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Небесная энциклопедия

Космические корабли и станции, автоматические КА и методы их проектирования, бортовые комплексы управления, системы и средства жизнеобеспечения, особенности технологии производства ракетно-космических систем

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Мониторинг СМИ

Мониторинг СМИ и социальных сетей. Сканирование интернета, новостных сайтов, специализированных контентных площадок на базе мессенджеров. Гибкие настройки фильтров и первоначальных источников.

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Применить Всего найдено 10233. Отображено 100.

26-01-2012 дата публикации

Method for changing modulation scheme and base station apparatus using said method

Номер: US20120020281A1

Автор: Sakiko Nakamura

Принадлежит: Kyocera Corp

An EVM measurement unit measures the EVM of received signals, and performs a weighted average on them so as to derive MSE. A frequency acquiring unit acquires the change frequency of modulation scheme and the occurrence frequency of data retransmission. A moving status acquiring unit acquires the variation situation in moving velocity of a terminal apparatus or positional relationship between a base station apparatus and the terminal apparatus. A threshold modifying unit determines the modulation scheme used for the next communication, based on the value of MSE and other pieces of information described above.

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Номер записи: 1

26-01-2012 дата публикации

Distortion cancellation in radio receivers using I/Q correction

Номер: US20120020389A1

Автор: Hooman Darabi, Mohyee Mikhemar

Принадлежит: Broadcom Corp

A technique to remove second order and third order nonlinearity distortions caused by a blocker signal at an input of a radio receiver. An envelope detector is utilized at an input of the RF front-end of the receiver to obtain a magnitude of the overall signal. The output of the envelope detector is then processed at baseband to estimate coefficients that relate to the distortion. Once the coefficients are obtained, the coefficients are applied at an I/Q imbalance correction stage to also correct for the distortion by cancelling the distortion from the received signal.

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Номер записи: 2

26-01-2012 дата публикации

Electronic equalization and electronic depolarization method, receiving end equipment, and communication system

Номер: US20120020405A1

Автор: Changsong Xie, LEI Liu, Zihuan Chen

Принадлежит: Huawei Technologies Co Ltd

Embodiments of the present invention disclose an electronic equalization and electronic depolarization method, a receiving end equipment, and a communication system. According to the embodiments of the present invention, parameters required by electronic equalization and electronic depolarization are calculated by detecting a Synchronization Sequence (SS) in a received signal, and then the electronic equalization and the electronic depolarization are performed on the received signal in a frequency domain by utilizing the parameters, so as to solve a problem of the electronic equalization and the electronic depolarization in a Polarization Division Multiplexing (PDM) Orthogonal Frequency Division Multiplexing (OFDM) system. Furthermore, the realization complexity of the electronic equalization and the electronic depolarization performed in the frequency domain is greatly reduced relative to the electronic equalization and the electronic depolarization performed in a time domain.

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Номер записи: 3

02-02-2012 дата публикации

Mixed mode modulation for OFDM

Номер: US20120027119A1

Автор: Edwin H.S. Shearer

Принадлежит: Individual

In a wireless OFDM communication system such as a neighborhood area network, one or more of the following features may be used to increase throughput while accommodating worst-case channel conditions. Firstly, the cyclic prefix may be chosen to be greater than or equal to the longest delay profile that could reasonably be expected so that either demodulation method can be accommodated. Secondly, the number of pilots may be chosen to be less than that required by the worst case channel so that the data rate is maximized for a large portion of the channels in use. Thirdly, the data packet may be constructed such that the demodulation mode employed for data payload encoding is signaled in the first portion of the data packet often referred to as the PHY Header. The PHY Header is always transmitted as a coherent modulation including data and pilot tones.

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Номер записи: 4

16-02-2012 дата публикации

Method and system to detect packets of different formats

Номер: US20120039315A1

Автор: Kiran Uln, Thomas E. PARE, JR.

Принадлежит: Ralink Technology Singapore Corp Pte Ltd

A method and system in accordance with the present invention presents a new packet structure and an improved method for detecting the packet. The method and system comprise adding an additional field to the packet structure to allow for a sufficient time to process a very high throughput (VHT) signal field; and enabling the detection of the VHT signal field of the packet structure. The VHT signal field is distinguishable from other signal fields and the VHT signal field allows for a backward compatibility with other devices.

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Номер записи: 5

01-03-2012 дата публикации

Symmetrical data signal processing

Номер: US20120051412A1

Автор: Haosong Fu, HONG Liu, Raúl A. Casas

Принадлежит: ATI TECHNOLOGIES ULC

A digital communications receiver includes an input configured to receive, via a communications channel, a received first signal representing a sequence of symbols, each symbol being encoded to be representative of a plurality of data bits. A processor adjusts a magnitude and filters the received signal. An equalizer applies a cyclic prefix restoration to the adjusted and filtered signal, producing a second signal, converts the second signal from time domain to frequency domain to produce a frequency domain signal, and determines a first quantity of values representing a first portion of the symbols by evaluating a relationship of channel values representing characteristics of the communications channel and a second quantity of values representing a portion of the frequency domain signal, the first quantity being smaller than the second quantity.

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Номер записи: 6

01-03-2012 дата публикации

Communication apparatus having automatic gain control apparatus and automatic gain control method

Номер: US20120052826A1

Автор: Yanyu Chen

Принадлежит: Global Unichip Corp

The invention relates to a communication apparatus having automatic gain control apparatus and automatic gain control method. It comprises a communication apparatus with automatic gain control apparatus, a signal power calculation apparatus to calculate a first power value of the first digital signal. The operation of gain apparatus is based on the first gain value. The channel status decision apparatus decides the first channel status of the first gain value. The first digital signal has an update period of automatic gain control. The demodulator sends out the first channel impulse response to the automatic gain control apparatus. The channel status decision apparatus adjusts the update period of automatic gain control according to the first channel status of the first digital signal.

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Номер записи: 7

29-03-2012 дата публикации

Digital Television Transmitter/Receiver and Method of Processing Data in Digital Television Transmitter/Receiver

Номер: US20120076226A1

Автор: Byoung Gill Kim, Hyoung Gon Lee, In Hwan Choi, Jae Hyung Kim, Jong Moon Kim, Woo Chan Kim

Принадлежит: LG ELECTRONICS INC

A digital television (DTV) transmitter and a method of processing known data in the DTV transmitter are disclosed. The method of processing known data in a digital television (DTV) transmitter includes generating a known data sequence, trellis-encoding the known data sequence, the trellis-encoded known data sequence having upper, middle, and lower bits, wherein at least one of the upper, middle, and lower bits has an m-sequence property, and mapping the trellis-encoded known data sequence into one of 2-level, 4-level, and 8-level data sequences, wherein the mapped data sequence has substantially an m-sequence property, wherein a data sequence has an m-sequence property when a peak value among auto-correlation values of the data sequence having a length of N is 1 and all the off-peak auto-correlation values are −1/N.

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Номер записи: 8

12-04-2012 дата публикации

Channel state information transmission method appraratus and system

Номер: US20120087382A1

Автор: Gong Zhang, Pei Xiao, Xun Yang, Zihuai Lin

Принадлежит: Huawei Technologies Co Ltd

A precoding method, a precoding apparatus, a Frequency Domain Equalization (FDE) method, and an FDE apparatus are provided in the embodiments of the present invention. The precoding method includes: performing offset modulation for a transmitting signal vector; calculating a precoding matrix according to the offset-modulated transmitting signal vector and a receiver decision signal vector, where the precoding matrix is used for performing precoding for the transmitting signal vector; and performing precoding for the transmitting signal vector according to the precoding matrix. Linear precoding is performed by using the offset-modulated signal on the transmitter, and therefore, the interference caused by multiple antennas and multipath propagation is reduced, the system BER is reduced, and the complexity of implementation is low.

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Номер записи: 9

26-04-2012 дата публикации

Reception apparatus and method, demodulation apparatus and method, and program

Номер: US20120099676A1

Автор: Katsumi Takaoka, Ryo Hasegawa

Принадлежит: Sony Corp

A reception apparatus includes: a reception section configured to receive a signal modulated by one of a single-carrier scheme and a multi-carrier scheme that are specified by a predetermined standard; a single-carrier demodulation section configured to execute single-carrier demodulation based on the single-carrier scheme onto the signal; a multi-carrier demodulation section configured to execute multi-carrier demodulation based on the multi-carrier scheme onto the signal; and a demodulation control section configured to control such that one of the single-carrier demodulation and the multi-carrier demodulation is tried on the received signal in accordance with a preset predetermined rule.

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Номер записи: 10

31-05-2012 дата публикации

Apparatus and method for estimating channel in digital video broadcasting system

Номер: US20120134440A1

Автор: Alain Mourad, Hong-Sil Jeong, Ismael Gutierrez, Sung-Ryul Yun

Принадлежит: SAMSUNG ELECTRONICS CO LTD

A method of operation of a transmitting node in an Orthogonal Frequency Division Multiplexing (OFDM) communication system is provided. The method includes generating a frame including a plurality of physical layer zones, each of the plurality of physical layer zones applying different Fast Fourier Transform (FFT) sizes and different pilot patterns; and transmitting the frame.

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Номер записи: 11

28-06-2012 дата публикации

Carrier Recovery Method And Carrier Recovery Device For Pseudo Random Noise Based System

Номер: US20120163507A1

Автор: Bowel Song, YU PAN, Yuanli Wang

Принадлежит: Individual

The invention regards to Carrier recovery device, especially estimator device for carrier recovery, for pseudo random noise based systems, comprising a coarse estimator ( 13 ), a fine estimator ( 14 ), a switch ( 15 ) to select estimator output, and a sweeper ( 20 ) to sweep input data carrier frequency offset within a certain range, wherein the coarse estimator ( 13 ) is arranged to estimate a residual frequency offset by using a correlation of pseudo random noise (PN), and the fine estimator ( 14 ) is arranged to estimate the residual frequency offset by using an estimated channel information, and wherein the switch ( 15 ) is controlled to select data outputted out of the coarse estimator ( 13 ), the fine estimator ( 14 ) or the sweeper ( 20 ) as the estimator output.

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Номер записи: 12

26-07-2012 дата публикации

Parity Error Correction for Band-Limited Digital Signals

Номер: US20120192030A1

Автор: Nilesh Bhattad, Suraj Sreekanta

Принадлежит: Analog Devices Inc

An error correction method corrects and replaces erroneous digital signal samples (having N companded bits) in a receiver after ascertaining by parity check that a sample is erroneous. The method chooses M MSBs where M is less than or equal to N, and produces M test samples, each test sample being obtained by inverting a single bit from the M bits, keeping other bits unaltered. Each test sample is expanded and passed through a selected low pass filter (e.g., 15 kHz) to obtain a filtered output and a differential value between the test sample and its filtered output. The test sample producing the least differential value is chosen to replace the erroneous signal sample. The technique is applicable in NICAM demodulators receiving 14 bit sample signals (at 32 kHz) companded to (N) 10 bits from which (M) 6 MSB parity encoded bits are chosen for producing test samples.

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Номер записи: 13

02-08-2012 дата публикации

Charging and Communication System for a Battery-Powered Microstimulator

Номер: US20120197352A1

Автор: Kenneth A. McGiboney, Rafael Carbunaru, Robert D. Ozawa

Принадлежит: Boston Scientific Neuromodulation Corp

A system and method are provided for both recharging and communicating with a stimulator having a rechargeable battery, which stimulator is implanted deeply in the body, in particular where the stimulator is a microstimulator, the system includes a base station and an external device, for instance a chair pad. The chair pad may contain an antenna/charging coil and a booster coil. The antenna/charging coil can be used for charging the rechargeable battery and also for communicating with the stimulator using frequency shift keying and on-off keying. The booster coil can be used to recharge a battery depleted to zero volts. The base station connected to the chair pad may be used to power the antenna/charging coil and the booster coil.

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Номер записи: 14

13-09-2012 дата публикации

Joint preamble and code rate identifier in a mobile dtv system

Номер: US20120230437A1

Автор: Ivonete Markman, Richard W. Citta

Принадлежит: Citta Richard W, Ivonete Markman

A joint preamble and code rate identifier flag in a reserved portion of a data field synchronization segment in a digital television (DTV) data field identifies the presence of preamble training data in a forward error correction (FEC) encoded portion of the DTV data field. The identifier flag also indicates the code rate used for the data field. The data field synchronization segment is not FEC encoded, thereby allowing detection of the identifier flag without FEC decoding. The detection at a receiver of the identifier flag in a DTV data field allows receiver elements, such as an equalizer and a FEC decoder, to more readily obtain and utilize the preamble training data, thereby enhancing reception and/or simplifying receiver design.

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Номер записи: 15

20-09-2012 дата публикации

Wireless communication system, wireless communication apparatus and wireless communication method

Номер: US20120236918A1

Автор: Koji Ikuta

Принадлежит: NEC Corp

In a wireless communication system performing wireless communication via a wireless transmission path, a first wireless communication apparatus includes a receiver that receives a wireless signal via a wireless transmission path, a disconnection detector that detects disconnection of a wireless line connected to a second communication apparatus, a modulation controller that selects a modulation scheme, enabling communication under poor conditions in a transmission path, rather than a modulation scheme which has been used in wireless communication, and a transmitter that notifies the modulation scheme selected by the modulation scheme controller to the second wireless communication apparatus. The second wireless communication apparatus includes a receiver that receives the selected modulation scheme from the first wireless communication apparatus, and a transmitter that transmits signals to the first wireless communication apparatus based on the selected modulation scheme which is received by the receiver.

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Номер записи: 16

20-09-2012 дата публикации

Modulation method and radio communication system

Номер: US20120236966A1

Автор: Akihiko Matsuoka, Masayuki Orihashi, Morikazu Sagawa, Yutaka Murakami

Принадлежит: Panasonic Corp

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.

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Номер записи: 17

04-10-2012 дата публикации

Method and system for reliable cfo and sto estimation in the presence of tuner induced impairment

Номер: US20120250750A1

Автор: Gururaj Padaki, Parag Naik, S. Harish Krishnan, Saurabh Mishra, Subrahmanya Kondageri Shankaraiah

Принадлежит: Saankhya Labs Pvt Ltd

A system and method for reducing implementation complexity for estimation of a Carrier Frequency Offset (CFO) and a Symbol Timing Offset (STO) for an input signal for spectrally shaped multiple communication standards. The system is implemented by replacing multiplier with shifters. The system includes a CFO estimation block, a STO estimation block, and a band extraction block that extracts a lower band edge and an upper band edge of the input signal. The STO estimation block includes (i) a sample error generation block that computes a sampling timing error value, and (ii) a Phase Lock Loop block that estimates a frequency error and a phase error corresponding to the sampling timing error value. The CFO estimation block includes (i) a carrier offset error generation block that generates a carrier offset error value, and (ii) a leaky average block for performing a filter operation.

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Номер записи: 18

01-11-2012 дата публикации

Method and apparatus for correcting rate matching weights based on layered mapping

Номер: US20120275470A1

Автор: Senbao Guo, Yunfeng Sun

Принадлежит: ZTE Corp

The disclosure discloses a method for correcting rate matching weights based on layered mapping, includes: obtaining the number of layers to be layered mapped, determining a transmission mode for communication content; and according to the obtained number of layers and the determined transmission mode, correcting the weights for rate matching in R10. The disclosure also discloses an apparatus for correcting rate matching weights based on layered mapping, includes a weight correction unit, and a transmission mode determination unit and a layer number obtaining unit that are connected to the weight correction unit; wherein the transmission mode determination unit can determine the transmission mode for communication content and inform the weight correction unit of the transmission mode; the layer number obtaining unit can obtain the number of layers to be layered mapped and inform the weight correction unit of the number of layers; and according to the obtained number of layers and the determined transmission mode, the weight correction unit performs weights correction for rate matching. The method and the apparatus of the disclosure both can ensure that the weights for rate matching in R8 and R9 can be adaptable to the mapping manner in R10.

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Номер записи: 19

13-12-2012 дата публикации

Equalizer with Controllably Weighted Parallel High Pass and Low Pass Filters and Receiver Including Such an Equalizer

Номер: US20120314753A1

Автор: Dongyun Lee

Принадлежит: Silicon Image Inc

An adjustable equalizer that includes a first branch including a low pass filter (LPF) typically having a variable gain (β), and a second branch including a high pass filter (HPF) typically having another variable gain (α). Outputs of the branches in response to an input signal are summed to produce an equalized output. The equalizer can be implemented using CMOS technology and can be capable of equalizing an input indicative of data having a maximum data rate of at least 1 Gb/s. Typically, the equalizer is embodied in a receiver for use in equalizing a signal, indicative of video or other data, that has propagated over a serial link to the receiver.

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Номер записи: 20

27-12-2012 дата публикации

Phase Tracking in Communications Systems

Номер: US20120328064A1

Автор: Amy Gayle Hundhausen, Tommy Yu

Принадлежит: Broadcom Corp

The present invention includes a method of determining a phase estimate for an input signal having pilot symbols. The method includes receiving a plurality of pilot symbols, and then multiplying two or more pilot symbol slots by corresponding correlator coefficients to correct a phase estimate of the input signal.

