Full-duplex transceiver in flat fading environment and method for canceling self-interference

Abstract

The invention discloses a full-duplex transceiver in a flat fading environment and a method for canceling self-interference. The method includes dividing received signals by a coupler to obtain a channel I of signals and a channel Q of signals at a receiving end; respectively transmitting the channel I of signals and the channel Q of signals into a channel I receiving channel and a channel Q receiving channels which are structurally symmetrical with each other; canceling the self-interference in a simulated manner in the receiving channels by the aid of multipliers, adders and a radiofrequency interference reconstruction module; digitally canceling the self-interference at the rear end via a digital cancellation unit; transmitting delay estimation parameters and channel estimation parameters to a delay module, the radiofrequency interference reconstruction module and the digital cancellation unit; circularly canceling the self-interference until the optimal cancellation effect is realized. Phase difference between the channel I of signals and the channel Q of signals is 90 degrees. The delay estimation parameters and the channel estimation parameters are generated by a channel / delay estimation unit. The full-duplex transceiver and the method have the advantages that the complexity of the structure of the transceiver can be effectively decreased by the aid of self-mixing and zero-intermediate-frequency technologies, the cost can be saved, and the size of the full-duplex transceiver can be reduced; requirements of self-interference signals on the precision of delay devices can be greatly reduced, and the devices can be selected conveniently and can be implemented easily; the receiving channels are independent from each other, are structurally symmetrical with each other and can be integrated easily.

Description

Technical field [0001] The invention relates to a method for removing interference in the field of wireless communication, in particular to a full-duplex transceiver and a self-interference cancellation method in a flat fading environment. Background technique [0002] Currently, actual wireless communication systems adopt TDD (Time Division Duplexing) or FDD (Frequency Division Duplexing) duplex modes. TDD's duplex system uses the same frequency but different time slots to transmit data, thereby isolating interference between uplink and downlink. The duplex system of FDD uses the same time slot but different frequencies to transmit data, thereby isolating interference between uplink and downlink. These two duplex methods sacrifice time resources and frequency resources respectively in the process of isolating the uplink and the downlink, resulting in low spectrum utilization. If the same frequency is used to transmit and receive wireless signals at the same time, the Co-freque...

AI Technical Summary

Problems solved by technology

[0010] (2) The above-mentioned second self-interference radio frequency cancellation method needs to use a large number of time delay, gain and phase shift devices, the structure is complex, and when the carrier frequency completes the addition and cancellation, it is highly sensitive to the time delay error The nature of the delay device must have a very high adjustment accuracy

Images