User Grouping and Optimal Random Beamforming in mmWave MIMO-NOMA Transmission Systems

摘要

In this paper, we propose a new method to achieve lower outage probability in millimeter wave (mmWave) Nonorthogonal multiple access (NOMA) systems with multiple-input-multiple-output (MIMO) structure. We introduce a random user grouping with optimal beamforming coefficients to reduce the system overhead for massive connectivity. In this method, we group users in a set of three according to their distances from the base station (BS). Our simulation results demonstrate that the proposed cellular machine-to-machine (M2M) communication scheme with calculated optimal beamforming coefficients exhibits lower outage probability compared to previous works.