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Номер записи: 21

03-01-2013 дата публикации

Method and Apparatus for Estimating a Doppler Frequency

Номер: US20130003807A1

Автор: Zhangyong Ma

Принадлежит: Telefonaktiebolaget LM Ericsson AB

A method for supporting wireless communication over a physical channel in a mobile broadband system includes providing an estimate of the channel and obtaining a channel autocorrelation function of a channel impulse response of the channel. The method also includes expressing the channel autocorrelation function as a zero order Bessel function and applying Taylor expansion to the zero order Bessel function. Additionally, the method includes performing derivation of the channel autocorrelation function to obtain an estimate of the maximum Doppler frequency and using the obtained estimate of the maximum Doppler frequency to compensate for a current Doppler effect in a receiver receiving the signals.

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Номер записи: 22

03-01-2013 дата публикации

Methods and systems for optimal zero-forcing and mmse frequency domain equalizers for complex and vsb signals

Номер: US20130003817A1

Автор: Fuyun Ling, Wanlun Zhao

Принадлежит: Qualcomm Inc

An improved receiver apparatus and algorithm for equalizing signals in a receiver device may equalize a block of data generated from N data symbols in a single carrier communication system. A first algorithm may be applied to a plurality of signal samples to generate a frequency domain representation of the samples. A channel estimate may be generated and a frequency response of a zero-forcing or a minimum-mean-square equalizer is applied. A conjugate of the computed frequency response is multiplied with a frequency domain representation for each sample to generate a product value. N-aliased frequency domain values from the generated product value may be determined for each of the samples. A second algorithm is applied to the generated N-aliased frequency domain values to generate estimates of the transmitted time domain data symbols.

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Номер записи: 23

10-01-2013 дата публикации

Wireless transmission system and wireless transmitter, wireless receiver, wireless transmission method wireless reception method and wireless communication method used with same

Номер: US20130010849A1

Автор: Junzoh Shimizu, Masahiko Ohta, Minoru Fujishima, Toshio Takada

Принадлежит: Hiroshima University NUC, Hitachi Chemical Co Ltd, Silicon Library Inc

A wireless transmission system includes a wireless HDMI transmitter and a wireless HDMI receiver. The wireless HDMI transmitter includes a carrier oscillator provided for each channel of an HDMI transmission path to output a carrier signal in a millimeter band, an OOK modulator provided for each carrier oscillator to perform on-off keying modulation on a carrier signal outputted by its corresponding carrier oscillator, and an input circuit provided for each channel of the HDMI transmission path to input a digital signal outputted by a source device to the OOK modulator. Radio signals have different planes of polarization from their adjacent channels.

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Номер записи: 24

10-01-2013 дата публикации

Radio terminal and demodulation method

Номер: US20130010905A1

Автор: Chimato KOIKE, Takashi Seyama

Принадлежит: Fujitsu Ltd

A receiving unit receives information on a modulation scheme applied to signals to a radio terminal from a transmission apparatus. An MLD unit performs maximum likelihood detection of a received signal by using a modulation scheme based on the information received by the receiving unit and a plurality of modulation schemes applicable to signals to the other radio terminals. An estimation unit estimates a modulation scheme applied to signals to the other radio terminals based on predetermined information obtained in a maximum likelihood detection process in each of the plurality of modulation schemes of the MLD unit. A controller controls the MLD unit to perform maximum likelihood detection by using the modulation scheme estimated by the estimation unit and the modulation scheme received by the receiving unit.

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Номер записи: 25

31-01-2013 дата публикации

Electrical Modulator Driver Circuit for Generating Multi-Level Drive Signals for QAM Optical Transmission

Номер: US20130027763A1

Автор: Chris Fludger, Juergen Hauenschild, Thomas Duthel

Принадлежит: Cisco Technology Inc

An apparatus and methods for generating multi-level output signals for use by an optical modulator are provided. The apparatus comprises a plurality of input signal lines each configured to receive a binary input signal, an output signal line and a plurality of amplifier stages. The amplifier stages are each connected between one of the input signal lines and the output signal line so as to each produce an output voltage on the output signal line of either a first level or a second level. The level of the output voltage is based on the binary signal at the respective input signal line, and the output voltages of the respective plurality of amplifier stages collectively produce a summed analog output voltage on the output signal line at two or more different levels each configured to drive an optical modulator.

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Номер записи: 26

21-03-2013 дата публикации

DIGITAL FREQUENCY DIVIDER

Номер: US20130070832A1

Автор: CHU Min

Принадлежит: MAXIM INTEGRATED PRODUCTS, INC.

Various embodiments of the present invention relate to systems, devices and method of frequency synthesis that generate in-phase and quadrature-phase clock signals at a programmable frequency. The generated frequency, which can range from a fraction to multiples of the input reference frequency, is generated by dividers following a phase-locked loop, thus avoiding the use of a low input reference frequency as well as frequency doubling. 1. A digital frequency divider comprises:a phase toggling unit, coupled to receive a first in-phase clock, a reset signal and a fraction-enable signal, the phase toggling unit generates a phase toggling clock that is modified from the first in-phase clock under control of the fraction-enable signal;counter, coupled to receive the phase toggling clock, the reset signal and a first multiple-bit signal, the counter counts a number of clock cycles defined by the first multiple-bit signal and generates a second multiple-bit signal;a counter reset detection block, coupled to receive the second multiple-bit signal, the counter reset detection block generates a reset signal upon the second multiple-bit signal reaching a predefined number;a half period detection block, coupled to receive the first and the second multiple-bit signals, the half period detection block generates a half period signal identifying an approximate mid-point within the number of clock cycles defined by the first multiple-bit signal; anda duty cycle equalizer, coupled to receive the reset signal and the half period signal, the first in-phase clock and a first quadrature-phase clock, the duty cycle equalizer generates an intermediate clock having the 50% duty cycle at a second frequency.2. The digital frequency divider of further comprises a divide-by-two digital frequency divider claim 1 , coupled to receive the intermediate clock claim 1 , the divide-by-two digital frequency divider generates a second in-phase clock and a second quadrature-phase clock.3. The digital ...

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Номер записи: 27

21-03-2013 дата публикации

Amplitude modulation of carrier to encode data

Номер: US20130070872A1

Автор: Nigel Iain Stuart Macrae

Принадлежит: Individual

A method and system is provided for communicating distinct data over a single frequency using on-off keying, a form of amplitude modulation, or phase changes timed to the zero crossing point of the carrier. A data signal is synchronized with the carrier by adding padding bits so that the number of bits is equal to the frequency of the carrier. The carrier is then modified by attenuating the carrier as needed once per cycle. Said carrier is then transmitted. The resulting transmitted carrier carries a number of bits equal to the transmit frequency. At the receive end, the received signal is compared to a sine wave to determine if the incoming signal is at full strength or at reduced strength, allowing for the detection of encoded digital information. In a another embodiment, the phase of the carrier is changed instead of attenuating the carrier, timed to the carrier cycles,once or twice per cycle.

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Номер записи: 28

21-03-2013 дата публикации

METHOD AND APPARATUS FOR DISTRIBUTING VIDEO UNDER MULTI-CHANNEL, AND VIDEO MANAGEMENT SYSTEM USING THE SAME

Номер: US20130074140A1

Автор: Kim Jong Wan, Lee Sang Jin

Принадлежит:

The present disclosure provides a multi-channel video distribution method and apparatus, and a video management system using the same, including a client system to communicate with a standardized video providing apparatus or a non-standardized video providing apparatus, and to receive a video/sound signal from the standardized video providing apparatus or the non-standardized video providing apparatus; a transcode system to convert the video/sound signal, received by the client system, to a video/sound format that is requested in a client application; and a server system to communicate with the client application, and to transmit, to the client application, the video/sound signal that is converted by the transcode system. 1. A multi-channel video distribution apparatus , comprising:a client system to communicate with a standardized video providing apparatus or a non-standardized video providing apparatus, and to receive a video/sound signal from the standardized video providing apparatus or the non-standardized video providing apparatus;a transcode system to convert the video/sound signal, received by the client system, to a video/sound format that is requested in a client application; anda server system to communicate with the client application, and to transmit, to the client application, the video/sound signal that is converted by the transcode system.2. The apparatus of claim 1 , wherein the client system comprises:a network video client (NVC) module to communicate with the standardized video providing apparatus; andan application programming interface (API) module to communicate with the non-standardized video providing apparatus.3. The apparatus of claim 2 , wherein the API module includes an API to receive streaming information of a non-standardized format.4. The apparatus of claim 1 , wherein the server system comprises:a network video transmitter (NVT) module to communicate with a standardized client application; anda common gateway interface (CGI) module ...

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Номер записи: 29

28-03-2013 дата публикации

Signal acquisition system

Номер: US20130077722A1

Автор: David Ho, Ka Shun Carson PUN, Siavash Ekbatani, Siukai Mak

Принадлежит: Broadcom Corp

A signal acquisition system efficiently acquires a transmitted signal even at very low power. The system may synchronize to a preamble structure in the transmitted signal and, for example, determine timing parameters that locate the preamble with respect to system timing or other clock references. The system is particularly effective at acquiring weak power signals and is also robust against significant noise and other impairments, and therefore improves the ability of a receiving device that incorporates the signal acquisition system to acquire the signal and establish communication with other devices.

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Номер записи: 30

18-04-2013 дата публикации

METHOD FOR SEAMLESSLY CHANGING POWER MODES IN AN ADSL SYSTEM

Номер: US20130094546A1

Автор: Tzannes Marcos C.

Принадлежит:

A DMT system and method with the capability to adapt the system bit rate on-line in a seamless manner. The DMT system provides a robust and fast protocol for completing this seamless rate adaptation. The DMT system also provides a framing and encoding method with reduced overhead compared to conventional DMT systems. The DMT system and method provide seamless rate adaptation with the provision of different power levels. This framing and encoding method enables a system with seamless rate adaptation capability. The system and method of the invention can be implemented in hardware, or alternatively in a combination of hardware and software. 116-. (canceled)17. In a multicarrier communication system , a method for seamlessly changing a bit rate for transmission or reception of a plurality of codewords , comprising:transmitting or receiving a message to change the bit rate from a first bit rate to a second bit rate;changing from use of a first bit allocation table corresponding to the first bit rate to use of a second bit allocation table corresponding to the second bit rate;and seamlessly transitioning to transmitting or receiving the plurality codewords at the second bit rate, wherein a fixed percentage of overhead data is maintained before and after the transition.18. The method of claim 17 , wherein the plurality of codewords maintains a same specified codeword size claim 17 , a same specified number of parity bits for forward error correction claim 17 , and a same specified interleaving parameter before and after the transition.19. The method of claim 17 , wherein a size of a codeword in the plurality of codewords is aligned with a size of an ADSL frame.20. The method of claim 17 , further comprising receiving the second bit allocation table from a transceiver prior to transitioning to transmitting or receiving the plurality codewords at the second bit rate.21. The method of claim 17 , further comprising transmitting the second bit allocation table to a transceiver ...

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Номер записи: 31

25-04-2013 дата публикации

COMMUNICATION SYSTEM, COMMUNICATION APPARATUS, AND COMMUNICATION METHOD

Номер: US20130100914A1

Автор: Goto Jungo, Hamaguchi Yasuhiro, Nakamura Osamu, Takahashi Hiroki, Yokomakura Kazunari

Принадлежит: SHARP KABUSHIKI KAISHA

There are included a plurality of mapping units to which a plurality of data signal sequences related to the same data signal sequence are input via spectra cyclic shift units and which arrange the input data signal sequences on the frequency axis and output the arranged data signal sequences as transmission frequency spectra; an assignment information acquisition unit that controls the plurality of mapping units based on assignment information to cause the data signal sequences arranged on the frequency axis to partially overlap; the spectra cyclic shift units shifting, under control of an amount-of-shift decision unit, the input data signal sequences by an amount of cyclic shift to cause partially overlapping data signals to be identical and outputting the data signal sequences; and a plurality of transmit antennas that send out the transmission frequency spectra output by the plurality of mapping units. 1. A communication apparatus comprising:a plurality of mapping units to which a plurality of data signal sequences related to the same data signal sequence are input and which arrange the input data signal sequences on the frequency axis and output the arranged data signal sequences as transmission frequency spectra, at least one of the plurality of data signal sequences being input via a spectra cyclic shift unit;an assignment information acquisition unit that controls the plurality of mapping units based on assignment information to cause the data signal sequences arranged on the frequency axis to partially overlap;an amount-of-cyclic-shift decision unit that decides an amount of cyclic shift based on control of the assignment information acquisition unit;the spectra cyclic shift unit shifting, under control of the amount-of-cyclic-shift decision unit, the at least one input data signal sequence by the amount of cyclic shift to cause partially overlapping data signals to be identical and outputting the at least one data signal sequence; anda plurality of ...

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Номер записи: 32

25-04-2013 дата публикации

MODEM DEVICE AND AMPLITUDE ADJUSTMENT METHOD

Номер: US20130101001A1

Автор: Teramoto Taro

Принадлежит: NEC Corporation

A modem device includes a modulation unit that generates a modulated signal, a frequency conversion unit that generates an intermediate frequency signal from an external input signal, and a demodulation unit that demodulates the modulated or intermediate frequency signal and generates a reception signal. In a communication mode, the modulation unit outputs the modulated signal to a external device , the frequency conversion unit generates the intermediate frequency signal, and the demodulation unit demodulates the intermediate frequency signal and generates the reception signal. In an adjustment mode, the modulation unit outputs the modulated signal to the demodulation unit , and the demodulation unit generates the reception signal from the modulated signal and adjusts an amplitude of the transmission signal based on the reception signal. 1. A modem device comprising:a modulation unit that modulates a transmission signal and generates a modulated signal;a frequency conversion unit that converts a frequency of an external input signal and generates an intermediate frequency signal, the external input signal being input from an external device;a demodulation unit that demodulates the modulated signal or the intermediate frequency signal and generates a reception signal; andan adjustment unit that adjusts amplitude of the transmission signal based on the reception signal, wherein the modulation unit outputs a first modulated signal to the external device, the first modulated signal being generated using the first frequency set at the time of output to the external device,', 'the frequency conversion unit converts a second frequency set to the external input signal into the intermediate frequency signal with a third frequency, and', 'the demodulation unit demodulates the intermediate frequency signal and generates a first reception signal, and, 'in a communication mode for communicating with the external device,'} the modulation unit outputs a second modulated signal ...

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Номер записи: 33

25-04-2013 дата публикации

METHOD AND APPARATUS FOR JOINT DECODING AND EQUALIZATION

Номер: US20130101010A1

Автор: Biracree Stephen Leonard, Casas Raul Alejandro, Endres Thomas Joseph, Shah Anand Mahendra, Simovich Slobodan

Принадлежит:

The current application is directed to joint decoding and equalization using a decision feedback equalizer. An example method to which the current application and certain of the current claims are directed uses joint trellis decoding and decision feedback equalization to efficiently estimate non-contiguous symbols using non-contiguous equalizer outputs. The estimation process uses all new possibilities of symbol values, rather than old decision feedback symbol estimates. 1. A method carried out by a communications receiver having a decision feedback equalizer , the method comprising:receiving, by the decision feedback equalizer, a first sequence of processed symbols;processing the first sequence of processed symbols by carrying out a symbol-estimation operation for each symbol of the received first sequence of processed symbols, the symbol-estimation operation estimating, for a currently-considered symbol, a corresponding processed symbol as well as a processed-symbol value for at least one additional symbol of the timed and data-synchronized signal; andoutputting a second sequence of processed symbols corresponding to the first sequence of processed symbols.2. The method of wherein the corresponding at least one additional symbol corresponds to a symbol that is not adjacent claim 1 , in the sequence of symbols claim 1 , to the currently-considered symbol.3. The method of further including estimating claim 1 , for a currently-considered symbol claim 1 , a corresponding processed symbol by considering all possible symbols claim 1 , under the channel-coding constraint claim 1 , and selecting a symbol with greatest likelihood to correspond to the currently-considered symbol in an original sequence of symbols transmitted to the communications receiver and suffering echo distortion during transmission.4. The method of wherein the symbol-estimation operation includes:receiving first sequence of processed symbols;receiving a programmable input delay;receiving an indication ...

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Номер записи: 34

25-04-2013 дата публикации

Sub-Band Power Scaling Reporting and Sub-Band Transmit Power Estimation

Номер: US20130101055A1

Автор: Anand Dabak, Il Han Kim, Kumaran Vijayasankar, Ramanuja Venantham, Tarkesh Pande

Принадлежит: Texas Instruments Inc

Systems and methods for routing protocols for power line communications (PLC) are described. In some embodiments, a method performed by a PLC device, such as a PLC meter, may include selecting one or more transmit sub-bands on which to transmit frames, where the transmit sub-bands comprise groups of six carrier frequencies. The PLC device then generates a frame comprising a tone map that indicates which transmit sub-bands are used to carry data for the frame. The tone map using two bits per transmit sub-band to indicate a status of each transmit sub-band. The PLC device then transmits the frame on the selected transmit sub-bands using OFDM. A resolution bit and a mode bit may be used to provide additional information about the transmit sub-bands, such as an amount of power adjustment that has been applied to carrier frequencies and whether dummy bits are transmitted on unused carrier frequencies.

