method information signal on the second multiple of the plurality of the subcarriers at the same second time.3. The transmission frame generating device according to claim 1 ,wherein the frame former forms the transmission frame in which the ...

TRANSMISSION SIGNAL GENERATION APPARATUS, TRANSMISSION SIGNAL GENERATION METHOD, RECEPTION SIGNAL GENERATION APPARATUS, AND RECEPTION SIGNAL GENERATION METHOD

MIMO-OFDM communication is provided which allows high accuracy estimation of frequency offset, high accuracy estimation of a transmission path fluctuation and high accuracy synchronization/signal detection. Pilot symbol mapping is provided for forming pilot carriers by assigning orthogonal sequences to corresponding subcarriers among OFDM signals which are transmitted at the same time from respective antennas in the time domain. Even when pilot symbols are multiplexed among a plurality of channels (antennas), this allows frequency offset/phase noise to be estimated with high accuracy. 1. A transmission signal generation apparatus comprising:a mapper that generates a transmission signal using either a first transmission signal generation method of generating a first transmission signal including a first pilot symbol sequence and a second pilot symbol sequence, and a second transmission signal including a third pilot symbol sequence and a fourth pilot symbol sequence, or a second transmission signal generation method of generating a third transmission signal including a fifth pilot symbol sequence and a sixth pilot symbol sequence; andan Inverse Fourier transformer that generates a first OFDM signal by performing Inverse Fourier transform for the first transmission signal for transmitting the first OFDM signal from a first antenna, and generates a second OFDM signal by performing Inverse Fourier transform for the second transmission signal for transmitting the second OFDM signal from a second antenna in a same frequency and a same transmission period as the first OFDM signal by the first transmission signal generation method, or generates a third OFDM signal by performing Inverse Fourier transform for the third transmission signal for transmitting the third OFDM signal from the first antenna by the second transmission signal generation method,wherein: the first pilot symbol sequence in a first pilot carrier during a first time period;', 'the second pilot symbol ...

TRANSMISSION AND RECEPTION SIGNAL PROCESSOR AND METHOD

A transmission apparatus includes a plurality of orthogonal frequency division multiplexing (OFDM) modulation signal generators, which generate a first OFDM modulation signal and a second OFDM modulation signal. The transmission apparatus also includes a transmitter that transmits the first OFDM modulation signal from a first antenna and the second OFDM modulation signal from a second antenna, in an identical frequency band. A reception apparatus is provided, which includes a plurality of antennas that receive a plurality of OFDM modulation signals; a plurality of OFDM demodulators that transform the plurality of OFDM modulation signals to a plurality of reception signals using Fourier transform; an estimator that outputs a distortion estimation signal using one or more symbols for demodulation included in the plurality of reception signals; and a demodulator that compensates for distortion of the reception signals using the distortion estimation signal and demodulates a data symbol included in the reception signals. 1. A transmission apparatus comprising:circuitry, which, in operation, maps reference signals in first subcarriers at a first time and in second sub-carriers at a second time for first Orthogonal Frequency Division Multiplexing (OFDM) signals, wherein no signal is mapped in the second sub-carriers at the first time and in the first sub-carriers at the second time for the first OFDM signals, andwhich, in operation, maps reference signals in the second sub-carriers at the first time and in the first sub-carriers at the second time for second OFDM signals, wherein no signal is mapped in the first sub-carriers at the first time and in the second sub-carriers at the second time for the second OFDM signals; anda transmitter, which is coupled to the circuitry and which, in operation, transmits the first OFDM signals and the second OFDM signals from different antennas.2. The transmission apparatus according to claim 1 , wherein data is mapped to third sub- ...

RECEIVING APPARATUS AND RECEIVING METHOD

A receiver receives, using a plurality of antennas, a multiplexed signal that includes (i) a first OFDM modulation signal with a subcarrier carrying a symbol including multiplex information and a subcarrier carrying a pilot symbol and a subcarrier carrying a data symbol and (ii) a second OFDM modulation signal with a subcarrier carrying a symbol including multiplex information and a subcarrier carrying the pilot symbol and a subcarrier carrying the data symbol. A decoder uses the symbol including multiplex information and decodes the data symbol. 1. A radio transmission apparatus for a radio station , comprising:a first modulation signal generator;a second modulation signal generator;control circuitry configured to generate information indicating at least two different multiplexed modulation streams are to be transmitted in a same frequency band at the same time via first and second antennas, respectively; andwherein the first and second modulation signal generators are configured, based on the generated information, to respectively generate a first Orthogonal Frequency Division Multiplexed (OFDM) modulation signal and a second OFDM modulation signal which include different information from each other for transmission in the same frequency band at the same time via first and second antennas, respectively,wherein the first and second OFDM modulation signals each contains information indicating a number of modulation signals multiplexed and transmitted in the same frequency band at the same time, the number being at least two.2. The radio transmission apparatus in claim 1 , further comprising:a first transmitter including the first modulation signal generator, a first radio unit, and the first antenna, anda second transmitter including the second modulation signal generator, a second radio unit, and the second antenna.3. The radio transmission apparatus in claim 1 , wherein the control circuitry includes a frame signal generator.4. The radio transmission apparatus in ...

Transmission signal generation apparatus, transmission signal generation method, reception signal apparatus, and reception signal method

A transmission apparatus maps a first stream of input data to first complex symbols in serial format and convert them into first complex symbols in parallel format. They are inverse Fourier transformed into OFDM signals associated with multiple subcarriers that are transmitted via a first antenna over the multiple subcarriers in a same frequency band over a same time period that includes a same set of time slots. First pilot information is transmitted via a first antenna on a first one of a plurality of pilot subcarriers during the same set of time slots, and second pilot information is sent via a first antenna on a second one of a plurality of pilot subcarriers during the same set of time slots. The second pilot information is different from the first pilot information. A second stream of input data is similarly transformed to form second OFDM signals transmit via a second antenna over the multiple subcarriers in the same frequency band over the same time period that includes the same set of time slots. The first pilot information is transmitted via the second antenna on the second pilot subcarrier during the set of same time slots, and the second pilot information is transmitted on one of the pilot subcarriers during the same set of time slots.

TRANSMISSION APPARATUS, RECEPTION APPARATUS AND DIGITAL RADIO COMMUNICATION METHOD

A transmission apparatus and method include modulating a transmission signal using a first modulation scheme selected from a plurality of modulation schemes to generate a first symbol sequence. A second symbol, generated using a phase shift keying (PSK) modulation scheme, is inserted in the first symbol sequence to generate a first modulation signal for transmission. A second modulation signal is received that includes a third symbol generated using a PSK modulation scheme and inserted in a second symbol sequence generated using a second modulation scheme selected from the plurality of modulation schemes. The third symbol is extracted from the received modulation signal. A transmission path associated with the received modulation signal is estimated using the third symbol. A received data signal from the second symbol sequence included in the received modulation signal is output using the estimated transmission path. 1. Radio communications apparatus comprising a transceiver configured to:modulate a transmission signal using a first modulation scheme selected from a plurality of modulation schemes to generate a first symbol sequence;insert a second symbol, generated using a phase shift keying (PSK) modulation scheme, in the first symbol sequence to generate a first modulation signal for transmission;receive a second modulation signal that includes a third symbol generated using a PSK modulation scheme and inserted in a second symbol sequence generated using a second modulation scheme selected from the plurality of modulation schemes;extract the third symbol from the received modulation signal;estimate a transmission path associated with the received modulation signal using the third symbol; andoutput a received data signal from the second symbol sequence included in the received modulation signal using the estimated transmission path.2. The radio communications apparatus according to claim 1 , wherein the plurality of modulation schemes include M-ary modulation ...

TRANSMISSION AND RECEPTION APPARATUS AND METHOD

A transmission apparatus includes a plurality of orthogonal frequency division multiplexing (OFDM) modulation signal generators, which generate a first OFDM modulation signal and a second OFDM modulation signal. The transmission apparatus also includes a transmitter that transmits the first OFDM modulation signal from a first antenna and the second OFDM modulation signal from a second antenna, in an identical frequency band. A reception apparatus is provided, which includes a plurality of antennas that receive a plurality of OFDM modulation signals; a plurality of OFDM demodulators that transform the plurality of OFDM modulation signals to a plurality of reception signals using Fourier transform; an estimator that outputs a distortion estimation signal using one or more symbols for demodulation included in the plurality of reception signals; and a demodulator that compensates for distortion of the reception signals using the distortion estimation signal and demodulates a data symbol included in the reception signals. 1. A transmission apparatus comprising: [ inserting a first symbol for demodulation in a first plurality of subcarriers at a first time and in a second plurality of sub-carriers at a second time;', 'inserting a symbol, having both an in-phase (I) component and a quadrature-phase (Q) component in an I-Q plane of zero, in the second plurality of sub-carriers at the first time and in the first plurality of sub-carriers at the second time; and', 'inserting a first data symbol in the first and second pluralities of subcarriers at a third time; and, '(i) generate a first OFDM modulation signal by, inserting a symbol, having both an in-phase (I) component and a quadrature-phase (Q) component in the I-Q plane of zero, in the first plurality of subcarriers at the first time and in the second plurality of sub-carriers at the second time; and', 'inserting a second symbol for demodulation in the second plurality of sub-carriers at the first time and in the first ...

