Digital Assisted Analog Cancellation in Full-Duplex System

In full-duplex wireless communication system, self-interference is an important factor that can affect signal receiving. If the power of self-interference is too large, it affects the receiving of useful information, so the self-interference cancellation should be carried out in the full-duplex system. Self-interference cancellation is generally divided into three different domains: propagation, analog, and digital. A new digital assisted analog cancellation system in full-duplex is examined. The proposed full-duplex system consists of a 4-TAP analog cancellation stage, followed by a sixth-order cancellation algorithm based on LS accounting for the nonlinear distortion of the SI signal. Through simulation experiments, it is found that 50dB of analog cancellation stage and 57dB of digital auxiliary cancellation stage can be realized in 20MHz band, with a total cancellation effect of 107dB, which can meet the actual cancellation requirements.