Full-Duplex Device-to-Device Aided Cooperative Non-Orthogonal Multiple Access

TLDR

The study proposes a full‑duplex device‑to‑device aided cooperative NOMA scheme and an adaptive multiple‑access strategy to enhance the outage performance of the weak user in a NOMA pair. Outage probability expressions are derived for the cooperative NOMA scheme, and an adaptive multiple‑access scheme that switches among cooperative NOMA, conventional NOMA, and OMA based on residual self‑interference and link quality is analyzed. Simulation results demonstrate that the cooperative NOMA scheme outperforms conventional NOMA and OMA, and the adaptive multiple‑access scheme further improves outage performance over all compared schemes.

Abstract

This paper presents a full-duplex device-to-device (D2D)-aided cooperative nonorthogonal multiple access (NOMA) scheme to improve the outage performance of the NOMA-weak user in a NOMA user pair, where the NOMA-weak user is helped by the NOMA-strong user with the capability of full-duplex D2D communications. The expressions for the outage probability are derived to characterize the performance of the proposed scheme. The results show that the proposed cooperative NOMA scheme can achieve superior outage performance compared to the conventional NOMA and orthogonal multiple access (OMA). In order to further improve the outage performance, an adaptive multiple access (AMA) scheme is also studied, which dynamically switches between the proposed cooperative NOMA, conventional NOMA, and OMA schemes, according to the level of residual self-interference and the quality of links. The results show that the AMA scheme outperforms the above multiple access schemes in terms of outage performance.