Transmission method and transmission apparatus

A transmission apparatus includes a plurality of antennas and a transmission scheme determination processor that selects one of either a first transmission scheme of transmitting a plurality of signals including a first amount of data in a frame, respectively, from the plurality of antennas, and a second transmission scheme of transmitting a plurality of signals including a second greater amount of data in a frame, respectively, from the plurality of antennas. The apparatus includes a modulation scheme selection processor that selects a modulation scheme among a plurality of modulation schemes and a control processor that controls the transmission scheme determination processor and the modulation scheme selection processor to change the transmission scheme less frequently than the modulation scheme. A transmitter transmits from the plurality of antennas a signal generated based on the selected transmission scheme and the selected modulation scheme.

TRANSMISSION APPARATUS AND ASSOCIATED METHOD OF ENCODING TRANSMISSION DATA

A transmission apparatus includes an encoder that codes a data sequence with a parity check matrix, wherein the data sequence includes a final information bit sequence and virtual information bits, and outputs the final information bit sequence and a parity sequence, as LDPC codes, and a transmitter that transmits the LDPC codes as a transmission data. A column length of the parity check matrix is longer than a total length of the final information bit sequence and the parity sequence, by a length of the virtual information bits that are set to “0” and are not transmitted. The total length of the final information bit sequence and the parity sequence has a sequence length corresponding to a length from a first column to a determined column of the parity check matrix. The encoder generates the LDPC codes by using the first column to the determined column among one or more column(s) of the parity check matrix. The present invention relates to an encoder, decoder and encoding method using a low-density parity-check convolutional code (LDPC-CC) supporting a plurality of coding rates.In recent years, attention has been attracted to a low-density parity-check (LDPC) code as an error correction code that provides high error correction capability with a feasible circuit scale. Because of its high error correction capability and ease of implementation, an LDPC code has been adopted in an error correction coding scheme for IEEE802.11n high-speed wireless LAN systems, digital broadcasting systems, and so forth.An LDPC code is an error correction code defined by low-density parity check matrix H. An LDPC code is a block code having a block length equal to number of columns N of parity check matrix H (e.g. see Non-Patent Literature 1, Non-Patent Literature 4, or Non-Patent Literature 11). A random-like LDPC code, array LDPC code, and QC-LDPC code (QC: Quasi-Cyclic) are proposed in Non-Patent Literature 2, Non-Patent Literature 3, and Non-Patent Literature 12, for example.However ...

COMMUNICATION APPARATUS AND COMMUNICATION METHOD

Modulated signal A is transmitted from a first antenna, and modulated signal B is transmitted from a second antenna. As modulated signal B, modulated symbols S2(i) and S2(i+1) obtained from different data are transmitted at time i and time i+1 respectively. In contrast, as modulated signal A, modulated symbols S1(i) and S1(i)′ obtained by changing the signal point arrangement of the same data are transmitted at time i and time i+1 respectively. As a result the reception quality can be changed intentionally at time i and time i+1, and therefore using the demodulation result of modulated signal A of a time when the reception quality is good enables both modulated signals A and B to be demodulated with good error rate performances. 12-. (canceled)3. A communication apparatus comprising:a modulator, which in operation, modulates a first data sequence and a second data sequence to generate a first modulated symbol sequence and a second modulated symbol sequence, respectively, and applies phase hopping to the second modulated symbol sequence, wherein an amount of the phase hopping is periodically switched in a time axis or a frequency axis; anda transmitter, which in operation, spatially-multiplexes the first modulated symbol sequence and the phase hopped second modulated symbol and transmits the spatially-multiplexed symbol sequences.4. The communication apparatus according to claim 3 , wherein the phase hopping is not applied to the first modulated symbol sequence.5. The communication apparatus according to claim 3 , comprisingan LDPC encoder which, in operation, performs LDPC encoding on a signal to generate the first data sequence and the second data sequence.6. The communication apparatus according to claim 3 , wherein the transmitter comprises a plurality of antennas claim 3 , and the spatially-multiplexed symbol sequences are transmitted by using a directional beam.7. A communication method comprising:modulating a first data sequence and a second data sequence to ...

Transmission Apparatus and Method, and Reception Apparatus and Method

Modulated signal A is transmitted from a first antenna, and modulated signal B is transmitted from a second antenna. As modulated signal B, modulated symbols S2(i) and S2(i+1) obtained from different data are transmitted at time i and time i+1 respectively. In contrast, as modulated signal A, modulated symbols S1(i) and S1(i)′ obtained by changing the signal point arrangement of the same data are transmitted at time i and time i+1 respectively. As a result the reception quality can be changed intentionally at time i and time i+1, and therefore using the demodulation result of modulated signal A of a time when the reception quality is good enables both modulated signals A and B to be demodulated with good error rate performances.

METHODS AND APPARATUS FOR TRANSMITTING MODULATION SIGNALS

A plurality of multicarrier signals is generated. Each of the plurality of multicarrier signals includes a pilot symbol sequence at a same temporal point in each multicarrier signal. Each pilot symbol sequence includes a plurality of pilot symbols with non-zero amplitude. The pilot symbol sequences are orthogonal to each other at the same temporal point. A quantity of the plurality of pilot symbols in each pilot symbol sequence is greater than or equal to a quantity of the plurality of multicarrier signals to be transmitted. The plurality of multicarrier signals are transmitted in an identical frequency band from a plurality of antennas. The plurality of antennas includes two, three, or four antennas. 1. A method of transmitting multicarrier signals comprising:generating a plurality of multicarrier signals, each of the plurality of multicarrier signals including a pilot symbol sequence at a same temporal point in each multicarrier signal, and each pilot symbol sequence having a plurality of pilot symbols with non-zero amplitude,wherein the pilot symbol sequences are orthogonal to each other at the same temporal point, andwherein a quantity of the plurality of pilot symbols in each pilot symbol sequence is greater than or equal to a quantity of the plurality of multicarrier signals to be transmitted; andtransmitting, in an identical frequency band, the plurality of multicarrier signals, including respective independent transmission data, from a plurality of antennas,wherein the plurality of antennas comprises a number of antennas that is greater than or equal to a number of independent multicarrier signals.2. The method of claim 1 , wherein the plurality of pilot symbols are for estimating a frequency offset and/or for synchronization.3. The method of claim 1 , wherein the plurality of pilot symbols each include real or complex numbers.4. The method of claim 1 , wherein the plurality of pilot symbols includes four claim 1 , eight claim 1 , or more pilot symbols.5. ...

WIRELESS COMMICATION BASE STATION APPARATUS, WIRELESS COMMUNICATION TERMINAL, COMMUNICATION METHOD OF A WIRELESS COMMUNICATION BASE STATION APPARATUS AND COMMUNICATION METHOD OF A WIRELESS COMMUNICATION TERMINAL

A transmitter apparatus wherein a simple structure is used to successfully suppress the degradation of error rate performance that otherwise would be caused by fading or the like. There are included encoding parts that encode transport data; a mapping part that performs such a mapping that encoded data sequentially formed by the encoding parts are not successively included in the same symbol, thereby forming data symbols; and a symbol interleaver that interleaves the data symbols. In this way, a low computational complexity can be used to perform an interleaving process equivalent to a bit interleaving process to effectively improve the reception quality at a receiving end. 1. A wireless communication base station apparatus comprising:an encoder, which in operation, performs a determined encoding process on transmit data to generate two codeword signals;a modulator, which in operation, generates a first mapping signal and a second mapping signal by mapping each of the two codeword signals on one of an I-Q plane corresponding to a QPSK scheme and an I-Q plane corresponding to a 16QAM scheme, performs a phase-rotation on the first mapping signal and the second mapping signal, and combines the phase-rotated first mapping signal and the phase-rotated second mapping signal to generate a combined signal;an OFDM signal generator, which in operation, performs an IFFT process on the combined signal to generate an OFDM signal; anda transmitter, which in operation, transforms the OFDM signal to a radio frequency signal and transmits the radio frequency signal.2. The wireless communication base station apparatus according to claim 1 , wherein the modulator claim 1 , in operation claim 1 , generates the first mapping signal and the second mapping signal by mapping each of the two codeword signals on the I-Q plane corresponding to the QPSK scheme.3. The wireless communication base station apparatus according to claim 1 , wherein the modulator claim 1 , in operation claim 1 , ...

TRANSMISSION AND RECEPTION SIGNAL PROCESSOR AND METHOD

A transmission apparatus includes a plurality of orthogonal frequency division multiplexing (OFDM) modulation signal generators, which generate a first OFDM modulation signal and a second OFDM modulation signal. The transmission apparatus also includes a transmitter that transmits the first OFDM modulation signal from a first antenna and the second OFDM modulation signal from a second antenna, in an identical frequency band. A reception apparatus is provided, which includes a plurality of antennas that receive a plurality of OFDM modulation signals; a plurality of OFDM demodulators that transform the plurality of OFDM modulation signals to a plurality of reception signals using Fourier transform; an estimator that outputs a distortion estimation signal using one or more symbols for demodulation included in the plurality of reception signals; and a demodulator that compensates for distortion of the reception signals using the distortion estimation signal and demodulates a data symbol included in the reception signals. 1. A transmission signal processor comprising: [ inserting a first symbol for demodulation in a first plurality of subcarriers at a first time and in a second plurality of sub-carriers at a second time; and', 'inserting a symbol, having both an in-phase (I) component and a quadrature-phase (Q) component in an I-Q plane of zero, in the second plurality of sub-carriers at the first time and in the first plurality of sub-carriers at the second time;, '(i) generate a first OFDM modulation signal by, inserting a symbol, having both an in-phase (I) component and a quadrature-phase (Q) component in the I-Q plane of zero, in the first plurality of subcarriers at the first time and in the second plurality of sub-carriers at the second time; and', 'inserting a second symbol for demodulation in the second plurality of sub-carriers at the first time and in the first plurality of sub-carriers at the second time; and, '(ii) generate a second OFDM modulation signal by ...

