Channel estimation method of full-duplex relay system based on Chu sequence

Abstract

The invention belongs to the technical field of wireless communication, and discloses a channel estimation method of a full-duplex relay system based on a Chu sequence. The method comprises: using a non-blind estimation algorithm, using a Chu sequence and an OFDM symbol as sending data, after channel transmission, the received Chu sequence and the Chu sequence of a sending end being subjected to cross-correlation at a receiving end, and a cross-correlation value obtained by the received Chu sequence and the Chu sequence of the sending end being an impulse response estimation value of a channel; carrying out convolution on the estimated channel value and the Chu sequence of the sending end to obtain a value which is a reconstructed signal; and subtracting the received signal from the reconstructed signal, and performing self-interference elimination. The method starts from two aspects of theoretical simulation and USRP practical simulation, uses the Chu sequence as a training sequence to estimate the same-time same-frequency full duplex relay loop channel, generates a reconstructed signal according to the estimated self-interference channel information, and achieves the offset of the self-interference signal. The transmitting end and the receiving end perform transmission by using two USRPs, and the relay equipment performs simulation by using an amplification forwarding protocol.

Description

technical field [0001] The invention belongs to the technical field of wireless communication, in particular to a channel estimation method of a Chu sequence-based full-duplex relay system. Background technique [0002] At present, the closest existing technology: there is currently a technology using m-sequences for channel estimation. m-sequences are easy to generate and have relatively good autocorrelation characteristics, but the cross-correlation characteristics are not ideal. Using the estimation method based on the Chu sequence, a lower peak-to-average ratio, good cross-correlation properties, and enhanced synchronization accuracy can be obtained. With the development of science and technology, the principles and technologies of modern communication have been rapidly improved, and the continuous development of high-speed communication facilities and communication methods has made people's lives more comfortable and convenient. However, the exponential growth of globa...

AI Technical Summary

Problems solved by technology

[0016] To sum up, the problems existing in the existing technology are: the current full-duplex relay system transmits and receives at the same frequency at the same time, the power of the transmitted signal is much greater than that of the received signal, and the transmitted signal of the device itself interferes with the received signal

This makes the device's own sending signal and the ideal sending signal enter the receiving end together, and the ideal receiving signal cannot be demodulated

[0017] The difficulty of solving the above technical problems: In the full-duplex relay communication system, there is a strong self-interference signal, and the passive cancellation method can be used to eliminate the self-interference, but the passive cancellation method is not enough for the transmitter and the receiver. If the terminal is effectively isolated, it is still necessary to adopt the method of active elimination, the digital domain to eliminate interference and the analog domain to eliminate interference

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