Spectral efficiency of single cell full-duplex MU-MIMO system based on SLNR precoding

Abstract

Full-duplex (FD) mode systems are key technologies for 5G wireless communication systems due to their ability improving spectral efficiency. The major difficulties of these systems are in mitigating interferences such as multiuser interferences in both channels and self-interference from downlink to uplink. Therefore, it is required to rely on precoding schemes. We propose self-interference plus noise covariance matrix aware signal-to-leakage-and-noise ratio (SLNR) precoding and SLNR precoding for uplink and downlink channels, respectively, to improve spectral efficiency of FD in the Rician fading channel situations. Unlike zero-forcing (ZF) and block diagonalization (BD) precoding schemes, it has tradeoffs between interference and noise, as well simultaneously support multiple number of users and antennas. The problem is formulated as maximizing SLNR to obtain the precoder that optimized the total spectral efficiency of the system. Numerical results confirm that FD outperforms HD for small self-interference channel gain, for increasing number of antennas at the base station and for all Rician parameters.