METHOD OF DEMODULATING MODULATION SIGNALS

A method of demodulating a plurality of multiplexed modulation signals is provided, including: i) inputting the plurality of multiplexed modulation signals, each of which being outputted from a plurality of outputs of a communication partner, wherein each modulation signal in the multiplexed modulation signals includes a pilot symbol sequence consisting of a plurality of pilot symbols used for demodulation, ii) estimating respective channels of the multiplexed modulation signals based on one or more of the pilot symbol sequences; and iii) demodulating said each modulation signal in the plurality of multiplexed modulation signals based on the channel estimation. Each of the pilot symbol sequences is inserted at a same temporal point in said each modulation signal among the multiplexed modulation signals. The pilot symbol sequences are orthogonal to each other with zero cross correlation among the modulation signals in the multiplexed modulation signals, and each pilot symbol has a non-zero amplitude. 1. A method of transmitting modulation signals , the method comprising:generating a plurality of modulation signals each of which is to be transmitted from a different one of a plurality of antennas,wherein each modulation signal includes a pilot symbol sequence and/or a pilot subcarrier including a plurality of pilot symbols used for demodulation;inserting each of the pilot symbol sequences and/or pilot subcarriers at the same temporal point in each modulation signal,wherein the pilot symbol sequences and/or pilot subcarriers are orthogonal to each other, each pilot symbol having a non-zero amplitude,the quantity of the plurality of pilot symbols in each pilot symbol sequence and/or pilot subcarrier being greater than a quantity of the plurality of modulation signals to be transmitted; andtransmitting in an identical frequency band the plurality of modulation signals, each including different transmission data and one of the pilot symbol sequences and/or pilot ...

TRANSMISSION SIGNAL GENERATOR, TRANSMISSION SIGNAL GENERATING METHOD, RECEPTION SIGNAL GENERATOR, AND RECEPTION SIGNAL GENERATING METHOD

Modulated signal A is transmitted from a first antenna, and modulated signal B is transmitted from a second antenna. As modulated signal B, modulated symbols S2(i) and S2(i+1) obtained from different data are transmitted at time i and time i+1 respectively. In contrast, as modulated signal A, modulated symbols S1(i) and S1(i)′ obtained by changing the signal point arrangement of the same data are transmitted at time i and time i+1 respectively. As a result the reception quality can be changed intentionally at time i and time i+1, and therefore using the demodulation result of modulated signal A of a time when the reception quality is good enables both modulated signals A and B to be demodulated with good error rate performances. 1. A transmission signal generator comprising:a signal processing section configured to generate a first modulated symbol sequence and a second modulated symbol sequence, the first modulated symbol sequence obtained by sequentially mapping a first set of bits to signal points in an in-phase and quadrature plane using a first mapping pattern that is based on a predetermined modulation scheme, and the second modulated symbol sequence obtained by sequentially mapping a second set of bits to signal points in the in-phase and quadrature plane using a second mapping pattern that is based on the predetermined modulation scheme; andan outputter configured to output the first modulated symbol sequence and the second modulated symbol sequence in a same frequency and at a same time,wherein:the first mapping pattern includes an amplitude obtained by changing an amplitude of a third mapping pattern, the third mapping pattern depending on the predetermined modulation scheme;the second mapping pattern includes an amplitude obtained by changing an amplitude of the third mapping pattern and a phase obtained by changing a phase of the third mapping pattern toward a predetermined direction; andsignal points obtained by mapping a predetermined set of bits in ...

TRANSMISSION APPARATUS, RECEPTION APPARATUS AND DIGITAL RADIO COMMUNICATION METHOD

A transmission method includes modulating a transmission signal using a modulation scheme selected from a plurality of modulation schemes, to generate a first symbol sequence and generating at least one second symbol including a pilot symbol generated using a PSK modulation scheme. The method includes changing an insertion interval of the second symbol to be inserted in the first symbol sequence, to generate a modulation signal and transmitting the modulation signal. The second symbol is configured for synchronization in a reception apparatus.

RADIO COMMUNICATION APPARATUS CAPABLE OF SWITCHING MODULATION SCHEMES

A radio communication apparatus includes a QPSK modulator that modulates transmission data to produce a QPSK modulation signal and a 64QAM modulator that modulates transmission data to produce a 64QAM modulation signal. A radio transmitter receives the QPSK modulation signal and the 64QAM modulation signal and outputs a transmission signal. An average transmission power of the QPSK modulation signal and the 64QAM modulation signal are within a predetermined output power range. 1. A radio communication apparatus , comprising:a QPSK modulator to modulate transmission data to produce a QPSK modulation signal;a 64QAM modulator to modulate transmission data to produce a 64QAM modulation signal; anda radio transmitter to receive the QPSK modulation signal and the 64QAM modulation signal and output a transmission signal,wherein an average transmission power of the QPSK modulation signal and the 64QAM modulation signal are within a predetermined output power range.2. The radio communication apparatus according to claim 1 , further comprising a receiver to receive information regarding a radio wave propagation environment transmitted by a communication party claim 1 , wherein the QPSK modulator claim 1 , the 64QAM modulator claim 1 , and the average transmission powers are controlled based upon the received information.3. The radio communication apparatus according to claim 2 , wherein the received information includes information regarding communications traffic.4. The radio communication apparatus according to claim 2 , wherein the QPSK modulator is selectable using a control signal and the 64QAM modulator is selectable using a control signal.5. The radio communication apparatus according to claim 1 , wherein the radio communication apparatus is configured to use orthogonal frequency division multiplexing (OFDM).6. The radio communication apparatus according to claim 5 , wherein the transmission data includes a frame having one or more preambles claim 5 , one or more ...

TRANSMISSION METHOD, TRANSMISSION APPARATUS, RECEPTION METHOD AND RECEPTION APPARATUS

A low-density parity check convolution code (LDPC-CC) is made, and a signal sequence is sent after being subjected to an error-correcting encodement using the low-density parity check convolution code. In this case, a low-density parity check code of a time-variant period (3g) is created by linear operations of first to 3g-th (letter g designates a positive integer) parity check polynomials and input data. 2. The transmitting method according to claim 1 , wherein the integer n used in the coding rate is 2.4. The transmitting apparatus according to claim 3 , wherein the integer n used in the coding rate is 2. This is a continuation application of application Ser. No. 15/821,011 filed Nov. 22, 2017, which is a continuation application of application Ser. No. 14/994,986 filed Jan. 13, 2016, which is a continuation application of application Ser. No. 14/255,651 filed Apr. 17, 2014, which is a continuation application of application Ser. No. 12/679,740 filed Mar. 24, 2010, now U.S. Pat. No. 8,745,471 issued Jun. 3, 2014, which is a 371 application of PCT/JP2008/002701 filed Sep. 26, 2008, which is based on Japanese Application No. 2007-256567 filed Sep. 28, 2007, Japanese Application No. 2007-340963 Dec. 28, 2007, Japanese Application No. 2008-000844 filed Jan. 7, 2008, Japanese Application No. 2008-000847 filed Jan. 7, 2008, Japanese Application No. 2008-015670 filed Jan. 25, 2008, Japanese Application No. 2008-045290 filed Feb. 26, 2008, Japanese Application No. 2008-061749 filed Mar. 11, 2008, and Japanese Application No. 2008-149478 filed Jun. 6, 2008, the entire contents of each of which are incorporated by reference herein.The present invention relates to a Low-Density Parity-Check Convolutional Code (LDPC-CC) encoding method, encoder, and decoder.In recent years, attention has been attracted to a Low-Density Parity-Check (LDPC) code as an error correction code that provides high error correction capability with a feasible computational complexity. Due to its high ...

TRANSMISSION APPARATUS AND METHOD, AND RECEPTION APPARATUS AND METHOD

Modulated signal A is transmitted from a first antenna, and modulated signal B is transmitted from a second antenna. As modulated signal B, modulated symbols S(i) and S(i+1) obtained from different data are transmitted at time i and time i+1 respectively. In contrast, as modulated signal A, modulated symbols S(i) and S(i)′ obtained by changing the signal point arrangement of the same data are transmitted at time i and time i+1 respectively. As a result the reception quality can be changed intentionally at time i and time i+1, and therefore using the demodulation result of modulated signal A of a time when the reception quality is good enables both modulated signals A and B to be demodulated with good error rate performances. 1. A transmitting apparatus comprising:a signal processor, which in operation, generates a first modulated symbol sequence and a second modulated symbol sequence, the first modulated symbol sequence obtained by sequentially mapping with a first mapping pattern that is based on a determined modulation scheme, the second modulated symbol sequence obtained by selecting, sequentially for each second modulated symbol, from the first mapping pattern and a plurality of second mapping patterns that are based on the determined modulation scheme and sequentially mapping with a selected mapping pattern; anda plurality of antennas, which in operation, transmit the first modulated symbol sequence and the second modulated symbol sequence in multi-beam signals in a same frequency and at a same time,wherein:the first mapping pattern is a mapping pattern having a different phase from phases of the plurality of second mapping patterns, andthe plurality of second mapping patterns are regularly varied the first mapping pattern for each second modulated symbol.2. A transmitting method comprising:generating, by a processor, a first modulated symbol sequence and a second modulated symbol sequence, the first modulated symbol sequence obtained by sequentially mapping ...

