Antenna Selection in Full-Duplex Cooperative NOMA Systems

TL;DR

This paper explores antenna selection strategies in full-duplex cooperative NOMA systems, deriving analytical expressions for performance metrics and demonstrating near-optimal results compared to optimal schemes.

Contribution

It proposes new antenna selection schemes based on end-to-end SNR for FD cooperative NOMA, with analytical performance analysis and comparison to optimal and random schemes.

Findings

Proposed AS schemes achieve near-optimal sum rate and outage probability.

Closed-form expressions for ergodic sum rate and outage probability are derived.

AS schemes outperform random selection and approach optimal performance.

Abstract

We investigate the problem of antenna selection (AS) in full-duplex (FD) cooperative non-orthogonal multiple access (NOMA) systems, where a multi-antenna FD relay assists transmission from a multi-antenna base station (BS) to a far user, while at the same, the BS transmits to a near user. Specifically, based on the end-to-end signal-to-interference-plus-noise ratio at the near and far users, two AS schemes to select a single transmit antenna at both the BS and the relay, respectively, as well as a single receive antenna at relay are proposed. In order to study the ergodic sum rate and outage probability of these AS schemes, we have derived closed-form expressions assuming Rayleigh fading channels. The sum rate and outage probability of the AS schemes are also compared with the optimum selection scheme that maximizes the performance as well as with a random AS scheme. Our results show that the proposed AS schemes can deliver a near-optimal performance for near and far users, respectively.