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Номер записи: 35

02-05-2013 дата публикации

CONSTELLATION DETECTION IN A MULTI-MODE QAM COMMUNICATIONS SYSTEM

Номер: US20130107922A1

Автор: FIMOFF Mark, TOMEZAK Greg

Принадлежит: INTERSIL AMERICAS INC.

Systems and methods for determining an unknown QPSK or QAM constellation from a set of possible received constellations are described. One method utilizes a histogram of the power of the signal after inter-symbol-interference has been minimized with a modified constant modulus algorithm equalizer. The constellation may be determined before carrier frequency and phase has been fully recovered. An unknown QPSK or QAM constellation may be identified before or after equalization using disclosed methods for analyzing an output power histogram. 1. An apparatus comprising a modem configured to:detect a plurality of synchronization signals; and extract mode information from a frame of data corresponding to the one synchronization signal;', 'determine a current constellation by identifying one of a plurality of valid constellation code words that most closely matches a received code word corresponding to the mode information; and', 'update a confidence metric associated with a previously identified constellation by increasing the confidence metric if the current constellation matches the previously identified constellation, and decrease the confidence metric if the current constellation is different from the previously identified constellation,, 'responsive to detecting one of the plurality of synchronization signalswherein the modem is further configured to decode the frame of data using the previously identified constellation if the confidence metric exceeds a predetermined threshold.2. The apparatus of claim 1 , wherein the modem is configured to determine a current constellation using cross-correlations performed for each of the plurality of valid constellation code words with the received code word.3. The apparatus of claim 1 , wherein the frame of data is one of a plurality of frames received in an unequalized signal received by the modem.4. The apparatus of claim 3 , wherein the modem is configured to determine the current constellation while recovering a carrier from ...

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Номер записи: 36

02-05-2013 дата публикации

Phase detection in digital communication receivers

Номер: US20130107992A1

Автор: Bernard Arambepola, Parveen K. Shukla, Sahan S. Gamage, Thushara Hewavithana

Принадлежит: Intel Corp

According to various embodiments, apparatus and methods disclosed herein include computing phase error of a received signal based on an estimate of a first component (e.g., in-phase component) of a transmitted signal and an analytic representation of the estimate of the first component of the transmitted signal. The analytic representation of the estimate of the first component of the transmitted signal may represent an estimate of a second component (e.g., quadrature phase component) of the transmitted signal. The analytic representation of the estimated first component may be computed using at least one of a Hilbert transform or Fourier transform on the estimated first component of the transmitted signal.

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Номер записи: 37

09-05-2013 дата публикации

METHOD AND APPARATUS FOR PERFORMING CHANNEL SHORTENING EQUALIZATION WITH FREQUENCY NOTCH MITIGATION

Номер: US20130114664A1

Автор: CHEN Yen-Liang, Feng Shao-Wei, WU An-Yeu, Zhan Cheng-Zhou

Принадлежит:

A method for performing channel shortening equalization with frequency notch mitigation is provided, where the method is applied to an electronic device. The method includes: obtaining channel response information from channel estimation to determine a relaxed channel convolution matrix corresponding to the channel response information, with the relaxed channel convolution matrix being a partial matrix of a channel convolution matrix corresponding to the channel response information, wherein the relaxed channel convolution matrix is obtained from omitting a portion of matrix elements of the channel convolution matrix; and based upon the relaxed channel convolution matrix, jointly performing time domain channel shortening control and frequency domain flatness control over the TEQ to perform channel shortening equalization with frequency notch mitigation by utilizing the TEQ. In particular, the portion of matrix elements includes a plurality of rows of matrix elements within the channel convolution matrix. An associated apparatus is also provided. 1. A method for performing channel shortening equalization with frequency notch mitigation , the method being applied to an electronic device , the electronic device comprising a time domain equalizer (TEQ) , the method comprising the steps of:obtaining channel response information from channel estimation to determine a relaxed channel convolution matrix corresponding to the channel response information, with the relaxed channel convolution matrix being a partial matrix of a channel convolution matrix corresponding to the channel response information, wherein the relaxed channel convolution matrix is obtained from omitting a portion of matrix elements of the channel convolution matrix; andbased upon the relaxed channel convolution matrix, jointly performing time domain channel shortening control and frequency domain flatness control over the TEQ to perform channel shortening equalization with frequency notch mitigation by ...

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Номер записи: 38

09-05-2013 дата публикации

WIRELESS COMMUNICATIONS DEVICE AND METHOD

Номер: US20130114749A1

Автор: EJIMA Satoru, Kobayashi Takehiko, YAMAMOTO Keisuke

Принадлежит: HITACHI KOKUSAI ELECTRIC INC.

A wireless communications device and method carries out a process including estimating channel information based on a received signal; generating pseudo-transmission signal point candidates based on the channel information and/or transmission signal point candidates; and generating a replica of the received signal based on the pseudo-transmission signal point candidates and the estimated channel information. The process further includes performing matrix operations on the basis of the received signal and the replica thereof; selecting pseudo-transmission signal point candidates which have a greater effect on likelihood calculations; reverting the selected pseudo-transmission signal point candidates to original transmission signal point candidates and calculating final likelihoods; and restoring the received signal on the basis of the calculated likelihoods. 1. A wireless communication device comprising:an estimation unit which estimates channel information from on a receiving signal received through an antenna;a candidate generation unit which generates pseudo-transmission signal point candidates based on at least one of the channel information and original transmission signal point candidates;a replica generation unit which generates a receiving signal replica based on the pseudo-transmission signal point candidates and the channel information;a metric computation unit which performs metric computation based on the generated receiving signal replica and the receiving signal to select the pseudo-transmission signal point candidates having a greater effect on calculation of likelihoods;a likelihood computation unit which reverts the selected pseudo-transmission signal point candidates to the original transmission signal point candidates to calculate final likelihoods; anda restoration unit which restores the receiving signal based on the calculated likelihoods.2. The wireless communication device of claim 1 , wherein each of the pseudo-transmission signal point ...

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Номер записи: 39

09-05-2013 дата публикации

SYSTEM AND METHOD OF ENCODING AND TRANSMITTING CODEWORDS

Номер: US20130114759A1

Автор: AHMED Ebad, Blankenship Yufei Wu, BONTU Chandra Sekhar, Buckley Michael Eoin, Periyalwar Shalini Suresh, Xin Yan

Принадлежит: RESEARCH IN MOTION LIMITED

Systems and methods are provided for encoding and transmitting codewords. A message is encoded in two encoders. For at least one of the two encoders, the message is algebraically modified prior to being encoded. In a specific example, the message is algebraically modified prior to being encoded in each of two traditionally non-systematic encoders, with the result that the output is equivalent to that of a turbo encoder. 1. A method comprising:performing a first encoding of a first message to produce a first codeword where the first message is related to and has the same length as an original message;generating a second message by at least algebraically modifying a third message, the second message having the same length as the original message, and the third message is related to and has the same length as the original message;performing a second encoding of the second message to produce a second codeword; andtransmitting at least part of the first codeword and transmitting at least part of the second codeword.2. The method of wherein the third message is the original message.3. The method of wherein:generating the second message comprises interleaving the original message to produce the third message.4. The method of wherein:performing a first encoding comprises using a non-recursive convolutional encoder; andperforming a second encoding comprises using a non-recursive convolutional encoder.5. The method of wherein:generating the second message and performing the second encoding of the second message to produce a second codeword are performed such that the second codeword is the same as what would have been obtained by encoding the third message with a recursive systematic code.6. The method of further comprising:generating the first message by at least performing algebraically modifying a fourth message, wherein the fourth message has the same length as the original message.7. The method of wherein the fourth message is the original message.8. The method of ...

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Номер записи: 40

16-05-2013 дата публикации

FEEDER LINK CONFIGURATIONS TO SUPPORT LAYERED MODULATION FOR DIGITAL SIGNALS

Номер: US20130121430A1

Автор: Anderson Paul R., Chen Ernest C., Santoru Joseph

Принадлежит: THE DIRECTV GROUP, INC.

Systems and methods are disclosed for feeder link configurations to layered modulation. One feeder link system employs feeder link spot beam to antennas in distinct coverage areas to enable frequency reuse. Another system employs narrow beam width feeder link antenna to illuminate individual satellites also enabling frequency reuse. Yet another system uses layered modulation in the feeder link. Another feeder link system employs a higher order synchronous modulation for the satellite feeder link than is used in the layered modulation downlink signals. 130-. (canceled)31. A The system of claim 61 , wherein:the feeder link signal comprises a layered modulation feeder link signal including an upper layer feeder link signal and a lower layer feeder link signal;the demodulator comprises a layered modulation demodulator;the first modulator modulates the upper layer feeder link signal to produce the modulated upper layer signal of the layered modulation downlink signal; andthe second modulator modulates the lower layer feeder link signal to produce the modulated lower layer signal of the layered modulation downlink signal.32. The system of claim 31 , wherein the upper layer feeder link signal and the lower layer feed link signal are transmitted from a common location.33. The system of claim 31 , wherein the upper layer feeder link signal and the lower layer feed link signal are each transmitted from a different location.34. The system of claim 31 , wherein a first frequency bandwidth of the upper layer downlink signal partially overlaps a second frequency bandwidth of the lower layer downlink signal.35. The system of claim 31 , wherein a first frequency bandwidth of the upper layer downlink signal completely overlaps a second frequency bandwidth of the lower layer downlink signal.36. The system of claim 31 , wherein the upper layer feeder link signal and the lower layer feeder link signal are coherently transmitted to the layered modulation receiver/demodulator.37. The ...

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Номер записи: 41

16-05-2013 дата публикации

RADIO RECEIVER APPARATUS AND RADIO TRANSMITTER APPARATUS

Номер: US20130121445A1

Автор: Aramaki Takashi, Futagi Sadaki, Hiramatsu Katsuhiko, Imamura Daichi, Iwai Takashi, Miyoshi Kenichi, Nishio Akihiko

Принадлежит: Panasonic Corporation

A radio receiver apparatus that can effectively utilize GI to improve the reception quality. In this apparatus, a data extracting part extracts a data portion of a direct wave from a signal subjected to a radio reception process by a received RF part. A GI extracting part extracts, from the signal subjected to the radio reception process by the received RF part, GI having a length determined by an extracted GI length deciding part. The extracted GI is adjusted by a data position adjusting part such that its rear end coincides with the read end of the extracted data portion. A combining part combines the extracted data portion with the GI the data position of which has been adjusted. The combined signal is then supplied to a frequency axis equalizing part, which equalizes the signal distortions of the combined signal on the frequency axis. 1. A radio receiving apparatus that is configured to receive , in a single carrier transmission system , a plurality of data symbols that are included in a data part and arranged between a front end and a rear end of the data part , the radio receiving apparatus comprising:a receiving section that is configured to receive, during a cyclic prefix period, one or more data symbols including data that is the same as data included in a portion of the plurality of data symbols which are arranged to map at least one data symbol including ACK/NACK information from the rear end of the data part, the portion ranging from the rear end of the data part and corresponding to the cyclic prefix period to thereby contain said at least one data symbol including ACK/NACK information, the receiving section being further configured to receive the plurality of data symbols in the data part after the cyclic prefix period;to thereby receive, during the cyclic prefix period, said one or more data symbols including data that is the same as data included in the portion containing said at least one data symbol including ACK/NACK information, and to receive, ...

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Номер записи: 42

30-05-2013 дата публикации

TRANSMITTER CONTROL IN COMMUNICATION SYSTEMS

Номер: US20130136161A1

Автор: Mezer Amir, Ran Adee

Принадлежит:

Techniques are described to adaptively adjust the equalizer settings of each transmitter in a transmitter-receiver pair. The transmitter-receiver pair can be used at least with implementations that comply with 40GBASE-CR4 or 100GBASE-CR10. For implementations that comply with 40GBASE-CR4, equalizer settings of four transmitters may be independently established. 1. A method comprising:receiving a first signal from a first lane;determining first equalizer settings of a first transmitter of the first signal based in part on error properties of the first signal using clock and data recovery for the first signal and also based in part on control signals from the first transmitter determined using a first control channel decoder, wherein the first equalizer used by the first transmitter is in compliance with one or more of clauses 72.7.1.10 and 72.7.1.11 of IEEE Std 802.3ap-2007;requesting adjustment of the first equalizer settings using a control channel in compliance with a 10GBASE-KR PMD control function defined in clause 72.6.10 of IEEE Std 802.3ap-2007;receiving a second signal from a second lane;determining second equalizer settings of a second transmitter of the second signal based in part on error properties of the second signal using clock and data recovery for the second signal and also based in part on control signals from the second transmitter determined using a control channel decoder;transmitting the first equalizer settings to a receiver associated with the first transmitter;transmitting the second equalizer settings to a receiver associated with the second transmitter;requesting to adjust settings applied by the first equalizer of the first transmitter;requesting to adjust settings applied by the second equalizer of the second transmitter; and the first equalizer settings are determined independently from the second equalizer settings;', 'the first transmitter transmits independently of the second transmitter;', 'an aggregate transmission rate of signals ...

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Номер записи: 43

13-06-2013 дата публикации

ADAPTIVE RECEIVER SYSTEM AND ADAPTIVE TRANSCEIVER SYSTEM

Номер: US20130148704A1

Автор: ARIMA Yukio, SHINMYO Akinori

Принадлежит: Panasonic Corporation

A phase comparison circuit outputs a first phase comparison signal indicating whether or not an edge of an equalization signal is in a first interval between sampling timing and timing having a first predetermined phase advance, and outputs a second phase comparison signal indicating whether or not the edge of the equalization signal is in a second interval between the sampling timing and timing having a second predetermined phase delay. A determination circuit compares a predetermined comparison target pattern with output patterns of the first and second phase comparison signals corresponding to each bit of a detection data pattern. 1. An adaptive receiver system for receiving a reception signal , comprising:an equalizer circuit configured to equalize the reception signal based on a strength adjustment signal representing an equalization strength and output the reception signal after equalization as an equalization signal; a first phase comparator to which a sampling clock and a first clock having a first predetermined phase advance with respect to the sampling clock and which outputs a first phase comparison signal indicating whether or not an edge of the equalization signal is in a first interval between sampling timing of the sampling clock and sampling timing of the first clock, and', 'a second phase comparator to which the sampling clock and a second clock having a second predetermined phase delay with respect to the sampling clock and which outputs a second phase comparison signal indicating whether or not the edge of the equalization signal is in a second interval between the sampling timing of the sampling clock and sampling timing of the second clock;, 'a phase comparison circuit including'}a clock adjustment circuit configured to adjust, based on the first and second phase comparison signals, a phase of the sampling clock such that a phase of the equalization signal and the phase of the sampling clock are coincidence with each other and output the ...

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Номер записи: 44

13-06-2013 дата публикации

SYSTEM AND METHOD FOR COMMUNICATING USING AN IN-VEHICLE SYSTEM

Номер: US20130148705A1

Автор: Furbeck David S., JANHUNEN Stefan E., Simmons Sean

Принадлежит:

A system and method for communicating wirelessly from a mobile device to a remote receiver station is disclosed. The system includes a controller configured to monitor a status of the mobile device and, upon an initiation event, initiate a data transfer process to wirelessly communicate data to the remote receiver station. The system also includes a voice-band modem that, upon initiation of the data transfer process. The voice-band modem is configured to receive data for transfer to the remote receiver station, encode the data to form a series of encoded packets, and transmit the encoded packets to the remote receiver station using a first modulation scheme. Thereafter, unless an indication that the series of packets has been received by at the receiving station is provided, the voice-band modem automatically retransmit the encoded packets to the remote receiver station using a second modulation scheme. 120-. (canceled)21. An answering point device for communicating with a mobile device , the answering point device configured to:receive a series of symbols from the mobile device, each symbol being a sum of k orthogonal sinusoids out of a set of n orthogonal sinusoids, where k and n are integers with k Подробнее

Номер записи: 45

13-06-2013 дата публикации

Soft linear and non-linear interference cancellation

Номер: US20130148711A1

Автор: Divaydeep Sikri, Farrokh Abrishamkar, Ken Delgado

Принадлежит: Qualcomm Inc

A two stage interference cancellation (IC) process includes a linear IC stage that suppresses co-channel interference (CCI) and adjacent channel interference (ACI). The linear IC stage disambiguates otherwise super-trellis data for non-linear cancellation. Soft linear IC processing is driven by a-posteriori probability (Apop) information. A second stage performs expectation maximization/Baum Welch (EM-BW) processing that reduces residual ISI left over from the first stage and also generates the Apop which drives the soft linear IC in an iterative manner.

