Precoding for Full-Duplex Multiuser MIMO Systems Using Duality

We propose a full-duplex (FD) multiuser multipleinput multiple-output (MU-MIMO) precoding scheme to support the data transmission and self-interference (SI) cancellation simultaneously, by using the transceiver structure. In order to increase the dimensionality at the transmitter, the FD precoding scheme makes use of auxiliary paths, which have constant gains. The FD precoder design takes advantage of the increased dimensionality by jointly preprocessing the transmit signals for an effective trade-off between the forward channel beamforming and the SI suppression. From the numerical result, it can be shown that the proposed FD precoder improves the average sum rate of conventional FD network by setting the proper gains of auxiliary paths to deal with SI.