Joint Source and Relay Precoding Design for MIMO Two-Way Relay Systems With Transceiver Impairments

Physical transceiver impairments can degrade the performance of wireless communication systems significantly. Although partial impairments can be mitigated by some compensation algorithms, residual impairments still have substantial effects. In this letter, we investigate the joint source/relay precoding design for the multiple-input multiple-output two-way amplify and forward relay systems by considering hardware impairments. Unlike the ideal case, considering the effect of hardware impairments makes the precoding design more challenging. To tackle the problem, we use certain rules of trace operator to convert the original design problem and develop an iterative algorithm to find a local optimal solution. Simulation results show that the system is more sensitive to hardware impairments in the high signal noise ratio regimes and neglect of the residual hardware impairments will deteriorate the system performance significantly.