Max-Min Fair Precoder Design and Power Allocation for MU-MIMO NOMA

In this correspondence, transmit precoders and their power allocation coefficients are designed jointly for a downlink non-orthogonal multiple access (NOMA) wireless communication system. The objective is to provide max-min fairness (MMF) among the strongest users in each group, while maintaining minimum target rates all other users. proposed solutions respectively based on semi-definite relaxation (SDR) successive convex approximation (SCA) mean square error (MMSE) approaches. For latter approach, simplification also suggested lower complexity. It shown that rate-splitting (RS) has best MMF rates, low-complexity MMSE approach least Moreover, SDR/SCA offers an excellent tradeoff between two.