Sensing and Mitigation of Far-Field Self-Interference for Full-Duplex MIMO Systems

This paper aims to investigate the isolated effect of the far-field self-interference (SI) for full-duplex MIMO communications. It is shown that the far-field SI is effective only when the scatterers are close to the users. Due to this observation, an SI detector and delay estimator mechanism is proposed for a simpler operation. Additionally, two SI mitigation approaches are compared, namely SI cancellation and spatial SI suppression. Various methods are proposed and examined using SI channel estimate or scatterer angle. It is shown that both approaches can reach SI-free performance given a proper design.