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Номер записи: 46

13-06-2013 дата публикации

System and method for ask ofdm transmission and reception

Номер: US20130148764A1

Автор: Shouxing Qu

Принадлежит: Research in Motion Ltd

An OFDM system and method using amplitude shift keying (ASK) for subcarrier modulation is provided. Because ASK is used, the signal of each symbol in time domain is conjugate-symmetric. In addition, among the discrete numbers of each symbol, two of them are always real. These properties are utilized such that only half of the numbers of each symbol sequence are transmitted. The generated baseband signal can be a complex or a real signal. As a result, the bandwidth efficiency of the derived ASK-OFDM is the same as that of QAM-OFDM.

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Номер записи: 47

20-06-2013 дата публикации

METHODS AND APPARATUS FOR DETECTING AND DECODING ADAPTIVE EQUALIZATION TRAINING FRAMES

Номер: US20130156086A1

Автор: Ahmed Yasser, Dai Xingdong, Mobin Mohammad S., Smith Lane A.

Принадлежит: Agere Systems LLC

Methods and apparatus are provided for detecting and decoding adaptive equalization training frames (having a frame marker comprised of a string of binary ones and binary zeroes). Training frames are detected by shifting the received data; inserting at least one binary value at one end of the shifted received data to generate a modified version of the received data; applying a logic function to the received data and the modified version of the received data that identifies when corresponding bit positions have different values; and detecting the frame marker when an output of the logic function has a first binary value in an approximate middle of a string of a second binary value. The training frames are decoded using a distance between the approximate center of the frame marker and a predefined binary value in an output of the logic function. 1. A method for decoding a received training frame having a frame marker and encoded using a Differential Manchester Encoding technique , comprising:detecting an approximate center of said frame marker;shifting said received data by one or more bit positions;inserting at least one predefined binary value at one end of said shifted received data to generate a modified version of said received data;applying a logic function to said received data and said modified version of said received data, wherein said logic function identifies when corresponding bit positions in said received data and said modified version of said received data have different values; anddecoding at least a portion of said received training frame using a distance between said approximate center of said frame marker and a predefined binary value in an output of said logic function.2. The method of claim 1 , wherein said decoded portions comprise one or more of a coefficient update field and a status report field.3. The method of claim 1 , wherein said predefined binary value in said output of said logic function corresponds to a transition in said received ...

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Номер записи: 48

27-06-2013 дата публикации

CIRCUIT FOR TRANSMITTING ASK RF SIGNALS WITH DATA SIGNAL EDGE ADAPTATION

Номер: US20130163697A1

Автор: MOSER Michel

Принадлежит: EM MICROELECTRONIC-MARIN SA

The circuit is provided for the transmission of data amplitude modulated radio frequency signals. The circuit includes a local oscillator for generating an oscillating signal at a determined carrier frequency, a unit for shaping data pulses to supply a data amplitude modulation control signal (Vmod), and a power amplifier receiving the oscillating signal and the data amplitude modulation control signal (Vmod) for the transmission of data amplitude modulated radio frequency signals by an antenna or an antenna arrangement. The data pulse shaping unit () includes a pulse shaper () for digitally adapting the data transition edges on the basis of an incoming digital data signal (d), and a digital-analogue conversion stage () for converting a digital data signal shaped in the unit, in order to supply the data amplitude modulation control signal (Vmod) to the power amplifier. 1. A data amplitude modulation circuit for the transmission of radio frequency signals , the circuit including:a local oscillator for generating an oscillating signal at a determined carrier frequency,a unit for shaping data pulses to supply a data amplitude modulation control signal, anda power amplifier receiving the oscillating signal from the local oscillator and the data amplitude modulation control signal from the data pulse shaping unit, for the transmission of data amplitude modulated radio frequency signals by an antenna or an antenna arrangement,wherein the data pulse shaping unit includes a pulse shaper for digitally adapting the data transition edges on the basis of an incoming digital data signal, and a digital-analogue conversion stage for converting a digital data signal shaped in the unit, so as to supply the data amplitude modulation control signal to the power amplifier.2. The circuit according to claim 1 , wherein the pulse shaper includes several wave shapes stored in a memory claim 1 , wherein each wave shape can be individually selected to digitally attenuate or smooth all the ...

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Номер записи: 49

04-07-2013 дата публикации

EQUALIZER RECEIVER AND OPERATING METHOD THEREOF IN WIRELESS COMMUNICATION SYSTEM

Номер: US20130170538A1

Автор: KI Young-Min, KONG Se-Jin, LEE Kyung-Ha, SONG Seong-Wook

Принадлежит: SAMSUNG ELECTRONICS CO. LTD.

An equalizer-based receiver and an operating method thereof in a wireless communication system are provided. The equalizer-based receiver includes a reception multi-path detector, a controller, and an equalize receiver. The reception multi-path detector groups reception signals according to a predetermined reference to classify the reception signals into a plurality of delay clusters, and estimates a position of the plurality of delay clusters. The controller determines whether the plurality of delay clusters exist within a predetermined threshold range based on a result of the estimated position, and controls an operation mode of the equalizer-based receiver depending on a result of the determination. The equalize receiver performs one of a mode for removing an interference between the plurality of delay clusters and a mode for applying a diversity technique to a delay cluster under control of the controller. 1. An apparatus of an equalizer-based receiver in a wireless communication system , the apparatus comprising:a reception multi-path detector for grouping reception signals according to a predetermined reference to classify the reception signals into a plurality of delay clusters, and for estimating a position of the plurality of delay clusters;a controller for determining whether the plurality of delay clusters exist within a predetermined threshold range based on a result of the estimated position, and for controlling an operation mode of the equalizer-based receiver depending on a result of the determination; andan equalize receiver for performing one of a mode for removing an interference between the plurality of delay clusters and a mode for applying a diversity technique to a delay cluster under control of the controller.2. The apparatus of claim 1 , wherein claim 1 , when the plurality of delay clusters do not exist within the predetermined threshold range claim 1 , the equalize receiver removes an interference between the plurality of delay clusters ...

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Номер записи: 50

04-07-2013 дата публикации

Multimode transmitter apparatus

Номер: US20130170577A1

Автор: Akihiko Matsuoka

Принадлежит: Panasonic Corp

Provided is a multimode transmitter apparatus that, in a case of using different paths to process modulated signals, can suppress the signal overlapping or loss that would occur during a path switching. In the apparatus, a baseband modulating unit ( 110 ), which supports a plurality of modulation schemes using different modulation bandwidths, outputs either first modulated signals or second modulated signals. An LPF ( 130 - 1 ) and an LPF ( 130 - 2 ), which have delay amounts Δtd 1 and Δtd 2 , perform signal processings of the first and second modulated signals, respectively. A timing control unit ( 160 ) sets the modulation schemes and the switching timings of the modulation schemes. The timing control unit ( 160 ) sets, on the basis of the switching timings and the delay amounts Δtd 1 and Δtd 2 , the switching timings of a modulated signal selecting switch ( 120 ) and a signal processing delay adjusting switch ( 140 ) to be different from each other.

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Номер записи: 51

18-07-2013 дата публикации

Frequency domain interference cancellation and equalization for downlink cellular systems

Номер: US20130184019A1

Автор: Raheel Khan, Steve H. Hsu

Принадлежит: Qualcomm Inc

Methods and apparatus are described for interference cancellation of interference components of a time domain signal in the frequency domain. A communications device receives a time domain sequence and generates overlapping time domain segments from the time domain sequence. The overlapping time domain segments are then converted to the frequency domain to generate frequency domain representations of the overlapping time domain segments. The frequency domain representations are stored in a residual memory, and interference components are directly removed from the frequency domain representations stored in the residual memory in the frequency domain.

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Номер записи: 52

25-07-2013 дата публикации

Code Channel Detecting Method and Related Device and Communication System

Номер: US20130188669A1

Автор: Guan Wenkang, Guo Jing, Li Feng, ZHANG Chunling

Принадлежит: Huawei Technologies Co., Ltd.

Embodiments of the present invention disclose a code channel detecting method and a related device and a communication system. In the solutions provided by the embodiments of the present invention, whether a DPA code channel is in an active state is determined with multiple thresholds based on a first reference value and a third reference value, or based on a first reference value, a second reference value and a third reference value. This mechanism takes multiple possible false determination situations into consideration, thereby ensuring a code channel correct detection rate in multiple interference scenarios and relatively reducing a false alarm rate. 1. A code channel detecting method , comprising:equalizing a received signal to obtain an equalized signal;descrambling and despreading the equalized signal using a spreading code sequence corresponding to each downlink packet access DPA code channel, and performing energy accumulation on a symbol that is corresponding to the each DPA code channel and is acquired after the descrambling and despreading, to obtain a symbol energy accumulated value corresponding to the each DPA code channel; andif the symbol energy accumulated value corresponding to a DPA code channel satisfies an active code channel determination condition, indicating the DPA code channel as an active code channel, whereinthe active code channel determination condition comprises that:the symbol energy accumulated value corresponding to the DPA code channel is greater than a first reference value and greater than a third reference value; orthe symbol energy accumulated value corresponding to the DPA code channel is greater than a first reference value and greater than a third reference value, and at least one of symbol energy accumulated values corresponding to DPA code channels is greater than a second reference value, wherein the first reference value is determined based on a first threshold and estimated in-band noises, and the in-band noises are ...

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Номер записи: 53

01-08-2013 дата публикации

System and Method for Non-Interleaved Signal Field

Номер: US20130195167A1

Автор: Aboul-Magd Osama, Au Kwok Shum, Suh Junghoon, WU Tianyu

Принадлежит: Futurewei Technologies, Inc.

Efficient decoding in IEEE 802.11ah networks can be achieved by transmitting the signal (SIG) preamble field without interleaving bits within the SIG field. This may allow channel equalization and decoding steps to be performed contemporaneously upon reception of the frame, which allows for the implementation of non-linear channel equalization techniques (e.g., maximum likelihood (ML) equalization, etc. 1. A method of transmitting a wireless signal , the method comprising:encoding data into a signal (SIG) field to obtain an encoded SIG field; andtransmitting the encoded SIG field without interleaving bits within the encoded SIG field.2. The method of claim 1 , further comprising:encoding data into a long training field (LTF) to obtain an encoded LTF; andtransmitting the encoded LTF without interleaving bits within the encoded LTF, wherein the encoded SIG field and the encoded LTF are communicated within a preamble of a frame.3. The method of claim 2 , wherein the frame is an Institute of Electrical and Electronics Engineers (IEEE) 802.11ac frame.4. The method of claim 2 , wherein transmitting the encoded SIG field without interleaving bits within the encoded SIG field allows a receiver to perform equalization while decoding the frame.5. The method of claim 2 , wherein transmitting the encoded SIG field without interleaving bits within the encoded SIG field allows a receiver to perform non-linear equalization on the frame.6. A transmitter comprising:a processor; and encode data into a signal (SIG) field to obtain an encoded SIG field; and', 'transmit the encoded SIG field without interleaving bits within the encoded SIG field., 'a computer readable storage medium storing programming for execution by the processor, the programming including instructions to7. The transmitter of claim 6 , wherein the programming further includes instructions to:encode data into a long training field (LTF) to obtain an encoded LTF; andtransmit the encoded LTF without interleaving bits ...

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Номер записи: 54

01-08-2013 дата публикации

AUTOMATIC GAIN CONTROL

Номер: US20130195231A1

Автор: Hearne Peter, Khandelwal Pulkit, Simpson Richard

Принадлежит: TEXAS INSTRUMENTS INCORPORATED

The present invention relates to receiver circuitry and methods for the reception of serial data and in particular to the setting of a gain within such circuitry so that the data may be successfully received. It provides a data receiver that comprises an amplifier connected to receive a data waveform and to amplify it, the amplifier having a controllable gain, a test sampler connected to sample the amplified data waveform to a 1 or 0 based on a reference level, to provide a set of test bits and a gain adjusting circuit responsive to the number of test bits that are one of 1 or 0 in the set of the test bits. 1. A method performed in a data receiver for a data waveform of adjusting the gain applied to the data waveform by an amplifier , comprising:providing a reference level,sampling a set of test bits from the amplified waveform with respect to the reference level,adjusting the level of the gain applied by the amplifier in response to the number of test bits in the set that have a first binary value.2. A method as claimed in wherein the sampling and adjusting is repeated.3. A method as claimed in wherein the reference level is a target level for a data waveform trace for a particular data code in the data waveform and the gain is adjusted taking into account the number of test bits of the set having the first binary value compared to the number of test bits in the set having the first binary value expected based on the frequency of the data code expected in the data waveform for that set.4. A method as claimed in wherein the data code is three bits long.5. A method as claimed in wherein the reference level is the target level for the data waveform for a data code having all the bits equal to the same binary value.6. A method as claimed in wherein reference level is the target level for the data waveform for a data code that results in the data waveform having a level at an extreme of those provided by codes of the same length.7. A method as claimed in wherein the ...

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Номер записи: 55

08-08-2013 дата публикации

WIRELESS NETWORKS UTILIZING MULTIPLE MODULATIONS

Номер: US20130201965A1

Автор: Batra Anuj, Hosur Srinath, SCHMIDL TIMOTHY MARK

Принадлежит: TEXAS INSTRUMENTS INCORPORATED

A method of communicating in a wireless network including a plurality of nodes having communications devices including a first node, wherein at least one node utilizes a first physical layer (PHY) modulation, and at least one other node utilizes a second PHY modulation different from the first PHY modulation. The first node receives a PHY frame transmitted by one of the plurality of nodes, and identifies a PHY modulation type selected from the first PHY modulation and the second PHY modulation used in the PHY frame or to be used in a subsequently to be received PHY frame or frame portion. The first node decodes the PHY frame or the subsequently to be received PHY frame or frame portion using the PHY modulation type identified in the identifying step. 1. A method of communicating in a wireless network including a plurality of nodes having communication devices including at a first node , at least one node utilizing a first physical layer (PHY) modulation , and at least one other node utilizing a second PHY modulation different from said first PHY modulation , said first node comprising:receiving a PHY frame transmitted by one of said plurality of nodes;identifying a PHY modulation type selected from said first PHY modulation and said second PHY modulation used in said PHY frame or to be used in a subsequently to be received PHY frame or frame portion, anddecoding said PHY frame or said subsequently to be received PHY frame or frame portion using said PHY modulation type.2. The method of claim 1 , wherein said identifying comprises performing preamble detection to a preamble of said PHY frame to determine said PHY modulation type.3. The method of claim 2 , wherein said preamble detection comprises at least one of delayed correlation and cross correlation.4. The method of claim 2 , wherein said preamble detection comprises delayed correlation and cross correlation.5. The method of claim 1 , wherein said PHY frame includes at least a preamble of a baseline PHY frame ...

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Номер записи: 56

08-08-2013 дата публикации

METHOD AND DEVICE FOR SIGNAL PROCESSING AND APPLIED TO MICROWAVE COMMUNICATION SYSTEM

Номер: US20130202022A1

Автор: CAI Meng

Принадлежит: Huawei Technologies Co., Ltd.

A method and a device which are for signal processing and are applied to a microwave communication system are disclosed. The method includes: performing equalization processing on each input signal by using an equalizer so as to obtain an equalized signal corresponding to the each input signal; performing phase estimation on phase noise in the equalized signal to obtain an estimated phase of the phase noise; performing phase rotation on the equalized signal to offset the estimated phase of the phase noise, so as to obtain a phase rotation signal; suppressing residual phase noise in the phase rotation signal by using a phase-locked loop so as to output an error signal and a received signal; and performing an iterative update on a filter coefficient of the equalizer by using the error signal. 1. A signal processing method applied to a microwave communication system , the method comprising:performing equalization processing on each input signal by using an equalizer so as to obtain an equalized signal corresponding to the each input signal;performing phase estimation on phase noise in the equalized signal to obtain an estimated phase of the phase noise;performing phase rotation on the equalized signal to offset the estimated phase of the phase noise, so as to obtain a phase rotation signal;suppressing residual phase noise in the phase rotation signal by using a phase-locked loop so as to output an error signal and a received signal; andperforming an iterative update on a filter coefficient of the equalizer by using the error signal.2. The signal processing method according to claim 1 , wherein the number of input signals is at least two claim 1 , and the method further comprises:by using a combiner, superposing all of received signals output by the phase-locked loop so as to form a received signal, wherein the number of the received signals output by the phase-locked loop is the same as the number of the input signals.3. The signal processing method according to claim ...