METHODS AND APPARATUS FOR TRANSMITTING MODULATION SIGNALS

A plurality of modulation signals is generated. Each of the plurality of modulation signals includes a pilot symbol sequence having a plurality of pilot symbols. Each pilot symbol sequence is inserted at a same temporal point in each modulation signal, and each pilot symbol in the pilot symbol sequence has a non-zero amplitude. A quantity of the plurality of pilot symbols in each pilot symbol sequence is greater than or equal to a quantity of the plurality of modulation signals to be transmitted. The plurality of modulation signals are transmitted in an identical frequency band from a plurality of antennas. Each of the transmitted plurality of modulation signals includes transmission data and one of the pilot symbol sequences. 1. A method of transmitting modulation signals , the method comprising:generating a plurality of modulation signals, each of the plurality of modulation signals including a pilot symbol sequence having a plurality of pilot symbols;inserting each pilot symbol sequence at a same temporal point in each modulation signal, each pilot symbol in the pilot symbol sequence having a non-zero amplitude,a quantity of the plurality of pilot symbols in each pilot symbol sequence being greater than or equal to a quantity of the plurality of modulation signals to be transmitted; andtransmitting in an identical frequency band the plurality of modulation signals, each of the plurality of modulation signals including transmission data and one of the pilot symbol sequences, from a plurality of antennas.2. The method of claim 1 , further comprising using the plurality of pilot symbols for estimating a frequency offset and/or for synchronization.3. The method of claim 1 , wherein the plurality of pilot symbols each include real or complex numbers.4. The method of claim 1 , wherein each of the plurality of modulation signals includes different transmission data.5. The method of claim 1 , wherein a number of the plurality of antennas is two claim 1 , three claim 1 , ...

RECEPTION APPARATUS AND ASSOCIATED METHOD OF RECEIVING ENCODED DATA

A transmission apparatus includes an encoder that codes a data sequence with a parity check matrix, wherein the data sequence includes a final information bit sequence and virtual information bits, and outputs the final information bit sequence and a parity sequence, as LDPC codes, and a transmitter that transmits the LDPC codes as a transmission data. A column length of the parity check matrix is longer than a total length of the final information bit sequence and the parity sequence, by a length of the virtual information bits that are set to “0” and are not transmitted. The total length of the final information bit sequence and the parity sequence has a sequence length corresponding to a length from a first column to a predetermined column of the parity check matrix. The encoder generates the LDPC codes by using the first column to the predetermined column among one or more column(s) of the parity check matrix. 1. A power line transmission apparatus comprising:an encoder, which, in operation, outputs a parity sequence and an information sequence, the parity sequence comprising low-density parity-check (LDPC) encoded data obtained by LDPC-encoding the information sequence using a parity check matrix in which “n” number of (where n is an integer equal to or greater than 1) parity check equation groups including a plurality of parity check polynomials are arranged, each of the plurality of parity check polynomials satisfying zero; anda transmitter, which, in operation, outputs a modulation signal obtained by modulating the LDPC encoded data, to a power line, whereinthe parity sequence is generated by using a first column to a predetermined column of the parity check matrix for an information sequence having a sequence length that corresponds to a length from the first column to the predetermined column among one or more column(s) of the parity check matrix, and {'br': None, 'i': A', 'D', 'X', 'D', 'A', 'D', 'X', 'D', 'A', 'D', 'X', 'D', 'B', 'D', 'P', 'D', 'k=j', 'g ...

TRANSMISSION SIGNAL GENERATING APPARATUS AND METHOD, AND RECEPTION DATA GENERATING APPARATUS AND METHOD

A transmitter apparatus wherein a relatively simple structure is used to suppress burst errors without changing the block sizes of encoded blocks even when the number of modulation multi-values is increased. An encoding part subjects transport data to a block encoding process to form block encoded data. A modulating part modulates the block encoded data to form data symbols; and an arranging (interleaving) part arranges (interleaves) the block encoded data in such a manner that the intra-block encoded data of the encoded blocks, which include their respective single different data symbol, get together, and then supplies the arranged (interleaved) block encoded data to the modulating part. In this way, there can be provided a transmitter apparatus wherein a relatively simple structure is used to suppress burst errors without changing the block sizes of encoded blocks even when the number of modulation multi-values is increased. 1. A transmission signal generating apparatus comprising:an encoder that performs error correction encoding processing on transmit data comprising a plurality of bits to form a plurality of error correction encoding data each comprising a plurality of bits;an interleaver that interleaves bits of the plurality of error correction encoding data; anda modulator that modulates the interleaved bits of the plurality of error correction encoding data using a QPSK modulation scheme or a 16QAM modulation scheme to generate a plurality of modulation symbols, wherein:the modulator generates the plurality of modulation symbols, using a first error correction encoding data for the QPSK modulation scheme, and, using the first error correction encoding data and a second error correction encoding data for the 16QAM modulation scheme, at a first time slot; andthe interleaver interleaves the bits for every two bits in the QPSK modulation scheme and interleaves the bits for every four bits in the 16QAM modulation scheme.2. The transmission signal generating ...

TRANSMISSION METHOD AND TRANSMISSION APPARATUS

A transmission apparatus includes processing circuitry that generates a first data sequence representing first data or a second data sequence representing second data different from the first data and selects the first data sequence as an output data sequence. A modulation scheme is determined from a plurality of modulation schemes, and the output data sequence is modulated with the determined modulation scheme. Transmission circuitry transmits the modulated output data sequence. A first time interval associated with selecting the first data sequence for the output data sequence is longer than a second time interval associated with determining the determined modulation scheme. 1. A transmission apparatus comprising: generate a first data sequence representing first data or a second data sequence representing second data different from the first data;', 'select the first data sequence as an output data sequence;', 'determine a modulation scheme from a plurality of modulation schemes; and', 'modulate the output data sequence with the determined modulation scheme, and, 'processing circuitry totransmission circuitry to transmit the modulated output data sequence,wherein a first time interval associated with selecting the first data sequence for the output data sequence is longer than a second time interval associated with determining the determined modulation scheme.2. A method for a transmission apparatus comprising the steps of:generating a first data sequence representing first data or a second data sequence representing second data different from the first data;selecting the first data sequence as an output data sequence;determining a modulation scheme from a plurality of modulation schemes;modulating the output data sequence using the determined modulation scheme; andtransmitting, by transmission circuitry, the modulated output data sequence,wherein a first time interval associated with selecting the first data sequence for the output data sequence is longer than a ...

OFDM FRAME COMMUNICATION METHOD AND APPARATUS

A first orthogonal frequency division multiplexing (OFDM) frame signal is generated that includes a grid of multiple frequency subcarriers and multiple time periods. An OFDM symbol is transmitted using multiple frequency subcarriers during a time period and includes known reference OFDM symbols assigned to corresponding time-frequency resource elements in the grid. Each resource element is defined by a one of the multiple frequency subcarriers and one of the multiple time periods. A second orthogonal frequency division multiplexing (OFDM) frame signal is generated that includes a grid of multiple frequency subcarriers and multiple time periods and includes known reference OFDM symbols assigned to corresponding time-frequency resource elements in the grid. The time-frequency resource elements in the grid assigned to the known reference OFDM symbols in the first OFDM frame signal are different from the time-frequency resource elements in the grid assigned to the known reference OFDM symbols in the second OFDM frame signal. The first OFDM frame signal is converted to a first radio signal and the second OFDM frame signal to a second radio signal. The first radio signal is transmitted from a first antenna and the second radio signal from a second, different antenna. 1receiving a first radio signal transmitted from a first antenna at a transmitter and a second radio signal transmitted from a second antenna at the transmitter different from the first antenna,converting the first radio signal to a first orthogonal frequency division multiplexing (OFDM) frame signal and the second radio signal to a second OFDM frame signal,wherein the first OFDM frame signal includes a grid of multiple frequency subcarriers and multiple time periods, each time period with the multiple frequency carriers corresponding to a first OFDM symbol such that the first OFDM frame includes multiple first OFDM symbols, where a first OFDM symbol is carried on multiple frequency subcarriers during a time ...

Transmission and reception signal processor and method

A transmission apparatus includes a plurality of orthogonal frequency division multiplexing (OFDM) modulation signal generators, which generate a first OFDM modulation signal and a second OFDM modulation signal. The transmission apparatus also includes a transmitter that transmits the first OFDM modulation signal from a first antenna and the second OFDM modulation signal from a second antenna, in an identical frequency band. A reception apparatus is provided, which includes a plurality of antennas that receive a plurality of OFDM modulation signals; a plurality of OFDM demodulators that transform the plurality of OFDM modulation signals to a plurality of reception signals using Fourier transform; an estimator that outputs a distortion estimation signal using one or more symbols for demodulation included in the plurality of reception signals; and a demodulator that compensates for distortion of the reception signals using the distortion estimation signal and demodulates a data symbol included in the reception signals.

INFORMATION RECORDING DEVICE, ACCESS DEVICE, AND ACCESS METHOD

An information recording device stores data. The information recording device includes a first bus interface that transmits data to and receives data from an access device according to a first interface scheme, the access device accessing the information recording device, and a second bus interface that transmits data to and receives data from the access device according to a second interface scheme. The first bus interface and the second bus interface only share wiring of a power supply and wiring of a ground. 1. An information recording device that stores data , the information recording device comprising:a first bus interface that transmits data to and receives data from an access device according to a first interface scheme, the access device accessing the information recording device; anda second bus interface that transmits data to and receives data from the access device according to a second interface scheme,wherein the first bus interface and the second bus interface only share wiring of a power supply and wiring of a ground.2. The information recording device according to claim 1 , wherein a clock to be used in the second interface scheme is supplied by superimposing the clock onto wiring for data transmission and reception claim 1 , the wiring being provided in the second bus interface.3. The information recording device according to claim 1 , wherein a clock to be used in the second interface scheme is supplied by using dedicated clock wiring provided in the second bus interface.4. The information recording device according to claim 3 , further comprisingdedicated wiring that controls whether to supply the clock.5. The information recording device according to claim 1 , wherein when a clock to be used in the second interface scheme is supplied by using dedicated clock wiring provided in the second bus interface claim 1 , only one of two pieces of wiring of a differential clock pair is connected to the information recording device claim 1 , the ...

