User selection for MIMO downlink employing NOMA

Abstract

In this paper, the multiple-input multiple-output (MIMO) downlink communication system employing non-orthogonal multiple access (NOMA) technique is studied. By taking into account the effect of error propagation on signal reception, a user selection algorithm based on distance and spatial correlati on is proposed, with which an appropriate pair of users can be scheduled. Simulation results show that the proposed method can select the optimal NOMA user pairs, increase the number of users that the system can accommodate, while guaranteeing good system's sum-rate performance.