Two policies for wireless non‐orthogonal multiple access systems: System model and performance enhancement of far user

Abstract

SummaryDevice‐to‐device (D2D)‐enabled non‐orthogonal multiple access (NOMA) network is introduced as promising candidate to support massive connectivity and satisfy the high‐throughput demand. In this paper, two schemes are investigated for situations associated with D2D users and interference from traditional cellular users. The base station equipped multiple antennas is designed to exploit higher diversity gain and make full use of spectrum resources with NOMA technique. Especially, performance improvement can be achieved as enabling D2D link and signal reception of the far user (FU) on cell‐edge area. We study two policies related to downlink and uplink of such D2D NOMA system. The simulation results indicate that the improved ergodic capacity and outage performance can be achieved at FU with more antennas at the base station and higher allocated power factor. In addition, the D2D‐enabled NOMA can significantly improve the spectral efficiency.