Peking University

Beijing Xinxing Weitong Technology Co., Ltd.

Ye Jin

Tao He

Guocheng Lv

Mingke Dong

Baoji Wang

Aimin Liu

A method for piloting from bypass in a network based on a satellite load platform can unify the influence of distance change and Doppler frequency shift of satellite ground stations in the whole network, and realize accurate quasi synchronization between the clock of the whole network and the clock of the satellite. The method includes transmitting a pilot signal from bypass based on a satellite load platform in a satellite communication system, taking a spaceborne high stability timing clock source as a reference, and transmitting the pilot signal to all downlink beams to provide the pilot signal for all satellite stations covered by the satellite.

Method for piloting from bypass in a network based on satellite load platform

A method for quasi-synchronous code division multiple access based on synchronization clock by piloting can make CDMA operate in quasi-synchronous conditions, so it is suitable for open wireless channels with relay nodes, such as satellite communication systems, and open wireless channels without relay nodes. The method includes: adopting a mode of CDMA spread spectrum transmission to share power resources to transmit signals at multiple transmitting stations in open wireless channels; adopting an external pilot signal to provide synchronization clock for the CDMA signals transmitted by multiple terminal stations in the open wireless channels, eliminating path delay differences from the multiple terminal stations to a relay node or receiving station, and making multi-channel CDMA signals received at the relay node or receiving station clock synchronized and phase aligned. The method can realize the quasi-synchronous reception of multi-channel CDMA signals.

Method for quasi-synchronous code division multiple access based on synchronization clock by piloting

A method for allocating resource and accessing in open wireless channels includes: covering multiple types of user terminal stations in open wireless channels; making dynamic adaptive matching according to comprehensive change factors of a transmitting end and a receiving end in each communication process. The factors of the transmitting end mean that a type and transmitting capacity of a transmitting station are changed, a current state of the wireless channel between the transmitting station and a relay node is changed, a working state of a receiving end of the relay node is changed, and user services to be transmitted are changed; the factors of the receiving end mean that a type and receiving capacity of a receiving station are changed, a current state of the channel from the relay node to the receiving station is changed, and a working state of a transmitting end of the relay node is changed.

Method for allocating resource and accessing in open wireless channels

A method for piloting from bypass in a network with open wireless channels is disclosed. The method includes: 1) selecting a terminal station as a reference in open wireless channels, and sending a pilot signal, in which all or some frequency bands of open wireless channels occupied by the pilot signal are pilot frequency bands, and the proportion of power of the pilot signal to the total power of the pilot frequency bands is 0.1‰-5%; 2) spreading the pilot signal with a spread spectrum code when it is transmitted, and then superimposing on a communication signal in the pilot frequency bands in a low power spectrum signal mode similar with noise; and) providing pilot, carrier wave and clock synchronization, standard timing and indication information for network construction and mutual communication of multiple types of terminal stations in channels by the pilot signal.

Growing community of inventors

Beijing, China

Ye Jin