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Номер записи: 57

08-08-2013 дата публикации

EQUALIZER FOR AM IN-BAND ON-CHANNEL RADIO RECEIVERS

Номер: US20130202023A1

Автор: Kroeger Brian W., Wang Kun

Принадлежит:

A method is provided for equalizing OFDM symbol vectors received on AM in-band on-channel radio signal including a main carrier and first and second BPSK modulated subcarriers. The method comprises: computing a BPSK magnitude signal; filtering the BPSK magnitude signal; filtering complex samples received on the main carrier; using the filtered BPSK magnitude signal and the filtered complex samples received on the main carrier to compute a plurality of flat fade equalization coefficients; and multiplying the OFDM symbol vectors by the flat fade equalization coefficients. A receiver that includes an equalizer, which operates in accordance with the method is also provided. 1. A method of equalizing OFDM symbol vectors received on an AM in-band on-channel radio signal including a main carrier and first and second BPSK modulated subcarriers , the method comprising:computing a BPSK magnitude signal;filtering the BPSK magnitude signal;filtering complex samples received on the main carrier;using the filtered BPSK magnitude signal and the filtered complex samples received on the main carrier to compute a plurality of flat fade equalization coefficients; andmultiplying the OFDM symbol vectors by the flat fade equalization coefficients.2. The method of claim 1 , wherein the step of filtering the BPSK magnitude signal comprises:passing the BPSK magnitude signal through a median filter and a finite impulse response filter.3. The method of claim 1 , wherein the step of filtering complex samples received on the main carrier comprises:passing the complex samples received on the main carrier through a finite impulse response filter.4. The method of claim 1 , wherein the step of computing a BPSK magnitude signal comprises:extracting an absolute value of an imaginary component of a BPSK symbol.5. The method of claim 1 , wherein the first and second BPSK modulated subcarriers are modulated in quadrature to the main carrier.6. The method of claim 1 , wherein the first and second BPSK ...

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Номер записи: 58

08-08-2013 дата публикации

COMMUNICATION APPARATUS AND COMMUNICATION METHOD

Номер: US20130202060A1

Автор: NISHIKAWA Nobuyoshi

Принадлежит: Icom Incorporated

A modulator generates a modulation signal from an input signal, and a serial-parallel converter generates a subcarrier modulation signal from the modulation signal. An IFFT unit performs an inverse fast Fourier transformation on the subcarrier modulation signal to generate first data. An operator multiplies respective elements of the first data by amplitude coefficients, and further adds dispersion coefficients to the multiplication result, the amplitude coefficients being real numbers other than 0 defined for the respective elements, at least one of the amplitude coefficients having a value other than 1, the dispersion coefficients being complex numbers defined for the respective components, and at least one of the dispersion coefficients having a value other than 0. Then, data symbols are generated based on a calculation result. A transmitter transmits a transmission frame including the data symbols to another apparatus via an antenna. 1. A communication apparatus for communicating with another apparatus in orthogonal frequency-division multiplexing wireless communication , the communication apparatus comprising:a modulator that modulates an input signal using a predetermined modulation scheme, and assigns the modulated input signal to subcarriers with frequency components orthogonal to each other, thereby generating a subcarrier modulation signal;a first transformer that performs an inverse fast Fourier transformation on the subcarrier modulation signal to generate first data;an operator that multiplies respective elements of the first data by amplitude coefficients, and that further adds dispersion coefficients to the multiplication result, the amplitude coefficients being real numbers other than 0 defined for the respective elements, at least one of the amplitude coefficients having a value other than 1, the dispersion coefficients being complex numbers defined for the respective elements, and at least one of the dispersion coefficients having a value other ...

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Номер записи: 59

15-08-2013 дата публикации

FEED-FORWARD EQUALIZER ARCHITECTURES

Номер: US20130208779A1

Автор: Agrawal Ankur, Bulzacchelli John F., Friedman Daniel J., Toprak Deniz Zeynep

Принадлежит: INTERNATIONAL BUSINESS MACHINES CORPORATION

Circuits and methods are provided for efficient feed-forward equalization when sample-and-hold circuitry is employed to generate n time-delayed versions of an input data signal to be equalized. To equalize the input data signal, m data signals are input to m feed-forward equalization (FFE) taps of a current-integrating summer circuit, wherein each of the m data signals corresponds to one of the n time-delayed versions of the input data signal. A capacitance is precharged to a precharge level during a reset period of the current-integrating summer circuit. An output current is generated by each of the m FFE taps during an integration period of the current-integrating summer circuit, wherein the output currents from the m FFE taps collectively charge or discharge the capacitance during the integration period. A gating control signal is applied to an FFE tap during the integration period to disable the FFE tap during a portion of the integration period in which the data signal input to the FFE tap is invalid. 1. A feed-forward equalization circuit , comprising:delay circuitry comprising n parallel sample-and-hold circuits that are clocked by multiphase clocks to generate n time-delayed versions of an input data signal; and a first power supply node and an output node;', 'a first switch connected between the first power supply node and the output node, wherein the first switch is responsive to a reset control signal to connect the output node to the first power supply node and precharge a capacitance of the output node during a reset period of the current-integrating summer circuit, and to disconnect the output node from the first power supply node during an integrating period of the current-integrating summer circuit; and', 'a plurality of m transconductance amplifier circuits connected to the output node, wherein each of the m transconductance amplifier circuits receives as input a data signal that corresponds to one of the n time-delayed versions of the input data ...

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Номер записи: 60

15-08-2013 дата публикации

Transmitter and receiver for frequency domain equalization

Номер: US20130208781A1

Автор: Chang Yong Shin, Dong Sik Kim, Gi Hong IM, Ui Kun Kwon

Принадлежит: Academy Industry Foundation of POSTECH, SAMSUNG ELECTRONICS CO LTD

A transmitter and/or receiver for performing frequency domain equalization is provided. A transmitter includes a pilot position determination unit for determining positions for inserting pilots in a frequency domain based on frequency spectrums of data, and a pilot insertion unit for inserting the pilots between the frequency spectrums of the data according to the determined positions for inserting the pilots.

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Номер записи: 61

15-08-2013 дата публикации

TIME DOMAIN ANALOG MULTIPLICATION TECHNIQUES FOR ADJUSTING TAP WEIGHTS OF FEED-FORWARD EQUALIZERS

Номер: US20130208782A1

Автор: Agrawal Ankur, Bulzacchelli John F.

Принадлежит: INTERNATIONAL BUSINESS MACHINES CORPORATION

Feed-forward equalizer (FFE) circuits and methods are provided which implement time domain analog multiplication for adjusting FFE tap weights. For example, a method includes inputting data signals to FFE taps of a current-integrating summer circuit, wherein the data signals are time-delayed versions of an analog input data signal. A capacitance is charged to a precharge level during a reset period of the current-integrating summer circuit. An output current is generated by each FFE tap during an integration period of the current-integrating summer circuit. The output currents from the FFE taps collectively charge or discharge the capacitance during the integration period. A gating control signal is applied to a given FFE tap during the integration period to enable the given FFE tap during a portion of the integration period in which the gating control signal overlaps the integration period so as to effectively multiply the data signal input to the given FFE tap with an FFE coefficient value corresponding to a period of overlap between the gating control signal and the integration period. 1. A feed-forward equalization (FFE) circuit , comprising:delay circuitry to generate n time-delayed versions of an analog input data signal;a current-integrating summer circuit; anda gating signal generator circuit that receives a clock signal and an FFE coefficient value and generates a gating control signal based on the clock signal and the FFE coefficient value, wherein the gating control signal has a phase-shift with respect to a reset control signal wherein the reset control signal defines a reset period and an integration period for the current-integrating summer circuit, and wherein the phase-shift provides an overlap period between the gating control signal and the integration period, which corresponds to the FFE coefficient value, a first power supply node and an output node;', 'a first switch connected between the first power supply node and the output node, wherein the ...

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Номер записи: 62

15-08-2013 дата публикации

SYSTEM FOR SIMULTANEOUS TRANSMISSION OF MORSE SIGNALLING OVER A RADIO COMMUNICATION USING DIGITAL TECHNOLOGY

Номер: US20130208829A1

Автор: ABADIAS PELACHO Roman, CANO LAZARO Ignacio, CORDOVA VAL Javier

Принадлежит: TELTRONIC, S.A.

System for simultaneous transmission () of Morse signaling over a radio communication using digital technology, comprising: 22. The system for transmission according to claim 1 , wherein the signal generated by the signal generator () is a radiofrequency (RF) signal.3542453. The system for transmission according to claim 1 , wherein it additionally comprises a modulator () which is connected to the output of the first attenuator module () claim 1 , and that the signal produced by the signal generator () is a signal in the baseband; in such a way that the signal in the baseband attenuated by the first attenuator module () reaches the modulator () claim 1 , which generates a radiofrequency (RF) signal with digital modulation where there is at least one amplitude modulation component claim 1 , in such a way that the attenuation in amplitude is function of the amplitude of the waveform generated by the Morse code generator (). The present invention relates to a system for the simultaneous transmission of Morse signaling over a radio communication using digital technology, the digital modulation used having an amplitude modulation component of the radiofrequency (RF) carrier signal and the transmission being carried out by means of an analog amplitude modulation (AM) over the same radiofrequency RF carrier of a Morse code corresponding to an identifier assigned to the radio transmitter, enabling that at the moment of the transmission of said identifier, the digital service is not interrupted.Therefore, the objective is to be able to simultaneously transmit digital and analog signals without information loss of either signal.The invention is for use in the radio communications industry for those countries where it is required that each one of the radio transmitters that comprise a network, emit a unique identifier by means of voice or Morse code.Currently, there are digital radio communication systems that allow, through their digital modulations, to provide an ...

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Номер записи: 63

22-08-2013 дата публикации

COMMUNICATION APPARATUS, CIRCUIT FOR COMMUNICATION APPARATUS, AND COMMUNICATION METHOD

Номер: US20130215763A1

Автор: Honda Mitsuhiro

Принадлежит:

In a communication apparatus which performs wireless communication over a plurality of lines, a reduction in transmission efficiency is prevented from occurring. A communication apparatus is provided with: a plurality of reception units which receive signals of the same content from an opposed station over a plurality of lines using wireless communication; a quality determination unit which determines qualities of the plurality of lines based on the received signals of the same content; a modulation scheme determination unit which determines a modulation scheme to be used for the wireless communication based on the quality of only a line over which communication is possible when it becomes impossible to perform communication over a line among the plurality of lines; and a transmission unit which transmits information indicating the determined modulation scheme to the opposed station. 1. A communication apparatus comprising:a plurality of reception units which receive signals of the same content from an opposed station over a plurality of lines using wireless communication;a quality determination unit which determines qualities of the plurality of lines based on the received signals of the same content;a modulation scheme determination unit which determines a modulation scheme to be used for the wireless communication based on the quality of only a line over which communication is possible when it becomes impossible to perform communication over a line among the plurality of lines; anda transmission unit which transmits information indicating the determined modulation scheme to the opposed station.2. The communication apparatus according to claim 1 , wherein when communication is possible over all the plurality of lines claim 1 , the modulation scheme determination unit determines the modulation scheme to be used for the wireless communication based on the qualities of all the lines.3. The communication apparatus according to claim 1 , further comprising a line ...

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Номер записи: 64

22-08-2013 дата публикации

Measurement of intermodulation products of digital signals

Номер: US20130215953A1

Автор: Currivan Bruce J., Kolze Thomas J.

Принадлежит: BROADCOM CORPORATION

Measurement of intermodulation products of digital signals. One or more devices, within a communication system, having and analog to digital converter (ADC) with a sufficiently wide frequency response as to capture not only a signal of interest, but many other signals simultaneously, allows for appropriate signal processing of such captured samples to identify one or more intermodulation products that may exist as a function of the relationship of one or more frequencies. For example, composite second order (CSO) or composite triple beat (CTB), or even higher ordered signals, may occur within various communication systems. These effects may be caused by any of a number of sources including nonlinearities in the system, such as affects associated with laser clipping, amplifier compression, corroded connectors, etc. Appropriate processing is performed determine the existences of such intermodulation product signals, and, if desired, subsequent signal processing and/or fixing of such effects therein is performed. 1. An apparatus , comprising:an analog to digital converter (ADC) to capture a plurality of samples of a first signal corresponding to a first frequency and at least one additional signal corresponding to at least one additional frequency, wherein the ADC having a wideband frequency response spanning at least the first frequency and the at least one additional frequency and at least one intermodulation product corresponding to at least one of the first frequency and the at least one additional frequency; and identify a correlation between the at least the first frequency and the at least one additional frequency and the at least one intermodulation product corresponding to the first frequency and the at least one additional frequency;', 'based on identification of the correlation, characterize the correlation as corresponding to at least one of a plurality of events, including at least one clipping event and at least one non-clipping event, affecting a ...

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Номер записи: 65

22-08-2013 дата публикации

Overlay Modulation Technique for COFDM Signals Based on Amplitude Offsets

Номер: US20130215984A1

Автор: Carl Scarpa, Christopher Strolle, Edward Schell

Принадлежит: Sirius XM Radio Inc

Systems and methods are presented for transmitting additional data over preexisting differential COFDM signals by changing the amplitude of the legacy data symbols. In exemplary embodiments of the present invention, additional data capacity can be achieved for a COFDM signal which is completely backwards compatible with existing legacy satellite broadcast communications systems. In exemplary embodiments of the present invention, additional information can be overlaid on a legacy COFDM signal by applying an amplitude offset to the legacy symbols. In exemplary embodiments of the present invention, special receiver processing can be implemented to extract this additional information, which can include performing channel equalization across frequency bins to isolate the amplitude modulated overlay signal. For example, at each FFT symbol time, average power across neighboring active data bins can be used to determine the localized power at the corresponding FFT bins, and a channel inversion can then, for example, be performed on the data bins to restore, as best as possible, the original transmitted symbol amplitude.

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Номер записи: 66

22-08-2013 дата публикации

Multiple-Mode Digital Modulation Using a Single Square-Root Nyquist Pulse-Shaping Transmit Filter

Номер: US20130215990A1

Автор: Jaspar Michael A., Larionov Nikolaj

Принадлежит: VECIMA NETWORKS INC.

In a method of digital communication where the transmitter includes a pulse-shaping filter and the receiver includes a plurality of corresponding matched filters, the pulse shaping filter is approximated to match a plurality of filters of the receiver for reducing the number of transmit shaping filters. The filter comprises a square-root raised cosine (SRRC) filter where the SRRC filter amplitude/phase response is approximated using a typical Parks-McClellan (remez) algorithm for designing linear phase FIR filters which, for a given set of input parameters, outputs a transmit filter coefficient set for the SRRC filter. The input parameters to the Parks-McClellan algorithm are chosen by iteration such that pass-band ripple, 3-dB point, and stop-band attenuation of the transmit filter meet or exceed specification requirements while the resulting transmit-receive filter pair ISI is minimized across a plurality of matched filter specifications. 1. A method of digital communication comprising:providing in a transmitter a pulse-shaping filter;providing in a receiver a plurality of corresponding matched filters;wherein each pulse-shaping filter comprises a raised-cosine (RC) or square-root raised cosine (SRRC) filter;and wherein the pulse-shaping filter of the transmitter has a frequency response which is approximated so as to match, within the required standards, a plurality of the matched filters of the receiver.2. The method of wherein the coefficient set is chosen such that the approximated transmit filter frequency response meets or exceeds the following requirements of one or more standards: pass-band ripple', '3 dB point', 'stop-band attenuation and adjacent channel noise performance., 'general transmit filter shape (i.e. RC or SRRC) includinga minimum modulation-error ratio (MER), relating to ISI performance of the transmit-receive filter pair.3. The method of wherein the approximations of the frequency response are chosen such that MER and ISI performance of the ...

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Номер записи: 67

22-08-2013 дата публикации

COMMUNICATION APPARATUS AND COMMUNICATION METHOD

Номер: US20130215994A1

Автор: NISHIKAWA Nobuyoshi

Принадлежит: Icom Incorporated

A serial-parallel converter generates a subcarrier modulation signal from a modulation signal which is generated from the input signal by a modulator. An IFFT unit performs an inverse fast Fourier transformation on the subcarrier modulation signal. A divider divides a calculation result to generate first subdata. A disperser adds dispersion coefficients to elements of first subdata. A sorter generates second subdata from post-dispersion first subdata. An operator performs a predetermined calculation using elements in the same line of the post-dispersion first subdata and second subdata. A corrector subtracts correction coefficients from elements of post-average first subdata. A synthesizer arranges post-correction first subdata in positions at the time of division and synthesizes them to generate a baseband signal. A transmitter generates a transmission signal to transmit. 1. A communication apparatus for communicating with another apparatus in orthogonal frequency-division multiplexing wireless communication , the communication apparatus comprising:a modulator that modulates an input signal using a predetermined modulation scheme, and assigns the modulated input signal to subcarriers with frequency components orthogonal to each other, thereby generating a subcarrier modulation signal;a first transformer that performs an inverse fast Fourier transformation on the subcarrier modulation signal;a divider that divides a calculation result by the first transformer into a predetermined number of pieces to generate a plurality pieces of first subdata;a disperser that adds dispersion coefficients, which are complex numbers defined for each first subdata and of which at least one is a complex number other than 0, to values of respective elements of the plurality pieces of first subdata to generate post-dispersion first subdata;a sorter that generates second subdata in which each element of the post-dispersion first subdata is arranged in a position different from a position ...

