Combined Beam Alignment and Power Allocation for NOMA-Empowered mmWave Communications

Millimeter-wave communications have recently attracted significant interest in future wireless networks regarding its wide bandwidth that achieves high data rates. However, the major challenge lies in the beam alignment problem that may induce a substantial loss in the received power, notably when narrow beams are employed. Therefore, this paper jointly addresses the problem of beam alignment and power allocation in a non-orthogonal multiple access (NOMA) mmWave system. Unlike the conventional orthogonal multiple access (OMA), we study the case where two users are joined for NOMA transmission. Next, to mitigate this combined issue, we propose an optimization formulation owing to maximize the sum rate. We compare two types of antennas: sectorized and lemniscate antenna patterns under NOMA and OMA schemes. Simulation results prove the performance of NOMA-lemniscate based beam alignment and power allocation scheme compared to the conventional OMA scheme.