Lightweight Digital Self-Interference Cancellation

As has been known, co-frequency co-time full-duplex transmission can double the bandwidth efficiency of half-duplex by overlapping the transmitted and received signals in frequency and time domains. While, for approaching the theoretical gain of doubling spectral efficiency, the self-interference (SI) should be canceled below the noise power. Toward achieving this goal, we analyze the key role of channel estimation and apply the least squares (LS) method. Then, multipath channel detection (MCD) is proposed to reduce the complexity of the LS algorithm. Simulation results show that the lightweight MCD method achieves the same accuracy as that of the LS method but requires less computational expenditure.