Weighted-Sum-Rate maximization for bi-directional full-duplex MIMO systems

We consider a full-duplex bi-directional communication system between two nodes that suffer from self-interference, where the nodes are equipped with multiple antennas and instantaneous channel state information (CSI) at the nodes is imperfect. We focus on the effect of the residual self-interference due to channel estimation errors and limited dynamic ranges of the transmitters and receivers. We consider the transmit filter design for Weighted Sum-Rate (WSR) maximization problem subject to total power constraint of the full-duplex system. Based on the relationship between WSR and Weighted Minimum Mean Square Error (WMMSE) problems for bi-directional full-duplex systems, we propose a low complexity alternating algorithm which converges to a local WSR optimum point. This algorithm exploits both spatial and temporal freedoms of the source co-variance matrices of the multiple-input multiple-output (MIMO) links between the nodes to achieve higher WSR.