Full-half duplex mixed strategy for capacity maximisation in MIMO interference channels

Existing wireless channel Multiple-Input Multiple-Output (MIMO) interference models demonstrate that full duplex communication in a k-link MIMO system suffers from both self-interference and inter-user interference [1]. However, the fact that nodes exchange information simultaneously (Transmission and reception activities) in a bi-directional manner on each of the k considered links; comes with considerable potential gain in terms of channel capacity. On the other hand, halfduplex communication between the k MIMO links comes with the advantage that it does not suffer from self interference. Half duplex MIMO communication however comes with the drawback that it only achieves single link channel capacity. It also can still result in inter-user interference. This paper proposes a mixed strategy which takes advantage of the Full-duplex MIMO capacity gain while reducing self-interference by tapping into the Half-duplex potential and also reducing inter-user interference by interleaving Full-duplex and Half-duplex communications on the k MIMO links. This is done by designing optimum transmitter and receive filters for Weighted Sum Rate (WSR) maximisation using the Rosen´s gradient projection method. After proper modeling and MATLAB simulation, the obtained results show that the Full-Half duplex Mixed strategy enhances the overall channel capacity as compared to the k-link MIMO Full-duplex WSR maximisation approach.