TRANSMISSION APPARATUS AND METHOD, AND RECEPTION APPARATUS AND METHOD

Modulated signal A is transmitted from a first antenna, and modulated signal B is transmitted from a second antenna. As modulated signal B, modulated symbols S() and S(i+1) obtained from different data are transmitted at time i and time i+1 respectively. In contrast, as modulated signal A, modulated symbols S() and S()′ obtained by changing the signal point arrangement of the same data are transmitted at time i and time i+1 respectively. As a result the reception quality can be changed intentionally at time i and time i+1, and therefore using the demodulation result of modulated signal A of a time when the reception quality is good enables both modulated signals A and B to be demodulated with good error rate performances. 1. A transmitting apparatus comprising:a modulator, which in operation, modulates a first data sequence to a first modulated symbol sequence and a second data sequence to a second modulated symbol sequence;a signal processor, which in operation, generates the first modulated symbol sequence and the second modulated symbol sequence, the first modulated symbol sequence being obtained by sequentially mapping with a first mapping pattern that is based on a determined modulation scheme, the second modulated symbol sequence being obtained by selecting, sequentially for each second modulated symbol, from the first mapping pattern and a plurality of second mapping patterns that are based on the determined modulation scheme and sequentially mapping with a selected mapping pattern; anda plurality of antennas, which in operation, transmit the first modulated symbol sequence and the second modulated symbol sequence in multi-beam signals in a same frequency and at a same time,wherein:the first mapping pattern is a mapping pattern having a different phase from phases of the plurality of second mapping patterns, andthe plurality of second mapping patterns are mapping patterns that a phase of the first mapping pattern is regularly changed between the second ...

TRANSMISSION SIGNAL GENERATION METHOD, TRANSMISSION SIGNAL GENERATION APPARATUS, RECEPTION SIGNAL GENERATION METHOD, AND RECEPTION SIGNAL GENERATION APPARATUS

Of any one of a transmission method X of transmitting modulated signal A and modulated signal B including the same data from a plurality of antennas and a transmission method Y of transmitting modulated signal A and modulated signal B having different data from the plurality of antennas, a base station apparatus does not change the transmission method during data transmission and changes only the modulation scheme. The base station apparatus transmits modulated signal A and modulated signal B to a communication terminal apparatus using the determined transmission method and modulation scheme. In this way, it is possible to improve data transmission efficiency when transmitting data using the plurality of antennas. 1. A transmission signal generation method comprising:selecting, by a processor, either a first signal generation scheme for generating a plurality of signals including same data, or a second signal generation scheme for generating a plurality of signals including different data;selecting a modulation scheme, for modulating the same data and the different data, among a plurality of modulation schemes; andcontrolling the selecting between the first signal generation scheme and the second signal generation scheme with a longer interval than the selecting among the modulation schemes.2. The transmission signal generation method according to claim 1 , wherein each of the plurality of signals generated using the first signal generation scheme or the second signal generation scheme is transmitted from a plurality of antennas.3. The transmission signal generation method according to claim 1 , wherein the plurality of signals in the first signal generation scheme are generated using a space-time block coding.4. The transmission signal generation method according to claim 1 , wherein each of the plurality of signals in the first signal generation scheme is transmitted using a Cyclic Delay Diversity (CDD) from a plurality of antennas.5. The transmission signal ...

TRANSMISSION SIGNAL GENERATION APPARATUS, TRANSMISSION SIGNAL GENERATION METHOD, RECEPTION SIGNAL APPARATUS, AND RECEPTION SIGNAL METHOD

MIMO-OFDM communication is provided which allows high accuracy estimation of frequency offset, high accuracy estimation of a transmission path fluctuation and high accuracy synchronization/signal detection. Pilot symbol mapping is provided for forming pilot carriers by assigning orthogonal sequences to corresponding subcarriers among OFDM signals which are transmitted at the same time from respective antennas in the time domain. Even when pilot symbols are multiplexed among a plurality of channels (antennas), this allows frequency offset/phase noise to be estimated with high accuracy. 1. A transmission signal generation apparatus comprising:a mapper configured to generate one or more transmission signals, each transmission signal including a data frame having preamble information, pilot information, and data information, an associated preamble multiplied by a factor so that an average reception power of the associated preamble corresponds to an average reception power of the data information received with the associated preamble,', 'plural pilot symbol sequences; and, 'wherein each of the one or more transmission signals includes 'generate for each of the one or more transmission signals a corresponding Orthogonal Frequency Division Multiplexed (OFDM) signal for transmission by a corresponding one of one or more antennas by Inverse Fourier transforming each of the transmission signals,', 'an Inverse Fourier transformer configured towherein: the pilot symbol sequences in corresponding pilot carriers during a first time period, and', 'sets of the pilot carriers in a same carrier position in the OFDM signal, and', 'wherein the plural pilot symbol sequences are all orthogonal to each other., 'the Inverse Fourier transformer is configured to arrange2. The transmission signal generation apparatus of claim 1 , wherein the one or more antennas includes one claim 1 , two claim 1 , three claim 1 , or four antennas.3. The transmission signal generation apparatus of claim 1 , ...

RADIO TRANSMISSION APPARATUS AND METHODS

A radio transmission apparatus includes a first antenna, a second antenna, and circuitry configured, based on information associated with an estimated communications channel condition, to generate a single modulation signal or a plurality of modulation signals based on the estimated communications channel condition information, and to (i) transmit the single modulation signal from the first antenna or (ii) transmit the plurality of modulation signals which include different information from each other over an identical frequency band from the first antenna and the second antenna at an identical temporal point. The single modulation signal and the plurality of modulation signals contain parameter information indicating a number of modulation signals transmitted at the same time. 1. A radio transmission apparatus comprising:a first antenna and a second antenna; generate a single modulation signal or a plurality of modulation signals based on the estimated communications channel condition information, and', 'transmit the single modulation signal from the first antenna or transmit the plurality of modulation signals which include different information from each other over an identical frequency band from the first antenna and the second antenna at an identical temporal point; and, 'circuitry configured, based on information associated with an estimated communications channel condition, towherein the single modulation signal and the plurality of modulation signals contain parameter information indicating a number of modulation signals transmitted at the same time.2. The radio transmission apparatus of claim 1 , wherein the information associated with an estimated communications channel condition is estimated based on a modulation signal transmitted when a communication starts.3. The radio transmission apparatus of claim 1 , further comprising a receiver configured to receive from a communications partner device the information associated with an estimated communications ...

Transmission apparatus, reception apparatus and digital radio communication method

A transmission apparatus and method include modulating a transmission signal using a first modulation scheme selected from a plurality of modulation schemes to generate a first symbol sequence. A second symbol, generated using a phase shift keying (PSK) modulation scheme, is inserted in the first symbol sequence to generate a first modulation signal for transmission. A second modulation signal is received that includes a third symbol generated using a PSK modulation scheme and inserted in a second symbol sequence generated using a second modulation scheme selected from the plurality of modulation schemes. The third symbol is extracted from the received modulation signal. A transmission path associated with the received modulation signal is estimated using the third symbol. A received data signal from the second symbol sequence included in the received modulation signal is output using the estimated transmission path.

RADIO TRANSMISSION APPARATUS AND METHODS

A radio transmission apparatus determines information indicative of an estimated communications channel condition and generates a single modulation signal or a plurality of modulation signals based on the estimated communications channel condition information. The single modulation signal is transmitted from a first antenna of a plurality of antenna or the plurality of modulation signals are transmitted from the first antenna and at least a second antenna of the plurality of antenna. The plurality of modulation signals include different information from each other and are transmitted over an identical frequency band and at an identical temporal point. The single modulation signal and the plurality of modulation signals contain parameter information indicating a number of modulation signals transmitted at the same time. 1. A radio transmission apparatus comprising: determine information indicative of an estimated communications channel condition;', 'generate, based on the information indicative of the estimated communications channel condition, a single modulation signal or a plurality of modulation signals; and', 'transmit, based on the generation of the single modulation signal or the plurality of modulation signals, the single modulation signal from a first antenna of the plurality of antenna or the plurality of modulation signals from the first antenna and at least a second antenna of the plurality of antenna,, 'a plurality of antenna and circuitry configured towherein the plurality of modulation signals include different information from each other and are transmitted over an identical frequency band and at an identical temporal point, andwherein the single modulation signal and the plurality of modulation signals contain parameter information indicating a number of modulation signals transmitted at the same time.2. The radio transmission apparatus of claim 1 , wherein the information indicative of the estimated communications channel condition is estimated ...

