Mobile communication 3G/4G (third generation/fourth generation) electric wave propagation loss NPL (noise-pollution level) model under shade of street trees and network optimization method

The invention discloses a mobile communication 3G/4G (third generation/fourth generation) electric wave propagation loss NPL (noise-pollution level) model under the shade of street trees and a network optimization method; the mobile communication 3G/4G electric wave propagation loss NPL model under the shade of the street trees comprises four types of street trees, the first, second and third types of street trees are thick with leaves, and can greatly absorb energy of electric waves; the fourth type of street tree is thin with leaves, about 5 m in height and about 5 years old, and can absorb less energy of electric waves; the invention further relates to a network optimization method of the mobile communication 3G/4G electric wave propagation loss NPL model under the shade of the street trees, comprising the following steps: (1) setting a base station distance, wherein a base station is inappropriate to close to the street trees, an incident angle can be controlled between 10-30 degrees ...

Quantum router for multi-user photon communication network and routing method thereof

The invention discloses a quantum router for a photon communication network, which mainly solves the problems that the conventional router has no calling/connection management and routing processing functions and that user equipment is complex. The quantum router consists of a call/connection control module, a routing control module, a routing information data management module, a link resource management module, a network communication module, an interface module and an optical cross connector, wherein the call/connection control module verifies the legality and validity of a user; the routing control module is used for establishing routing; the routing information data management module establishes and maintains a routing table; the link resource management module maintains link resources; and the network communication module receives and transmits control information. Connection is established if a certain link and a called user are idle, a control message of an optical switch is transmitted ...

Network measuring system structure and realizing method thereof

Multiple-tag identifying method of radio-frequency identifying network

The invention discloses a multiple-tag identifying method of a radio-frequency identifying network. The method comprises the following steps that a reader finishes initialization and selects tags in the effective field; the reader sends a tag access instruction or a re-sending instruction to receive the tags; the tags reply in certain probability according to the information in the access instruction; the reader receives and treats the tag replying information, if the reader correctly receives the tag replying information or the received information is empty, the reception of the next time slot is transferred, the tag replying probability information and the tag replaying confirm information in the access instruction are refreshed, and the tag access instruction is sent; if the reader detects the conflict among multiple tags in the pre-set time slot, the reader sends the re-sending instruction at the time slot or receives the tags in the next time slot; and when the reader sends the access ...

Multiple-tag identifying method of radio-frequency identifying network

The invention discloses a multiple-tag identifying method of a radio-frequency identifying network. The method comprises the following steps that a reader finishes initialization and selects tags in the effective field; the reader sends a tag access instruction or a re-sending instruction to receive the tags; the tags reply in certain probability according to the information in the access instruction; the reader receives and treats the tag replying information, if the reader correctly receives the tag replying information or the received information is empty, the reception of the next time slot is transferred, the tag replying probability information and the tag replaying confirm information in the access instruction are refreshed, and the tag access instruction is sent; if the reader detects the conflict among multiple tags in the pre-set time slot, the reader sends the re-sending instruction at the time slot or receives the tags in the next time slot; and when the reader sends the access ...

Heralded single-photon source generation device for quantum communication

The invention discloses a heralded single-photon source generation device for quantum communication, comprising: a clock module, a control unit, a controllable electric switch module, an electric narrow-pulse source module, an amplification module, a semiconductor laser, a numerical control variable optical attenuator, an optical coupler, an optical power detection module and a fixed optical attenuator; the optical power detection module receives a laser pulse from the optical coupler, and measures size of the laser pulse optical power; the control unit determines amount of attenuation of the variable optical attenuator according to the power detected by the optical power detection module, and transmits a control instruction to the numerical control variable optical attenuator to enable the same to reach appointed amount of attenuation. The heralded single-photon source generation device has the advantages of steady output, low complexity and easy control, and can be used for a quantum ...