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Номер записи: 68

22-08-2013 дата публикации

LOW-LATENCY VITERBI SURVIVOR MEMORY ARCHITECTURE AND METHOD USING REGISTER EXCHANGE, TRACE-BACK, AND TRACE-FORWARD

Номер: US20130216006A1

Автор: KOSAKOWSKI Martin

Принадлежит: RESEARCH IN MOTION LIMITED

In various aspects, the disclosure describes systems and methods for decoding of convolutionally encoded signals representing, for example, telecommunications signals such as command or content signals used in digital telecommunications. In various embodiments such aspects of the disclosure provide systems and methods for improving the efficiency, speed, and power consumption of such processes by providing architectures and methods for processing various parts of the encoded data records in parallel, using multiple and optionally specially-designed, dedicated memory registers and multiplexers. 1. A method , performed by a data processor , for processing electromagnetic signals representing convolutionally encoded data streams , the method comprising: storing decision bit data representing results of the trellis search for a first D bits of the convolutionally encoded data stream in a (D×N)-bit register accessible by the processor, where D is an integer greater than zero and less than L, and ordering the decision bit data according to the results of the trellis search for the first D bits of the convolutionally encoded data stream;', 'storing decision bits representing results of the trellis search for a subsequent L-D bits of the convolutionally encoded data stream in random access memory accessible by the processor; and, 'while performing a trellis search of a convolutionally encoded data stream of bit length L, where L is an integer{'sup': 'st', 'upon completion of the trellis search for the first D bits of the convolutionally encoded data stream, commencing a first trace-forward process of the results of the trellis search, starting with a (D+1)bit of the convolutionally encoded data stream; and'}{'sup': st', 'th, 'commencing at least one trace-back process to decode the stored decision bits in the random access memory corresponding to the (D+1)through Lbits of the convolutionally encoded data stream, and storing decoded bits determined by the at least one trace- ...

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Номер записи: 69

29-08-2013 дата публикации

Flexible adaptive equalizer

Номер: US20130223506A1

Автор: Kolze Thomas J.

Принадлежит: BROADCOM CORPORATION

Flexible adaptive equalizer. Communications may be supported between two or more respective devices within a communications system via one or more available channels. Such channels may be different respective communication channels or may be logical partitions of a given communication channel. Appropriate adaptation and provision of resources within one or more devices within the system may be performed based upon any of a number of characteristics and/or considerations associated with one or more devices, channels, etc. within the system. A number of equalizer elements may be employed to perform processing of respective signal(s) received via respective channel(s). Adaptation of which equalizer elements are employed for the respective channels may be modified, adapted, etc. over time based upon any of such number of characteristics and/or considerations. Also, a number of pre-equalizer elements may also be employed to perform processing of signal(s) to be transmitted via respective channel(s). 1. An apparatus , comprising:at least one communication interface to support communications with at least one communication device via a plurality of communication channels including to receive a plurality of signals corresponding respectively to the plurality of communication channels such that each of the plurality of signals corresponding to a respective one of the plurality of communication channels; anda plurality of equalizer elements adaptively connectable, in any of a plurality of configurations, to process the plurality of signals, wherein all of the plurality of equalizer elements or any subset of the plurality of equalizer elements to process at least one of the plurality of signals to generate a processed signal or a plurality of processed signals;a processor to perform a least means square (LMS) optimization process to select a plurality of equalizer tap coefficients corresponding to at least one of the plurality of equalizer elements based on at least one ...

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Номер записи: 70

29-08-2013 дата публикации

System and method for efficient frequency estimation in burst-mode communication

Номер: US20130223544A1

Автор: Neal Becker

Принадлежит: HUGHES NETWORK SYSTEMS LLC

Aspects of the invention provide a method of introducing pilot symbols for synchronization that minimizes overhead while allowing for a large frequency uncertainty by inserting the pilot groups non-periodically in burst communication systems. The pilot sequence could be used for establishing all synchronization, including timing, frequency and phase, or, alternatively, it could be used only for carrier phase and frequency estimation with some other means used for establishing start-of-burst timing.

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Номер записи: 71

29-08-2013 дата публикации

Method, Apparatus, and System for Coding and Modulating Data

Номер: US20130223545A1

Автор: Xu Shugong, Zhang Shunqing

Принадлежит: Huawei Technologies Co., Ltd.

A method, an apparatus, and a system for coding and modulating data are disclosed. The method includes: obtaining, from a receiver and a transmitter, parameters for calculating power consumption of the transmitter; calculating, according to the parameters, the power consumption of the transmitter under various combinations of modulation orders and coding rates supported by the transmitter; and selecting a bitwidth, modulation order, and coding rate corresponding to minimum power consumption of the transmitter to code and modulate data sent to the receiver. The method, apparatus, and system provided in embodiments of the present application save power consumption of the transmitter, and greatly improve energy utilization of a wireless device having a digital processing unit. 1. A method for coding and modulating data comprising:obtaining, from a receiver and a transmitter, parameters for calculating power consumption of the transmitter;calculating, according to the parameters, the power consumption of the transmitter under various combinations of modulation orders and coding rates supported by the transmitter; andselecting a bitwidth, modulation order, and coding rate corresponding to minimum power consumption of the transmitter to code and modulate data sent to the receiver.2. The method according to claim 1 , wherein the parameters comprise a supported bitwidth fed back by the receiver and a bitwidth feature of the transmitter.3. The method according to claim 2 , wherein calculating claim 2 , according to the parameters claim 2 , the power consumption of the transmitter under various combinations of modulation orders and coding rates supported by the transmitter comprises:determining an upper bitwidth threshold according to the supported bitwidth of the receiver;obtaining a quantized noise of the transmitter by calculation;using a bitwidth corresponding to the quantized noise as a lower bitwidth threshold;selecting a plurality of available bitwidths of the ...

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Номер записи: 72

05-09-2013 дата публикации

Self-calibrating continuous-time equalization

Номер: US20130230089A1

Автор: Timothy Hollis

Принадлежит: Micron Technology Inc

Embodiments of the invention comprise a continuous-time equalizer for reducing ISI in data received from a communication channel, and methods and circuitry for tuning or calibrating that equalizer. Selected coefficients for a transfer function of the equalizer circuit are fixed, while other coefficients are tuned by an adaptive algorithm. The adaptive algorithm minimizes errors associated with the tunable coefficients based on one or more training signals sent by the transmitter and received by the equalizer circuit at the receiver. The training signals allow for a variety of error terms to be calculated, from which the tunable coefficients are updated so as to iteratively minimize the error terms and simultaneously tune the equalizer to more accurately compensate for the degrading effects of the channel.

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Номер записи: 73

12-09-2013 дата публикации

ADAPTIVE MODULATION FOR COOPERATIVE CODED SYSTEMS

Номер: US20130235793A1

Автор: Erkip Elza, Ghosh Monisha, Lin Zinan

Принадлежит:

A system (), method, and apparatus () are provided for a source to choose a partner/relay from at least one candidate() () to transmit at least part of a message from the source () to destination (). The choice depends on the channel conditions of the source () and when the source is experiencing poor channel quality to the destination, the source selects the candidate and the modulation modes of the source () and partner/relay () () such that the frame error rate (FER) of the source() is lowered. Otherwise, a modulation mode is selected for each of the source () and the partner/relay () () that most improves the gain in throughput of the source (). The present invention applies to modes consisting of binary phase shift keying (BPSK), quadrature phase shift keying (QPSK), and 16-state quadrature amplitude modulation (16-QAM). 1. At least one candidate partner/relay of a source in a wireless coded cooperative communication system , having an adaptable modulation mode and being adapted to perform a pre-determined coded cooperative communication protocol to forward signals received from the source to a destination ,wherein, based on the channel conditions of a pair consisting of the source and the at least one candidate, the source chooses the candidate and a corresponding pair of modulation mode settings consisting of a setting for each of the candidate modulation mode for transmission between the candidate partner/relay and the destination and the source modulation mode that provide for transmission between the source and the candidate partner/relay, wherein the throughput gain that is improved more than the throughput gain of any other choice for the candidate and the corresponding pair of modulation mode settings.2. The at least one candidate partner/relay of a source of claim 1 , wherein the throughput gain that is improved more than any other is determined by:when the source is experiencing poor channel quality to the destination, the source selects the candidate ...

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Номер записи: 74

12-09-2013 дата публикации

RECEIVING APPARATUS AND METHOD FOR RECEIVING SIGNALS IN A WIRELESS COMMUNICATION SYSTEM WITH IMPROVED EQUALIZATION PERFORMANCE

Номер: US20130235922A1

Автор: WANG Qi, WANG Zhaocheng

Принадлежит:

Described herein is a receiving apparatus and method for receiving signals in a wireless communication system, the signals including a dedicated channel estimation sequence, including a gain control means that controls the gain of a received signal, a channel estimation means that performs a channel estimation on the basis of a dedicated channel estimation sequence included in a received signal, a gain error correction means that corrects a gain error in the result of said channel estimation caused by said gain control means on the basis of the dedicated channel estimation sequence comprised in the received signal, and an equalizing means that performs an equalization on the received signal on the basis of the gain corrected channel estimation result. 1. Receiving apparatus for receiving signals in a communication system , in which the signals comprise a dedicated channel estimation sequence , comprisinga gain control unit adapted to control the gain of a received signal,a channel estimation unit adapted to perform a channel estimation on the basis of a dedicated channel estimation sequence comprised in a received signal,a gain error correction unit adapted to correct a gain error in the result of said channel estimation caused by said gain control unit on the basis of said dedicated channel estimation sequence comprised in the received signal, andan equalizing unit adapted to perform an equalization on the received signal on the basis of the gain corrected channel estimation result.2. Receiving apparatus according to claim 1 ,wherein said gain error correction unit comprises a gain error calculation unit adapted to obtain a gain error of said dedicated channel estimation sequence comprised in the received signal and a correction unit adapted to correct a gain error in the result of the channel estimation performed by said channel estimation unit on the basis of the gain error obtained in said gain error calculation unit.3. Receiving apparatus according to claim 2 , ...

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Номер записи: 75

12-09-2013 дата публикации

System and Method of Processing a Satellite Signal

Номер: US20130239152A1

Автор: Ansari Ahmad, Medford Brad Allen, Nadarajah Dinesh

Принадлежит: AT&T Intellectual Property I, L.P. (formerly known as SBC Knowledge Ventures, L.P.)

A system includes a converter to receive a receiving a satellite signal at first transport frequencies and to convert the satellite signal to second transport frequencies and a processor. The processor removes a radio frequency portion from the satellite signal without altering a sequence of media contents of a moving picture experts group portion of the satellite signal and without altering a quality of the media contents of the moving picture experts group portion. The processor determines whether the media contents include an error and corrects the error in the moving picture experts group portion with error correction data of the satellite signal. The processor encrypts the media contents to produce an encrypted digital moving picture experts group transport stream signal. The processor also sends the encrypted digital moving picture experts group transport stream signal to a modulator. 1. A method comprising:receiving at a receiver from a satellite dish a satellite signal;removing an initial radio frequency portion from the satellite signal without altering a sequence of media contents of a moving picture experts group portion of the satellite signal and without altering a quality of the media contents of the moving picture experts group portion;removing an initial conditional access portion from the satellite signal without altering the sequence of media contents of the moving picture experts group portion of the satellite signal and without altering a quality of the media contents of the moving picture experts group portion;decoding the satellite signal at the receiver to produce a digital moving picture experts group transport stream signal that includes the moving picture experts group portion;correcting an error in the moving picture experts group transport stream signal using error correction data of the satellite signal to generate a corrected digital moving picture experts group transport stream signal;encrypting the corrected digital moving picture ...

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Номер записи: 76

26-09-2013 дата публикации

METHOD FOR IDENTIFYING AND DETECTING A RADIO SIGNAL FOR A COGNITIVE COMMUNICATION SYSTEM

Номер: US20130251014A1

Автор: GAUTIER Matthieu, Noguet Dominique

Принадлежит:

A method of identifying an RF signal for a cognitive radio system. The signal is identified with a digital watermarking performed downstream from the digital modulation of the symbols to be transmitted. A method of detecting an RF signal watermarked is also disclosed. The identification method includes demodulating the received RF signal as a baseband, converting it digitally, and correlating the digital signal obtained with a predetermined digital signature. The correlation values are averaged using a recursive filter and the maximum value of the average values output from the filter is compared to a threshold to decide whether the RF signal is present. 1. A method for identifying an RF signal for a cognitive radio system , the method comprising:performing a digital modulation of symbols to be transmitted to obtain a stream of modulation symbols;adding a digital signature to the stream of modulation signals to obtain a watermarked signal, where said signature has an amplitude substantially lower than said modulation symbols;transposing the watermarked signal into an RF band.2. An identification method according to claim 1 , wherein the watermarked signal is obtained by digitally adding the digital signature to the stream of modulation symbols claim 1 , and by performing a digital-analog conversion of the resulting stream.3. An identification method according to claim 1 , wherein the watermarked signal is obtained by performing a digital-analog conversion of the stream of modulation symbols claim 1 , firstly claim 1 , to generate a first analog signal claim 1 , and of the digital signature claim 1 , secondly claim 1 , to generate a second analog signal claim 1 , and by summing the first and second analog signals obtained in this manner.4. An identification method according to claim 1 , wherein the digital signature is a Gold code.5. An identification method according to claim 1 , wherein the digital signature is a Hadamard code.6. An identification method according ...

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Номер записи: 77

26-09-2013 дата публикации

ASK SIGNAL GENERATOR

Номер: US20130251067A1

Автор: FUJIMOTO Ryuichi

Принадлежит: KABUSHIKI KAISHA TOSHIBA

According to one embodiment, an ASK signal generator includes a differential oscillator, a first modulator, a second modulator, a first transmission line, a second transmission line and an impedance adjustment circuit. The differential oscillator generates first and second signals having an opposite phase, and outputs the first and second signals from first and second output terminals. The first modulator connected to the first output terminal is set in the normally off state. The second modulator connected to the second output terminal is turned on or off according to a digital signal. The first and second transmission lines connected to the first and second output terminals have a length equal to a ¼ wavelength of the oscillation frequency of the differential oscillator. The impedance adjustment circuit is operated together with the second modulator according to the digital signal. 1. An ASK signal generator comprising:a differential oscillator configured to include first and second output terminals and generate a first signal and a second signal with an opposite phase of the first signal, the differential oscillator outputting the first signal from the first output terminal and outputting the second signal from the second output terminal;a first modulator connected to the first output terminal of the differential oscillator, configured to be set in a normally off state;a second modulator connected to the second output terminal of the differential oscillator, configured to turn on/off according to a modulated signal;a first transmission line connected to the first output terminal of the differential oscillator and having a length equal to a ¼ wavelength of the oscillation frequency of the differential oscillator;a second transmission line connected to the second output terminal of the differential oscillator, having a length equal to a ¼ wavelength of the oscillation frequency of the differential oscillator and having an output terminal connected to an output ...

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Номер записи: 78

26-09-2013 дата публикации

DATA RECEIVING CIRCUIT AND DATA RECEIVING METHOD

Номер: US20130251077A1

Автор: Hasegawa Hideaki, Ike Yuuichi, Itou Toshio, TAKEDA Kouji

Принадлежит: LAPIS SEMICONDUCTOR CO., LTD.

A data receiving circuit an a data receiving method accurately acquire a data signal corresponding to information data from a high speed high density transmitted signal. An increase or a decrease of the level of one of a amplified data signal and a level converted data signal that is transmitted from one, referred to as one processing stage, of an amplification processing stage and a level converting processing stage, is fed back to a stage preceding the one processing stage. The amplification processing stage supplies, to a first line, an amplified data signal obtained by performing an amplification processing on a received data signal, and the level converting processing stage transmits, via a second line, a level converted data signal obtained by performing a level converting processing on the amplified data signal. 1. A data receiving circuit comprising:an amplification processing stage that supplies an amplified data signal on a first line, said amplified data signal being obtained by performing an amplification process on a received data signal; anda level converting processing stage that transmits a level converted data signal via a second line, said level converted data signal being obtained by performing a level conversion processing on said amplified data signal,wherein said data receiving circuit further comprises an amplitude controlling part that feeds back an increase or decrease of one of said amplified data signal and said level converted data signal transmitted from one of said amplification processing stage and said level converting processing stage to a stage preceding said one of said amplification processing stage and said level converting processing stage.2. The data receiving circuit according to claim 1 , wherein said amplitude controlling part performs a control that the lower the level of a data signal transmitted from said one of said amplification processing stage and said level converting processing stage claim 1 , the higher the level ...