TRANSMISSION APPARATUS AND METHOD, AND RECEPTION APPARATUS AND METHOD

Modulated signal A is transmitted from a first antenna, and modulated signal B is transmitted from a second antenna. As modulated signal B, modulated symbols S() and S(+1) obtained from different data are transmitted at time i and time i+1 respectively. In contrast, as modulated signal A, modulated symbols S() and S()′ obtained by changing the signal point arrangement of the same data are transmitted at time i and time i+1 respectively. As a result the reception quality can be changed intentionally at time i and time i+1, and therefore using the demodulation result of modulated signal A of a time when the reception quality is good enables both modulated signals A and B to be demodulated with good error rate performances. 1. A transmitting apparatus comprising:a signal processor that generates a first modulated symbol sequence and a second modulated symbol sequence, the first modulated symbol sequence obtained by sequentially mapping a first bit sequence to signal points in an in-phase and quadrature plane using a first mapping pattern that is based on a predetermined modulation scheme, the second modulated symbol sequence obtained by selecting the first mapping pattern or a second mapping pattern that is based on the predetermined modulation scheme and sequentially mapping a second bit sequence to signal points in the in-phase and quadrature plane using a selected mapping pattern; anda plurality of antennas that transmit the first modulated symbol sequence and the second modulated symbol sequence in a same frequency and at a same time,wherein:the first mapping pattern is a mapping pattern having a phase that is changed from a phase of the second mapping pattern toward a predetermined direction.2. The transmitting apparatus according to claim 1 , whereina first position of a signal point obtained by mapping a predetermined bit sequence in the in-phase and quadrature plane according to the first mapping pattern and a second position of a signal point obtained by ...

ENCODING METHOD, ENCODER, AND DECODER

A low-density parity check convolution code (LDPC-CC) is made, and a signal sequence is sent after being subjected to an error-correcting encodement using the low-density parity check convolution code. In this case, a low-density parity check code of a time-variant period (3g) is created by linear operations of first to 3g-th (letter g designates a positive integer) parity check polynomials and input data. 2. The encoding method according to claim 1 , wherein the integer n is 2.3. The encoding method according to claim 1 , whereinthe generating step generates the low-density parity-check convolutional codeword by using the input data shifted by a shift register.4. An encoder structured to create a Low-Density Parity-Check Convolutional Code from a convolutional code claim 1 , the encoder comprising a parity calculation section that finds a parity sequence by the encoding method according to .5. The encoder according to claim 4 , whereinthe parity calculation section is structured to find the parity sequence by using the input data shifted by shift register. This is a continuation application of application Ser. No. 12/679,740 filed Mar. 24, 2010, which is a 371 application of PCTJP2008002701 filed Sep. 26, 2008, which is based on Japanese Application No. 2007-256567 filed Sep. 28, 2007, Japanese Application No. 2007-340963 Dec. 28, 2007, Japanese Application No. 2008-000844 filed Jan. 7, 2008, Japanese Application No. 2008-000847 filed. Jan. 7, 2008, Japanese Application No. 2008-015670 filed Jan. 25, 2008, Japanese Application No. 2008-045290 filed Feb. 26, 2008, Japanese Application No. 2008-061749 filed Mar. 11, 2008, and Japanese Application No. 2008-149478 filed Jun. 6, 2008, the entire contents of each of which are incorporated by reference herein.The present invention relates to a Low-Density Parity-Check Convolutional Code (LDPC-CC) encoding method, encoder, and decoder.In recent years, attention has been attracted to a Low-Density Parity-Check (LDPC) code ...

TRANSMITTING METHOD AND TRANSMITTING APPARATUS

A low-density parity check convolution code (LDPC-CC) is made, and a signal sequence is sent after being subjected to an error-correcting encodement using the low-density parity check convolution code. In this case, a low-density parity check code of a time-variant period (3g) is created by linear operations of first to 3g-th (letter g designates a positive integer) parity check polynomials and input data. 2. The transmitting method according to claim 2 , wherein:{'sub': #1,1,3', '#1,1,1', '#1,1,2', '#1,3', '#1,1', '#1,2, 'in the first parity check polynomials, a=0, (a%3, a%3) is either (1, 2) or (2, 1), and b=0, (b%3, b%3) is either (1, 2) or (2, 1);'}{'sub': #2,1,3', '#2,1,1', '#2,1,2', '#2,3', '#2,1', '#2,2, 'in the second parity check polynomials, a=0, (a%3, a%3) is either (1, 2) or (2, 1), and b=0, (b%3, b%3) is either (1, 2) or (2, 1); and'}{'sub': #3,1,3', '#3,1,1', '#3,1,2', '#3,3', '#3,1', '#3,2, 'in the third parity check polynomials, a=0, (a%3, a%3) is either (1, 2) or (2, 1), and b=0, (b%3, b%3) is either (1, 2) or (2, 1).'}4. The transmitting apparatus according to claim 3 , wherein:{'sub': #1,1,3', '#1,1,1', '#1,1,2', '#1,3', '#1,1', '#1,2, 'in the first parity check polynomials, a=0, (a%3, a%3) is either (1, 2) or (2, 1), and b=0, (b%3, b%3) is either (1, 2) or (2, 1);'}{'sub': #2,1,3', '#2,1,1', '#2,1,2', '#2,3', '#2,1', '#2,2, 'in the second parity check polynomials, a=0, (a%3, a%3) is either (1, 2) or (2, 1), and b=0, (b%3, b%3) is either (1, 2) or (2, 1); and'}{'sub': #3,1,3', '#3,1,1', '#3,1,2', '#3,3', '#3,1', '#3,2, 'in the third parity check polynomials, a=0, (a%3, a%3) is either (1, 2) or (2, 1), and b=0, (b%3, b%3) is either (1, 2) or (2, 1).'} This is a continuation application of application Ser. No. 14/255,651 filed Apr. 17, 2014, which is a continuation application of application Ser. No. 12/679,740 filed Mar. 24, 2010, now U.S. Pat. No. 8,745,471 issued Jun. 3, 2014, which is a 371 application of PCT/JP2008/002701 filed Sep. 26, 2008, ...

TRANSMISSION AND RECEPTION SIGNAL PROCESSOR AND METHOD

A transmission apparatus includes a plurality of orthogonal frequency division multiplexing (OFDM) modulation signal generators, which generate a first OFDM modulation signal and a second OFDM modulation signal. The transmission apparatus also includes a transmitter that transmits the first OFDM modulation signal from a first antenna and the second OFDM modulation signal from a second antenna, in an identical frequency band. A reception apparatus is provided, which includes a plurality of antennas that receive a plurality of OFDM modulation signals; a plurality of OFDM demodulators that transform the plurality of OFDM modulation signals to a plurality of reception signals using Fourier transform; an estimator that outputs a distortion estimation signal using one or more symbols for demodulation included in the plurality of reception signals; and a demodulator that compensates for distortion of the reception signals using the distortion estimation signal and demodulates a data symbol included in the reception signals. 1. A transmission apparatus comprising: (i) inserting symbols for demodulation in a first plurality of subcarriers and in a second plurality of sub-carriers at respectively different times; and', '(ii) inserting symbols, having both an in-phase (I) component and a quadrature-phase (Q) component in an I-Q plane of zero, in the second plurality of sub-carriers and in the first plurality of sub-carriers at times in which symbols for demodulation of other OFDM modulation signals are inserted, wherein at least two of the symbols for demodulation are inserted at continuous times in the first plurality of subcarriers; and, '(a) orthogonal frequency division multiplexing (OFDM) modulation signal generating circuitry which, in operation, generates each of a plurality of OFDM modulation signals by(b) transmitting circuity which, in operation, transmits the plurality of OFDM modulation signals, from respectively different antennas, in an identical frequency band.2 ...

Methods and apparatus for transmitting modulation signals

A plurality of multicarrier signals is generated. Each of the plurality of multicarrier signals includes a pilot symbol sequence at a same temporal point in each multicarrier signal. Each pilot symbol sequence includes a plurality of pilot symbols with non-zero amplitude. The pilot symbol sequences are orthogonal to each other at the same temporal point. A quantity of the plurality of pilot symbols in each pilot symbol sequence is greater than or equal to a quantity of the plurality of multicarrier signals to be transmitted. The plurality of multicarrier signals are transmitted in an identical frequency band from a plurality of antennas. The plurality of antennas includes two, three, or four antennas.

METHODS AND APPARATUS FOR TRANSMITTING MODULATION SIGNALS

A plurality of modulation signals is generated. Each of the plurality of modulation signals includes a pilot symbol sequence having a plurality of pilot symbols. Each pilot symbol sequence is inserted at a same temporal point in each modulation signal, and each pilot symbol in the pilot symbol sequence has a non-zero amplitude. A quantity of the plurality of pilot symbols in each pilot symbol sequence is greater than or equal to a quantity of the plurality of modulation signals to be transmitted. The plurality of modulation signals are transmitted in an identical frequency band from a plurality of antennas. Each of the transmitted plurality of modulation signals includes transmission data and one of the pilot symbol sequences. 1. A method of transmitting modulation signals , the method comprising:generating a plurality of modulation signals, each of the plurality of modulation signals including a pilot symbol sequence having a plurality of pilot symbols;inserting each pilot symbol sequence at a same temporal point in each modulation signal, each pilot symbol in the pilot symbol sequence having a non-zero amplitude, a quantity of the plurality of pilot symbols in each pilot symbol sequence being greater than or equal to a quantity of the plurality of modulation signals to be transmitted; andtransmitting in an identical frequency band the plurality of modulation signals, each of the plurality of modulation signals including transmission data and one of the pilot symbol sequences, from a plurality of antennas.2. The method of claim 1 , wherein the plurality of pilot symbols are for estimating a frequency offset and/or for synchronization.3. The method of claim 1 , wherein the plurality of pilot symbols each include real or complex numbers.4. The method of claim 1 , wherein each of the plurality of modulation signals includes different transmission data.5. The method of claim 1 , wherein a number of the plurality of antennas is two claim 1 , three claim 1 , or four ...

