Multiuser Beamforming System with Massive MIMO-NOMA over mmWave Channel

In this paper, massive multiple-input multiple-out (mMIMO) with non-orthogonal multiple access (NOMA) is considered to serve multiple users wirelessly over millimeter wave (mmWave) channels. A base station (BS) with tens of antennas is proposed to provide services to users in the coverage area by applying zero-forcing (ZF) and maximum ratio transmission (MRT) beamforming techniques. The BS first divides the area into clusters that contain only two users via applying a pairing algorithm, then NOMA is applied to the two users by providing different power allocation factors for satisfying user fairness, and depending on users' circumstances. The achievable throughput for each user in the cluster along with the sum-rate provided by the BS are analyzed and evaluated for the two beamforming mechanisms. The results are obtained for different numbers of BS antennas over different combinations of power allocation coefficients. The simulation results reveal the improvement obtained by increasing the antennas in the BS. Additionally, the two beamforming methods introduce similar throughput when the same parameters are considered, with slight outperforming of MRT in the outage portability.