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Номер записи: 79

24-10-2013 дата публикации

Dynamic Polarization Modulation and Control

Номер: US20130279631A1

Автор: Bowers Steven, Dasgupta Kaushik, Hajimiri Seyed Ali, Tabbalvandani Amirreza Safaripour

Принадлежит:

A method for sending a data from an electromagnetic radiator by polarization modulation of an electromagnetic wave includes radiating from the radiator first and second electromagnetic waves including first and second polarizations respectively, the first polarization being different than the second polarization. The first and second electromagnetic waves form a third electromagnetic wave having a third polarization different from the first or second polarization. The method includes modulating the third polarization responsive to the data by modulating one or more parts of the third electromagnetic wave. The data is sent in the third polarization. A system for sending a data includes an oscillator adapted to generate an oscillating signal, and a phase shifter coupled to the oscillator and adapted to generate a first phase-shifted oscillating signal having a first phase. The phase shifter is adapted to vary the phase difference across a predefined range in response to the data. 1. A method for sending a data from an electromagnetic radiator by polarization modulation of an electromagnetic wave , the method comprising:radiating from the radiator a first electromagnetic wave including a first polarization;radiating from the radiator a second electromagnetic wave including a second polarization different than the first polarization, the first and second electromagnetic waves forming a third electromagnetic wave having a third polarization different from the first or second polarization; andmodulating the third polarization responsive to the data by modulating one or more parts of the third electromagnetic wave, wherein the data is sent in the third polarization.2. The method of claim 1 , wherein the first electromagnetic wave includes a first phase and the second electromagnetic wave includes a second phase claim 1 , wherein the one or more parts are selected from the group consisting of the first phase claim 1 , and the second phase.3. The method of claim 1 , wherein ...

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Номер записи: 80

31-10-2013 дата публикации

FRAME STRUCTURE FOR A QAM SYSTEM

Номер: US20130287142A1

Автор: FIMOFF Mark, Jin Jinghua, Kim Jin H.

Принадлежит:

A novel framing method for a variable net bit rate digital communications system that utilizes a set of different QAM constellations and punctured trellis code combinations, each combination designated as a mode. This frame structure has a variable integral number of QAM symbols per frame depending on the selected mode, but the number of bytes and Reed-Solomon packets per frame is constant. This is achieved even though the number of data bits per QAM symbol for some modes is fractional. Also the number of trellis coder puncture pattern cycles per frame is an integer for all modes. This arrangement simplifies the synchronization of receiver processing blocks such as the Viterbi decoder, de-randomizer, byte de-interleaver, and Reed-Solomon decoder. 1. A method for variable net bit rate digital communications comprising:generating a forward error correction (FEC) data frame from one or more interleaved Reed-Solomon (RS) packets, each RS packet encoding a plurality of data bytes;modulating a plurality of bits of the FEC data frame using a punctured trellis coder that is operated at a selected code rate, the code rate being selected based on white noise performance of a digital communications system;mapping the modulated bits to quadrature amplitude modulation (QAM) symbols using a QAM constellation selected from a set of candidate QAM constellations; andproviding a transmission frame comprising the QAM symbols and a indication of a transmission mode, the transmission mode identifying the selected code rate and the QAM constellation selected from the set of candidate QAM constellations,wherein a constant number of RS packets is provided in each of a plurality of transmission frames regardless of transmission mode selected for the each transmission frame.2. The method of claim 1 , wherein each of the plurality of transmission frames comprises a variable integral number of QAM symbols.3. The method of claim 1 , wherein an integer number of Reed-Solomon packets is provided ...

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Номер записи: 81

14-11-2013 дата публикации

DATA RECEIVER, DATA COMMUNICATION SYSTEM, AND DATA COMMUNICATION METHOD

Номер: US20130301695A1

Автор: Nishi Ryohsuke

Принадлежит:

A data receiver is disclosed, including an equalization process part, a multi-value oversampling part, and an equalization controller. The equalization process part equalizes serial received data before binarization and outputs the serial received data being equalized. The multi-value oversampling part binarizes the serial received data being equalized by multiple threshold values, conducts oversampling, and generates the multi-value sampling data. The equalization controller detects an eye pattern of the serial received data being equalized based on the multi-value oversampling data, and controls an equalization characteristic of the equalization process part based on a detection result. 1. A data receiver , comprising:an equalization process part configured to equalize serial received data before binarization and to output the serial received data being equalized;a multi-value oversampling part configured to binarize the serial received data being equalized by multiple threshold values, to conduct oversampling, and to generate the multi-value sampling data; andan equalization controller configured to detect an eye pattern of the serial received data being equalized based on the multi-value oversampling data, and to control an equalization characteristic of the equalization process part based on a detection result.2. The data receiver as claimed in claim 1 , wherein the equalization controller is configured to detect the eye pattern based on the multi-value sampling data claim 1 , which are sampled with a same clock claim 1 , in data acquired by conducting a multi-value oversampling for a set of symbol data.3. The data receiver as claimed in claim 2 , wherein the equalization controller is configured to:calculate an Exclusive OR for sets of adjacent data of the multi-value sampling data, which are sampled with the same clock, in data in which the set of the symbol data is acquired by the multi-value oversampling;add calculation results of the Exclusive OR ...

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Номер записи: 82

21-11-2013 дата публикации

Method and System for Adaptive Tone Cancellation for Mitigating the Effects of Electromagnetic Interference

Номер: US20130308695A1

Автор: Ahmad Darabiha, Kadir Dinc, Kishore Kota, Mehdi Tavassoli Kilani, Scott Powell, Tooraj Esmailian

Принадлежит: Broadcom Corp

Aspects of a method and system for adaptive tone cancellation for mitigating the effects of interference are provided. In this regard, an Ethernet PHY may receive one or more signals via a corresponding one or more physical channels and generate one or more estimate signals, each of which approximates interference present in a corresponding one of the received signals. The Ethernet PHY may subtract each one of the estimate signals from a corresponding one of the received signals. The subtracting may occur at the input of one or more slicers in the Ethernet PHY. The received signals may be processed via one or more equalizers in the Ethernet PHY. A decision output of a slicer in the Ethernet PHY may be subtracted from one of the the one or more received signals, and a signal resulting from the subtraction may be utilized to generate the one or more estimate signals.

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Номер записи: 83

28-11-2013 дата публикации

OFDM PRE-EQUALIZING

Номер: US20130315292A1

Автор: BÖHNKE Ralf, IZUMI Seiichi

Принадлежит: Sony Deutschland GmbH

For example in case of an OFDM multicarrier transmission system the transmission characteristics of subcarriers of a multicarrier transmission system using a plurality of antenna elements () can be adjusted. Particularly the power and the phase of the subcarriers can be adapted. To this object the subcarrier frequency channel () characteristics of the multicarrier transmission are detected () at the side of the transmitter (). The power of each subcarrier is then distributed by a weighting unit (). The subcarriers can be further pre-equalized () by dividing the subcarrier signal respectively by the sum of the squared magnitude of the frequency channel characteristics of all subcarrier signals or a frequency characteristic of the selected antenna element (). 1. Method for adjusting the transmission characteristics of subcarriers of a multi-carrier transmission system using a plurality of antenna elements , the method comprising the following steps at the transmitting side:{'b': 11', '11', '2', '2, 'detecting (, ′) the subcarrier frequency channel (, ′) characteristics of the multicarrier transmission, and'}{'b': 1', '1', '10', '10', '2', '2', '2', '2, 'pre-equalizing (, ′, , ′) the power of each subcarrier by dividing it by the amplitude characteristics of the corresponding subcarrier frequency channel (, ′) or all subcarrier frequency channels to compensate for the power profile of the channel(s) (, ′).'}2. The method of claim 16 , wherein the adjusting step comprises:compensating, respectively, the phase of the subcarrier signals at a transmission side according to the detected frequency channel characteristics.3. The method of claim 16 , further comprising the step of:selecting for transmission, an antenna element having the best channel characteristics for the subcarrier signal, based on the detected frequency channel characteristics at each antenna element for each subcarrier signal.4. The method of claim 16 , further comprising the step of:distributing the ...

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Номер записи: 84

05-12-2013 дата публикации

HIGH-SPEED SIGNALING SYSTEMS WITH ADAPTABLE PRE-EMPHASIS AND EQUALIZATION

Номер: US20130322506A1

Автор: Chen Fred F., Donnelly Kevin S., Farjad-Rad Ramin, Ho Andrew, Leibowitz Brian S., Poulton John W., Zerbe Jared L.

Принадлежит: Rambus, Inc.

A signaling system includes a pre-emphasizing transmitter and an equalizing receiver coupled to one another via a high-speed signal path. The receiver measures the quality of data conveyed from the transmitter. A controller uses this information and other information to adaptively establish appropriate transmit pre-emphasis and receive equalization settings, e.g. to select the lowest power setting for which the signaling system provides some minimum communication bandwidth without exceeding a desired bit-error rate. 1. An integrated circuit , comprising: a continuous time linear equalizer (CTLE) to equalize the signal, the CTLE having at least one adjustable setting, the at least one adjustable setting providing at least one of adjustable gain and adjustable frequency response, and', 'a decision feedback equalizer (DFE) to further equalize the signal using at least one tap and a respective tap weight for each tap; and, 'receiver circuitry to receive a signal from over a serial link external to the integrated circuit, the receiver circuitry including'}logic to automatically determine the at least one adjustable setting and each respective tap weight in dependence on at least one measured performance characteristic affective transmission over the serial link.2. The integrated circuit of claim 1 , wherein the logic is to repeatedly and automatically update the at least one adjustable setting and each respective tap weight during run-time of the integrated circuit.3. The integrated circuit of claim 2 , wherein:the at least one tap comprises at least five taps; andthe logic is to automatically determine the at least one adjustable setting and the respective tap weight for each tap of the at least five taps.4. The integrated circuit of claim 1 , wherein:in a high-performance mode, the logic is to adaptively determine the at least one setting adjustable setting and each respective tap weight; andin a low-power mode, the logic is to adaptively determine each setting of the ...

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Номер записи: 85

12-12-2013 дата публикации

RECEIVER AND METHOD OF CONTROLLING A RECEIVER

Номер: US20130329773A1

Автор: CHEN Zhiming, Cheng Kuang-Wei, JE Minkyu, Xue Rui-Feng, Zheng Yuanjin

Принадлежит:

According to embodiments of the present invention, a receiver is provided. The receiver includes an envelope detector configured to generate a waveform corresponding to an envelope of a signal received by the receiver, a carrier recovery circuit configured to generate a carrier signal based on the waveform, wherein the carrier signal has a frequency corresponding to a center frequency of the received signal, and a template generator configured to generate a local template signal based on the waveform, the local template signal including a plurality of pulses. According to further embodiments of the present invention, a method of controlling a receiver is also provided. 1. A receiver comprising:an envelope detector configured to generate a waveform corresponding to an envelope of a signal received by the receiver;a carrier recovery circuit configured to generate a carrier signal based on the waveform, wherein the carrier signal has a frequency corresponding to a center frequency of the received signal; anda template generator configured to generate a local template signal based on the waveform, the local template signal comprising a plurality of pulses.2. The receiver of claim 1 , further comprising at least one mixer configured to receive the received signal claim 1 , the carrier signal and the local template signal.3. The receiver of claim 2 , wherein the at least one mixer comprises an in-phase mixer and a quadrature-phase mixer.4. The receiver of claim 3 , wherein the in-phase mixer and the quadrature-phase mixer are configured to be activated during each pulse of the plurality of pulses.5. The receiver of claim 3 , wherein the in-phase mixer is configured to subtract the received signal from an in-phase component of the carrier signal so as to generate a first mixed signal claim 3 , and wherein the quadrature-phase mixer is configured to subtract the received signal from a quadrature-phase component of the carrier signal so as to generate a second mixed signal.6 ...

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Номер записи: 86

12-12-2013 дата публикации

RECEIVING CIRCUIT, CLOCK RECOVERY CIRCUIT, AND COMMUNICATION SYSTEM

Номер: US20130329776A1

Автор: Yamaguchi Kouichi

Принадлежит:

High data-rate magnetic coupling communication is realized with a small circuit size without sacrificing the communication distance. 1. A receiving circuit which receives , via a transmission path formed by magnetic coupling of inductors at a transmission side and a receiving side , a signal corresponding to transmission data having a data rate equal to or higher than a self-resonant frequency of the inductors , the receiving circuit comprising:a received data acquisition circuit which performs a decision-feedback equalization process on the received signal to obtain a shaped signal and, according to a sampling clock, performs sampling of the shaped signal with a same sampling rate as the data rate to obtain data samples; anda clock recovery circuit which corrects the sampling clock so that the received data acquisition circuit performs sampling at a correct sampling timing,wherein the clock recovery circuit includes:a midpoint sample acquisition circuit which performs sampling of the received signal at an intermediate timing of the sampling timing of the received data acquisition circuit to obtain a midpoint sample; anda phase adjustment circuit which adjusts a phase of the sampling clock, based on the data samples and the midpoint sample.2. The receiving circuit according to claim 1 ,wherein the phase adjustment circuit performs the adjustment, when the successive data samples form a predetermined pattern, based on the midpoint sample obtained at the intermediate timing immediately after a sampling timing of a last data sample of the data samples.3. The receiving circuit according to claim 2 ,wherein the predetermined pattern is a rising pattern or a falling pattern,wherein the rising pattern is a pattern such thatwhen the sampling clock is correct,a voltage of the received signal rises in a direction toward a positive side from a negative side within a period from the sampling timing of a last data sample of the data samples forming the pattern to a next sampling ...

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Номер записи: 87

12-12-2013 дата публикации

SYSTEMS AND METHODS FOR IMPLEMENTING IMPROVED FREQUENCY ESTIMATION

Номер: US20130329815A1

Автор: Azizi Shahrnaz, Kenney Thomas J., Perahia Eldad

Принадлежит:

A system and method are provided for implementing improved frequency estimation for wireless communications in support of a broader set of use cases including outdoor use cases and use cases that involve lower power transmissions with reduced signal-to-noise ratios for receivers particularly in systems configured according to the pending IEEE 802.11 ah standard. These systems and methods provide greatly improved frequency estimation over that prescribed for devices operating according other IEEE 802.11 standards, including the frequency estimator conventionally used in systems operated according to the IEEE 802.11n standards, and the proposed frequency estimator specified for IEEE 802.11ac systems. The disclosed techniques facilitate improved frequency estimation schemes that reuse of a short training field (STF) stored in memory, employ joint STF-long training field (LTF) estimation, use portions of a guard interval (GI), and create of multiple-phase estimates, with different symbol separation to improve a signal-to-noise ratio of the frequency estimate. 1. A wireless communication system , comprising:a receiving device that receives a wireless signal including a packet preamble structure having a partially periodic training component; anda frequency estimator that computes a plurality of component frequency estimates according to portions of the partially periodic training component, that aggregates the plurality of component frequency estimates to determine an overall frequency estimate for the received wireless signal, and that adjusts the receiving device according to the overall frequency estimate.2. The system of claim 1 , the partially periodic training component being a long training field consisting of four symbols.3. The system of claim 2 , the four symbols comprising two symbols that are together constituted of a double guard interval and a pair of long training sequences and two symbols that are each constituted of a single guard interval and a long ...

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Номер записи: 88

12-12-2013 дата публикации

Method, Radio Unit and Radio Base Station for Adjusting Thresholds for Crest Factor Reduction

Номер: US20130329819A1

Автор: Gu Tao

Принадлежит: TELEFONAKTIEBOLAGET L M ERICSSON (PUBL)

The present invention relates to clipping thresholds adjustment for Crest Factor Reduction CFR in a radio unit, wherein the radio unit comprises one or more clipping stages that apply respective clipping thresholds to clip input signals, comprising: determining a target threshold for the clipping stages based on a target PAR and the amplitudes or powers of the input signals, estimating the direction in which original PAR of the input signals changes by comparing amplitudes of the clipped signals from the clipping stages with the target threshold, and adjusting the clipping thresholds based on the estimated direction. The present invention also relates to dynamic stage control. With the present invention, clipping thresholds and clipping stages are adaptively changes with dynamic original PAR of input signals and the efficiency of power amplifier is increased with a low implementation cost. 122-. (canceled)23. A method for adjusting clipping thresholds for Crest Factor Reduction (CFR) in a radio unit , wherein the radio unit comprises one or more clipping stages that apply respective clipping thresholds to clip input signals , the method comprising:determining a target threshold for the clipping stages based on a target Peak to Average power Ratio (PAR) and amplitudes or powers of the input signals;estimating a direction in which an original PAR of the input signals changes by comparing amplitudes of the clipped signals from the clipping stages with the target threshold;adjusting the clipping thresholds based on the estimated direction.24. The method of :wherein the estimating comprises generating a first count value by counting a number of clipped samples of the clipped signals of which amplitudes exceed the target threshold for a counting time period;wherein in response to the first count value being higher than a predetermined upper limit, the direction is estimated as increase;wherein in response to the first count value being lower than a predetermined lower ...

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Номер записи: 89

19-12-2013 дата публикации

ITERATIVE EQUALIZATION WITH NON-LINEAR SOFT INTERFERENCE CANCELLATION IN NON-LINEAR SATELLITE CHANNELS

Номер: US20130336377A1

Автор: Fitz Michael P., Liu Daniel N.