WIRELESS COMMUNICATION BASE STATION APPARATUS, WIRELESS COMMUNICATION TERMINAL, COMMUNICATION METHOD OF A WIRELESS COMMUNICATION BASE STATION APPARATUS AND COMMUNICATION METHOD OF A WIRELESS COMMUNICATION TERMINAL

A transmitter apparatus wherein a simple structure is used to successfully suppress the degradation of error rate performance that otherwise would be caused by fading or the like. There are included encoding parts that encode transport data; a mapping part that performs such a mapping that encoded data sequentially formed by the encoding parts are not successively included in the same symbol, thereby forming data symbols; and a symbol interleaver that interleaves the data symbols. In this way, a low computational complexity can be used to perform an interleaving process equivalent to a bit interleaving process to effectively improve the reception quality at a receiving end. 1. A wireless communication apparatus comprising:circuitry, which, in operation, generates two codeword signals by encoding data and generates a first mapping signal and a second mapping signal by mapping each of the two codeword signals on at least one of an in-phase/quadrature phase (I-Q) plane corresponding to a quadrature phase-shift keying (QPSK) scheme and an I-Q plane corresponding to a 16 quadrature amplitude modulation (16QAM) scheme, performs a phase-rotation on the second mapping signal by using a phase pattern selected from a plurality of phase-rotation patterns and combines the first mapping signal and the phase-rotated second mapping signal to generate a combined signal,wherein the phase pattern is same for both cases that (1) the second mapping signal is generated based on the QPSK scheme and that (2) the second mapping signal is generated based on the 16QAM scheme; anda transmitter, which is coupled to the circuitry and which, in operation, transmits the combined signal.2. The wireless communication apparatus according to claim 1 , wherein the first mapping signal and the second mapping signal are generated by mapping each of the two codeword signals on the I-Q plane corresponding to the QPSK scheme.3. The wireless communication apparatus according to claim 1 , wherein the first ...

RADIO TRANSMISSION APPARATUS AND METHODS

A radio transmission apparatus determines information indicative of an estimated communications channel condition and generates a single modulation signal or a plurality of modulation signals based on the estimated communications channel condition information. The single modulation signal from a first antenna or the plurality of modulation signals is(are) transmitted from the first antenna and a second antenna. The plurality of modulation signals include different information from each other and are transmitted over an identical frequency band and at an identical temporal point. The single modulation signal and the plurality of modulation signals contain parameter information indicating a number of modulation signals transmitted at the same time. 1. A radio transmission apparatus comprising circuitry configured to:determine information indicative of an estimated communications channel condition;generate, based on the information indicative of the estimated communications channel condition, a single modulation signal or a plurality of modulation signals; andtransmit, based on the generation of the single modulation signal or the plurality of modulation signals, the single modulation signal from a first antenna or the plurality of modulation signals from the first antenna and a second antenna,wherein the plurality of modulation signals include different information from each other and are transmitted over an identical frequency band and at an identical temporal point, andwherein the single modulation signal and the plurality of modulation signals contain parameter information indicating a number of modulation signals transmitted at the same time.2. The radio transmission apparatus of claim 1 , wherein the information indicative of the estimated communications channel condition is estimated based on a modulation signal transmitted when a communication starts.3. The radio transmission apparatus of claim 1 , wherein the determination of the information indicative of the ...

OFDM FRAME TRANSMISSION METHOD AND APPARATUS

A first orthogonal frequency division multiplexing (OFDM) frame signal is generated that includes a grid of multiple frequency subcarriers and multiple time periods. An OFDM symbol is transmitted using multiple frequency subcarriers during a time period and includes known reference OFDM symbols assigned to corresponding time-frequency resource elements in the grid, Each resource element is defined by a one of the multiple frequency subcarriers and one of the multiple time periods. A second orthogonal frequency division multiplexing (OFDM) frame signal is generated that includes a grid of multiple frequency subcarriers and multiple time periods and includes known reference OFDM symbols assigned to corresponding time-frequency resource elements in the grid. The time-frequency resource elements in the grid assigned to the known reference OFDM symbols in the first OFDM frame signal are different from the time-frequency resource elements in the grid assigned to the known reference OFDM symbols in the second OFDM frame signal. The first OFDM frame signal is converted to a first radio signal and the second OFDM frame signal to a second radio signal. The first radio signal is transmitted from a first antenna and the second radio signal from a second, different antenna. 1. A transmission method comprising:generating a first orthogonal frequency division multiplexing (OFDM) frame signal including a grid of multiple frequency subcarriers and multiple time periods, where an OFDM symbol is transmitted using multiple frequency subcarriers during a time period, and including known reference OFDM symbols assigned to corresponding time-frequency resource elements in the grid, each resource element being defined by a one of the multiple frequency subcarriers and one of the multiple time periods;generating a second orthogonal frequency division multiplexing (OFDM) frame signal including a grid of multiple frequency subcarriers and multiple time periods and including known reference ...

METHODS AND APPARATUS FOR TRANSMITTING MODULATION SIGNALS

A plurality of multicarrier signals is generated. Each of the plurality of multicarrier signals includes a pilot symbol sequence at a same temporal point in each multicarrier signal. Each pilot symbol sequence includes a plurality of pilot symbols with non-zero amplitude. A quantity of the plurality of pilot symbols in each pilot symbol sequence is greater than or equal to a quantity of the plurality of multicarrier signals to be transmitted. The plurality of multicarrier signals are transmitted in an identical frequency band from a plurality of antennas. 1. A method of transmitting multicarrier signals comprising:generating a plurality of multicarrier signals, each of the plurality of multicarrier signals including a pilot symbol sequence at a same temporal point in each multicarrier signal, and each pilot symbol sequence having a plurality of pilot symbols with non-zero amplitude,wherein a quantity of the plurality of pilot symbols in each pilot symbol sequence is greater than or equal to a quantity of the plurality of multicarrier signals to be transmitted; andtransmitting, in an identical frequency band, the plurality of multicarrier signals from a plurality of antennas.2. The method of claim 1 , wherein the plurality of pilot symbols are for estimating a frequency offset and/or for synchronization.3. The method of claim 1 , wherein the plurality of pilot symbols each include real or complex numbers.4. The method of claim 1 , wherein each of the plurality of multicarrier signals includes independent transmission data.5. The method of claim 1 , wherein a number of the plurality of antennas is two claim 1 , three claim 1 , or four antennas.6. The method of claim 1 , wherein the plurality of pilot symbols includes four claim 1 , eight claim 1 , or more pilot symbols.7. The method of claim 1 , wherein the pilot symbol sequences are orthogonal to each other at the same temporal point.8. The method of claim 1 , wherein the plurality of antennas includes a number of ...

RECEPTION APPARATUS AND ASSOCIATED METHOD OF RECEIVING ENCODED DATA

A transmission apparatus includes an encoder that codes a data sequence with a parity check matrix, wherein the data sequence includes a final information bit sequence and virtual information bits, and outputs the final information bit sequence and a parity sequence, as LDPC codes, and a transmitter that transmits the LDPC codes as a transmission data. A column length of the parity check matrix is longer than a total length of the final information bit sequence and the parity sequence, by a length of the virtual information bits that are set to “0” and are not transmitted. The total length of the final information bit sequence and the parity sequence has a sequence length corresponding to a length from a first column to a determined column of the parity check matrix. The encoder generates the LDPC codes by using the first column to the determined column among one or more column(s) of the parity check matrix. The present invention relates to an encoder, decoder and encoding method using a low-density parity-check convolutional code (LDPC-CC) supporting a plurality of coding rates.In recent years, attention has been attracted to a low-density parity-check (LDPC) code as an error correction code that provides high error correction capability with a feasible circuit scale. Because of its high error correction capability and ease of implementation, an LDPC code has been adopted in an error correction coding scheme for IEEE802.11n high-speed wireless LAN systems, digital broadcasting systems, and so forth.An LDPC code is an error correction code defined by low-density parity check matrix H. An LDPC code is a block code having a block length equal to number of columns N of parity check matrix H (e.g. see Non-Patent Literature 1, Non-Patent Literature 4, or Non-Patent Literature 11). A random-like LDPC code, array LDPC code, and QC-LDPC code (QC: Quasi-Cyclic) are proposed in Non-Patent Literature 2, Non-Patent Literature 3, and Non-Patent Literature 12, for example.However ...

WIRELESS COMMUNICATION APPARATUS AND WIRELESS COMMUNICATION METHOD

A wireless communication method is provided for a transmission apparatus that transmits an OFDM (orthogonal frequency division multiplexing) signal using a communication band that comprises a plurality of subcarrier groups each including a plurality of subcarriers. The method includes specifying which subcarrier group and how many subcarriers are to be used to transmit the OFDM signal and determining a configuration of a transmission frame, generating the OFDM signal by mapping data symbols according to the determined configuration of the transmission frame, and transmitting the generated OFDM signal. The number of subcarriers to be used to transmit the OFDM signal is variable, the OFDM signal may be generated using a plurality of modulation schemes including QPSK and 16QAM, and a plurality of mapping patterns are prepared for each of the plurality of modulation schemes. 1. A wireless communication method for a transmission apparatus that transmits an OFDM (orthogonal frequency division multiplexing) signal using a communication band that comprises a plurality of subcarrier groups each including a plurality of subcarriers , the method comprising:specifying which subcarrier group and how many subcarriers are to be used to transmit the OFDM signal and determining a configuration of a transmission frame;generating the OFDM signal by mapping data symbols according to the determined configuration of the transmission frame; andtransmitting the generated OFDM signal,characterized in that:a number of subcarriers to be used to transmit the OFDM signal is variable;the OFDM signal may be generated using a plurality of modulation schemes including QPSK and 16QAM;a plurality of mapping patterns are prepared for each of the plurality of modulation schemes, each mapping pattern indicating a combination of candidate positions of signal points on an IQ plane; andcombinations of candidate positions of signal points based on mapping patterns other than a first mapping pattern included ...

TRANSMISSION DEVICE, RECEPTION DEVICE, AND RADIO COMMUNICATION METHOD

A transmitting apparatus includes an OFDM modulator that generates a first modulation symbol by modulating a first information signal using a first modulation scheme, a signal point of the first modulated information signal being arranged at a first position in an in-phase quadrature-phase plane and a second modulation symbol by modulating a second information signal using the first modulation scheme, and by changing a second position at which a signal point of the modulated second information signal is arranged to a third position in the in-phase quadrature-phase plane, wherein the third position is different from the first position. An OFDM modulation signal includes the first modulation symbol and the second modulation symbol, wherein the OFDM modulation signal comprises a plurality of subcarriers. A transmitter transmits the OFDM modulation signal. 1. A transmitting apparatus comprising:an OFDM modulator that generatesa first modulation symbol by modulating a first information signal using a first modulation scheme, a signal point of the first modulated information signal being arranged at a first position in an in-phase quadrature-phase plane,a second modulation symbol by modulating a second information signal using the first modulation scheme, and by changing a second position at which a signal point of the modulated second information signal is arranged to a third position in the in-phase quadrature-phase plane, wherein the third position is different from the first position, andan OFDM modulation signal including the first modulation symbol and the second modulation symbol, wherein the OFDM modulation signal comprises a plurality of subcarriers′, anda transmitter that transmits the OFDM modulation signal.2. The transmitting apparatus according to claim 1 , wherein the first modulation symbol and the second modulation symbol are arranged in a same subcarrier in the OFDM modulation signal.3. A transmission method comprising:generating a first modulation symbol ...

TRANSMISSION SIGNAL GENERATION APPARATUS, TRANSMISSION SIGNAL GENERATION METHOD, RECEPTION SIGNAL APPARATUS, AND RECEPTION SIGNAL METHOD

A transmission apparatus maps a first stream of input data to first complex symbols in serial format and convert them into first complex symbols in parallel format. They are inverse Fourier transformed into OFDM signals associated with multiple subcarriers that are transmitted via a first antenna over the multiple subcarriers in a same frequency band over a same time period that includes a same set of time slots. First pilot information is transmitted via a first antenna on a first one of a plurality of pilot subcarriers during the same set of time slots, and second pilot information is sent via a first antenna on a second one of a plurality of pilot subcarriers during the same set of time slots. The second pilot information is different from the first pilot information. A second stream of input data is similarly transformed to form second OFDM signals transmit via a second antenna over the multiple subcarriers in the same frequency band over the same time period that includes the same set of time slots. The first pilot information is transmitted via the second antenna on the second pilot subcarrier during the set of same time slots, and the second pilot information is transmitted on one of the pilot subcarriers during the same set of time slots. 1 map a first stream of input data to first complex symbols in serial format;', 'convert the first complex symbols in serial format into first complex symbols in parallel format;', 'perform an inverse Fourier transform on the first complex symbols in parallel format to form first Orthogonal Frequency Division Multiplexed (OFDM) signals associated with multiple subcarriers;', 'transmit the first OFDM signals via a first antenna over the multiple subcarriers in a same frequency band over a same time period that includes a same set of time slots;', 'transmit first pilot information via a first antenna on a first one of a plurality of pilot subcarriers during the same set of time slots;', 'transmit second pilot information via ...

Transmission method and transmission apparatus

A transmission apparatus includes processing circuitry that generates a first data sequence representing first data or a second data sequence representing second data different from the first data and selects the first data sequence as an output data sequence. A modulation scheme is determined from a plurality of modulation schemes, and the output data sequence is modulated with the determined modulation scheme. Transmission circuitry transmits the modulated output data sequence. A first time interval associated with selecting the first data sequence for the output data sequence is longer than a second time interval associated with determining the determined modulation scheme.

TRANSMISSION AND RECEPTION SIGNAL PROCESSOR AND METHOD

A transmission apparatus includes a plurality of orthogonal frequency division multiplexing (OFDM) modulation signal generators, which generate a first OFDM modulation signal and a second OFDM modulation signal. The transmission apparatus also includes a transmitter that transmits the first OFDM modulation signal from a first antenna and the second OFDM modulation signal from a second antenna, in an identical frequency band. A reception apparatus is provided, which includes a plurality of antennas that receive a plurality of OFDM modulation signals; a plurality of OFDM demodulators that transform the plurality of OFDM modulation signals to a plurality of reception signals using Fourier transform; an estimator that outputs a distortion estimation signal using one or more symbols for demodulation included in the plurality of reception signals; and a demodulator that compensates for distortion of the reception signals using the distortion estimation signal and demodulates a data symbol included in the reception signals. 1. A transmission apparatus comprising: [ inserting a first symbol for demodulation in a first plurality of subcarriers at a first time and in a second plurality of sub-carriers at a second time; and', 'inserting a symbol, having both an in-phase (I) component and a quadrature-phase (Q) component in an I-Q plane of zero, in the second plurality of sub-carriers at the first time and in the first plurality of sub-carriers at the second time;, '(i) generate a first OFDM modulation signal by, inserting a symbol, having both an in-phase (I) component and a quadrature-phase (Q) component in the I-Q plane of zero, in the first plurality of subcarriers at the first time and in the second plurality of sub-carriers at the second time; and', 'inserting a second symbol for demodulation in the second plurality of sub-carriers at the first time and in the first plurality of sub-carriers at the second time; and, '(ii) generate a second OFDM modulation signal by, ' ...

Nonlinear distortion compensating device

(57)【要約】 【課題】 無線通信システムの通信機において、直交変 調部などの線形性が低下した場合にも、送信系で発生す る非線形歪を高精度に補償する手段を提供することを目 的とする。 【解決手段】 パワー計算部１０２、直交変調部の非線 形歪補償用の第１の参照テーブル１０４、増幅器の非線 形歪補償用の第２の参照テーブル１０６、補償係数計算 部１０８、非線形歪補償部１１０を設け、送信直交ベー スバンド信号１０１の振幅値１０３により第１及び第２ の参照テーブル１０４と１０６を参照し、補償係数計算 部１０８で非線形歪補償係数１０５と１０７を合成し、 送信直交ベースバンド信号１０１と、合成で得た非線形 歪補償係数１０９との複素積を非線形歪補償部１１０で 行うことで、直交変調部１１２の線形性が確保できない 場合においても高精度な送信系の非線形歪補償を実現す ることができる。

Data transmitting apparatus, radio communication system and radio communication method

Before a secret information is transmitted, a signal transmission and reception is performed between a first radio station on the secret information transmitting side and a second radio station on the secret information receiving side, thereby estimating a radio propagation path environment shared only by the first and second radio stations. Then, the secret information is transmitted from the first radio station to the second radio station with the foregoing radio propagation path environment taken into account.

Receiving apparatus and receiving method

A receiver receives, using a plurality of antennas, a multiplexed signal that includes (i) a first OFDM modulation signal with a subcarrier carrying a symbol including multiplex information and a subcarrier carrying a pilot symbol and a subcarrier carrying a data symbol and (ii) a second OFDM modulation signal with a subcarrier carrying a symbol including multiplex information and a subcarrier carrying the pilot symbol and a subcarrier carrying the data symbol. A decoder uses the symbol including multiplex information and decodes the data symbol.

Methods and apparatus for transmitting modulation signals

A plurality of multicarrier signals is generated. Each of the plurality of multicarrier signals includes a pilot symbol sequence at a same temporal point in each multicarrier signal. Each pilot symbol sequence includes a plurality of pilot symbols with non-zero amplitude. The pilot symbol sequences are orthogonal to each other at the same temporal point. A quantity of the plurality of pilot symbols in each pilot symbol sequence is greater than or equal to a quantity of the plurality of multicarrier signals to be transmitted. The plurality of multicarrier signals are transmitted in an identical frequency band from a plurality of antennas. The plurality of antennas includes two, three, or four antennas.

Communication apparatus and communication method

Method for digital wireless communications

In a multivalue modulation type with one pilot symbol inserted for every 3 or more symbols, signal points of each one symbol immediately before and after a pilot symbol are modulated using a modulation type different from that for pilot symbols. In this way, it is possible to suppress deterioration of the accuracy in estimating the reference phase and amount of frequency offset by pilot symbols and improve the bit error rate characteristic in the signal to noise ratio in quasi-coherent detection with symbols whose symbol synchronization is not completely established.

Communication apparatus and communication system

Receiving section 102 receives security data. Propagation estimating section 103 estimates a propagation environment based on a reference signal transmitted from a communicating party. Demodulation section 104 demodulates the security data. Coding section 105 encodes information of estimated propagation environment to generate confidential information corresponding to the propagation environment. Buffer 106 temporarily stores the encoded confidential information. Decoding section 107 interprets the security data encrypted using an encryption key input from demodulation section 104, using encryption key information input frombuffer 106, to decode, and acquires the security data. It is thereby possible to ensure high security without changing the communication system greatly.