Принадлежит: Northrop Grumman Systems Corporation

A method for removing distortions in a transmitted signal transmitted by a high power amplifier in a satellite communications system. The method characterizes the high power amplifier to define a series of Volterra coefficients and uses those coefficients in an equalizer in a receiver in the communications system to remove the distortions. The equalizer is a non-linear soft interference cancellation and minimum mean square error equalizer that employs three processing operations including parallel soft interference cancellation, minimum mean square error filtering and a priori log-likelihood ratio calculations. 1. A method for removing distortions in an actual transmitted signal transmitted by a high power amplifier , said actual transmitted signal including bits , said method comprising:providing a model of the high power amplifier that generates a reproduced transmitted signal of the actual transmitted signal;defining a series of Volterra coefficients from the reproduced transmitted signal using a Volterra model;receiving the actual transmitted signal in a receiver; andprocessing the actual transmitted signal in an equalizer in the receiver to generate a digital signal including the bits, wherein processing the actual transmitted signal in the equalizer includes providing parallel soft interference cancellation of the actual transmitted signal that cancels both linear and non-linear interference for each symbol of interest in the actual transmitted signal, filtering the actual transmitted signal after the interference cancellation using a minimum mean square error filter that employs the Volterra coefficients to provide equalizer coefficients, and using the equalizer coefficients to generate a new extrinsic log-likelihood ratio (LLR) of the bits in the actual transmitted signal.2. The method according to wherein processing the actual transmitted signal in an equalizer includes providing the new extrinsic LLR of the bits to an outer channel decoder that decodes the ...

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Номер записи: 90

19-12-2013 дата публикации

Efficient method to overcome frequency errors within four time slots

Номер: US20130337759A1

Автор: Ilan Sutskover, Rotem Avivi

Принадлежит: Intel Corp

A system and a method in which a first frequency correction is determined for a frequency of a local oscillator with respect to a frequency of a first time slot of a received signal. The first frequency correction is applied to adjust the frequency of the local oscillator. A second frequency correction is determined for the frequency of the local oscillator with respect to a frequency of a second time slot of the received signal. The second frequency correction is applied to adjust the frequency of the local oscillator. A third frequency correction is determined for the frequency of the local oscillator with respect to a frequency of a third time slot and a fourth time slot of the received signal, and the third frequency correction is applied to adjust the frequency of the local oscillator.

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Номер записи: 91

26-12-2013 дата публикации

Multi-Mode Transmitter for Highly-Spectrally-Efficient Communications

Номер: US20130343485A1

Автор: Eliaz Amir

Принадлежит: MagnaCom Ltd.

A transmitter may comprise a symbol mapping circuit that is configurable to operate in at least two configurations, wherein a first of the configurations of the symbol mapping circuit uses a first symbol constellation and a second of the configurations of the symbol mapping circuit uses a second symbol constellation. The transmitter may also comprise a pulse shaping circuit that is configurable to operate in at least two configurations, wherein a first of the configurations of the pulse shaping circuit uses a first set of filter taps and a second of the configurations of the pulse shaping circuit uses a second set of filter taps. The first set of filter taps may correspond to a root raised cosine (RRC) filter and the second set of filter taps corresponds to a partial response filter. 1. (canceled)2. A system comprising: while said transmitter is configured into a first of said modes, said transmitter is configured to use a pulse shaping filter configured as a near zero positive ISI filter;', 'while said transmitter is configured into in a second of said modes, said transmitter is configured to generate an inter-symbol correlated (ISC) signal;', 'said transmitter comprises an amplifier;', 'while said transmitter is configured into a first of said modes, a first amount of power back-off is used by said amplifier; and', 'while said transmitter is configured into a second of said modes, a second amount of power back-off is used by said amplifier., 'a transmitter configurable to operate in at least two modes, wherein3. A system comprising: while said transmitter is configured into a first of said modes, said transmitter is configured to use a pulse shaping filter configured as a near zero positive ISI filter;', 'while said transmitter is configured into in a second of said modes, said transmitter is configured to generate an inter-symbol correlated (ISC) signal;', 'said transmitter comprises an amplifier; and', 'while said transmitter is configured into said second of ...

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Номер записи: 92

26-12-2013 дата публикации

Multi-Mode Receiver for Highly-Spectrally-Efficient Communications

Номер: US20130343487A1

Автор: Eliaz Amir

Принадлежит: MagnaCom Ltd.

A receiver may be dynamically configurable, during run-time, into a plurality of modes of operation. In a first mode of operation the receiver may demodulate received signals having relative low inter-symbol correlation using a near zero ISI filter and symbol slicing. In a second mode of operation the receiver may demodulate received signals having relatively high inter-symbol correlation using an input filter configured to achieve a desired total partial response and a sequence estimation algorithm. 1. A system comprising: while said receiver is configured into a first of said modes, an input filter of said receiver is configured as a near zero positive ISI filter; and', 'while said receiver is configured into in a second of said modes, said input filter of said receiver is configured for reception of an inter-symbol correlated (ISC) signal., 'a receiver configurable to operate in at least two modes, wherein2. The system of claim 1 , wherein:while said receiver is configured into in a second of said modes, said input filter is configured based on desired total partial response arising from a combination of said input filter and a pulse shaping filter of a transmitter from which communications are to be received by said receiver.3. The system of claim 1 , comprising a gain circuit claim 1 , wherein:while said receiver is configured into a first of said modes, said gain circuit is configured to have a first amount of power back-off; andwhile said receiver is configured into a second of said modes, said gain circuit is configured to have a second amount of power back-off.4. The system of claim 1 , comprising a gain circuit claim 1 , wherein:while said receiver is configured into said second of said modes, said gain circuit is dynamically configured based on noise figure of said receiver.5. The system of claim 4 , wherein:said dynamic configuration of said gain circuit dynamically varies a linearity of said receiver to optimize a noise figure in said receiver.6. The ...

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Номер записи: 93

26-12-2013 дата публикации

Controllable Frequency Offset for Inphase and Quadrature (IQ) Imbalance Estimation

Номер: US20130343492A1

Автор: Park Chester, Svensson Jim

Принадлежит: TELEFONAKTIEBOLAGET L.M ERICSSON (PUBL)

Embodiments of user equipment and methods for determining IQ imbalance parameters are described. In some embodiments, a method for determining in-phase (I) and Quadrature (Q) imbalance (IQ imbalance) parameters based on a known signal in a dual-carrier receiver using at least one controllable frequency offset includes receiving a known signal modulated onto a first radio frequency (RF) carrier frequency and a second RF carrier frequency different than the first RF carrier frequency. The known signal is downconverted to a baseband signal for the carriers by conversion from the respective RF carrier frequencies to an intermediate frequency (IF) using a common RF local oscillator (LO) and by further conversion from IF to baseband using carrier specific IF LOs, where a controllable frequency offset is used. Any controllable frequency offset is removed from the baseband signal for the first and second carriers to produce representations of the received signals. 1. A method for determining in-phase (I) and Quadrature (Q) imbalance (IQ imbalance) parameters based on a known signal in a dual-carrier receiver using at least one controllable frequency offset , the method comprising:receiving a known signal modulated onto a first radio frequency (RF) carrier frequency and a second RF carrier frequency different than the first RF carrier frequency;downconverting the known signal to a baseband signal for the first and second carriers by conversion from the respective RF carrier frequencies to an intermediate frequency (IF) using a common RF local oscillator (LO) and by further conversion from IF to baseband using carrier specific IF LOs, wherein as a controllable frequency offset is used as a part of the conversion from at least one of RF to IF and IF to baseband through the LOs;removing any controllable frequency offset from the baseband signal for the first and second carriers to produce representations of the received signals of the first and second carriers; andderiving IQ ...

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Номер записи: 94

09-01-2014 дата публикации

MODULATION CODING SCHEME SELECTION FOR RESPONSE FRAMES IN CASE OF TRANSMIT POWER IMBALANCE

Номер: US20140010158A1

Автор: Jafarian Amin, Merlin Simone

Принадлежит:

Certain aspects of the present disclosure relate to a technique for selecting modulation coding schemes (MCS). In some aspects, the MCS is selected based on a characteristic of an electronic device and the MCS of a transmitter. In some aspects, the MCS is selected based on a power imbalance between an access point and a user terminal. 1. A method for communicating in a wireless network by an electronic device , the method comprising:receiving data identifying a first modulation coding scheme from a transmitter;selecting a second modulation coding scheme based on a characteristic of the electronic device including the first modulation coding scheme, wherein information identifying the second modulation coding scheme is a predetermined quantity lower than the first modulation coding scheme; andtransmitting data identifying the second modulation coding scheme.2. The method of claim 1 , wherein receiving data identifying a first modulation coding scheme comprises:receiving an indication of transmit power of the transmitter in a field element at a time of association; andwherein the predetermined quantity is a function of a difference between the indicated transmit power of the transmitter and a transmit power of the electronic device.3. The method of claim 1 , wherein the electronic device receives the predetermined quantity from the transmitter.4. The method of claim 3 , wherein the electronic device receives the predetermined quantity in an association request frame.5. The method of claim 3 , wherein the electronic device receives the predetermined quantity in a management frame sent after association.6. The method of claim 1 , wherein the electronic device provides the predetermined quantity.7. The method of claim 1 , wherein the second modulation coding scheme does not exceed a predetermined quantity.8. The method of wherein the predetermined quantity is a datarate or modulation code scheme order.9. The method of claim 1 , wherein receiving data identifying a first ...

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Номер записи: 95

09-01-2014 дата публикации

TRANSMISSION METHOD, TRANSMISSION APPARATUS AND RECEPTION APPARATUS

Номер: US20140010331A1

Автор: Matsuoka Akihiko, MURAKAMI Yutaka, ORIHASHI Masayuki

Принадлежит: Panasonic Corporation

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 ...

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Номер записи: 96

09-01-2014 дата публикации

SYSTEM AND METHOD FOR PROCESS, VOLTAGE, TEMPERATURE (PVT) STABLE DIFFERENTIAL AMPLIFIER TRANSFER FUNCTION

Номер: US20140010333A1

Автор: COHEN Hanan

Принадлежит: Applied Micro Circuits Corporation

A method is provided for process, voltage, temperature (PVT) stable transfer function calibration in a differential amplifier. The gain resistors of a differential amplifier are initially selected to achieve a flat amplitude transfer function in the first frequency band. After calibration, the degeneration capacitor is connected and tuned until a peaked amplitude transfer function is measured, which is resistant to variations in PVT. As an alternative, the degeneration capacitor is not disconnected during initial calibration. Then, the gain resistors and the degeneration capacitor values are selectively adjusted until the first peaked amplitude transfer function is obtained. The peaked amplitude transfer function remains even more stable to variations in PVT than the flat amplitude calibration method. 120-. (canceled)21. A clock and data recovery (CDR) device comprising:a receiver comprising a differential amplifier, wherein the differential amplifier comprises a plurality of variable gain resistors, a variable degeneration resistor, and a variable degeneration capacitor, and wherein the receiver is operable to generate an output signal; andan initialization module operable to disconnect the variable regeneration capacitor in response to receiving a start-up signal, and wherein the initialization module is further operable to selectively adjust values for the plurality of variable gain resistors and the variable degeneration resistor until the output signal of the differential amplifier comprises a first frequency band with a flat transfer function.22. The CDR device of claim 21 , wherein the differential amplifier further comprises a first field effect transistor (FET) and a second FET claim 21 , wherein a first variable gain resistor is coupled to the first FET and a second variable gain resistor is coupled to the second FET claim 21 , and wherein the variable degeneration resistor is coupled between the first FET and the second FET.23. The CDR device of further ...

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Номер записи: 97

16-01-2014 дата публикации

HDMI SIGNAL ADJUSTING METHOD, HDMI SIGNAL RECEIVING APPARATUS, HDMI SIGNAL TRANSMITTING APPARATUS, AND HDMI SIGNAL PROCESSING SYSTEM

Номер: US20140016684A1

Автор: CHA Ki-sung, HONG Seung-se, JEON Hyoung-woo, LIM Jun-ho, OH Sung-bo, SEO Young-jo

Принадлежит:

An HDMI signal adjusting method is provided. A method for adjusting an HDMI signal of a high definition multimedia interface (HDMI) signal receiving apparatus includes: setting an equalizer gain for an HDMI signal, receiving an HDMI signal which is adjusted according to signal adjustment information set by an HDMI signal transmitting apparatus from the HDMI signal transmitting apparatus, signal-processing the received HDMI signal according to the set equalizer gain, detecting an error rate of the signal-processed HDMI signal, and transmitting signal adjustment information corresponding to an HDMI signal having a lowest error rate from among a plurality of the signal-processed HDMI signals corresponding to a plurality of different combinations of the equalizer gain and the signal adjustment information to the HDMI signal transmitting apparatus. 1. A method for adjusting a high definition multimedia interface (HDMI) signal of an HDMI signal receiving apparatus , the method comprising:setting an equalizer gain for an HDMI signal;receiving an HDMI signal which is adjusted according to signal adjustment information set by an HDMI signal transmitting apparatus from the HDMI signal transmitting apparatus;signal-processing the received HDMI signal according to the set equalizer gain;detecting an error rate of the signal-processed HDMI signal; andtransmitting signal adjustment information corresponding to an HDMI signal having a lowest error rate from among a plurality of the signal-processed HDMI signals corresponding to a plurality of different combinations of the equalizer gain and the signal adjustment information to the HDMI signal transmitting apparatus.2. The method as claimed in claim 1 , wherein the setting the equalizer gain comprises setting the equalizer gain by changing the equalizer gain by adjusting an equalizer gain level in sequence.3. The method as claimed in claim 1 , wherein the HDMI signal is adjusted by changing at least one of a pre-emphasis gain and a ...

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Номер записи: 98

16-01-2014 дата публикации

APPARATUS AND METHOD FOR IMPROVING THE PERFORMANCE OF A LINEAR EQUALIZER WITH MULTIPLE RECEIVE ANTENNAS

Номер: US20140016689A1

Автор: Chizgi Nate, Dua Aditya

Принадлежит: QUALCOMM INCORPORATED

Disclosed are methods and apparatus for initializing an equalizer in a diversity receiver. In one aspect, the initialization includes estimating a channel impulse response (CIR) for each receiver chain of the diversity receiver; determining noise power estimates for each receiver chain based on the CIRs; and adaptively adjusting equalizer taps of each receiver chain based on the noise power estimates. In one aspect, the adaptive adjusting of the equalizer taps is based on scaling the CIR and covariance metrics for the receiver chain with higher noise power by a scale factor determined from the noise power estimates. In another aspect, the adaptive adjusting of the equalizer taps is based adaptive conditioning on the diagonal of the covariance matrix. 1. A method for initializing an equalizer in a diversity receiver , the method comprising:estimating a channel impulse response (CIR) for each receiver chain of the diversity receiver;determining noise power estimates for each receiver chain based on the CIRs;adaptively adjusting equalizer taps of each receiver chain based on the noise power estimates.2. The method of claim 1 , wherein adaptively adjusting equalizer taps of each receiver chain of the diversity receiver further comprises:determining channel estimates for each receiver chain of the diversity receiver;computing a ratio of the noise power estimates of the receiver chains;computing a scaling factor as a function of the ratio of noise power estimates;identifying a receiver chain with the higher noise power estimate;scaling channel estimates for the receiver chain with the higher noise power using the computed scaling factor; andcomputing equalizer taps of each receiver chain based on the scaled channel estimates.3. The method of claim 2 , wherein determining noise power estimates for each RF receiver chain based on the CIRs further includes:determining post-AGC noise power estimates for each RF receiver chain.4. The method of claim 2 , wherein scaling channel ...

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Номер записи: 99

16-01-2014 дата публикации

TRANSMISSION APPARATUS FOR A WIRELESS DEVICE

Номер: US20140016719A1

Автор: Manku Tajinder

Принадлежит:

A transmission apparatus for a wireless device, comprising: an antenna for receiving an original signal and for backscattering a modulated signal containing information from the wireless device; a variable impedance coupled to the antenna, the variable impedance having an impedance value; and, a decoder coupled to the variable impedance for modulating the impedance value, and thereby a backscattering coefficient for the antenna, in accordance with the information to generate the modulated signal. 1. A transmission apparatus for a wireless device , comprising:an antenna for receiving an original signal and for backscattering a modulated signal containing information from the wireless device;a variable impedance coupled to the antenna, the variable impedance having an impedance value; and,a decoder coupled to the variable impedance for modulating the impedance value, and thereby a backscattering coefficient for the antenna, in accordance with the information to generate the modulated signal.2. The transmission apparatus of wherein the variable impedance is coupled in series with the antenna.3. The transmission apparatus of wherein the wireless device is powered by energy from the original signal.4. The transmission apparatus of wherein the variable impedance includes an array of impedances and respective switches.5. The transmission apparatus of wherein the decoder includes a backscattering coefficient to impedance value decoder.6. The transmission apparatus of wherein the information is an N-bit digital waveform.7. The transmission apparatus of wherein the N-bit digital waveform is applied to the decoder to produce a control signal for the variable impedance that is related to the N-bit digital waveform.8. The transmission apparatus of wherein a change in the impedance value backscatters the original signal to produce the modulated signal claim 7 , the modulated signal being a frequency offset form of the N-bit digital waveform.9. The transmission apparatus of ...

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Номер записи: 100