Relay sharing with DF and AF techniques in NOMA assisted Cognitive Radio Networks

Abstract

This paper investigates the opportunistic sharing of relay for the proposed Non-Orthogonal Multiple Access (NOMA) assisted Cognitive Radio Networks (CRNs). The proposed scheme consists of a base station that communicates the superimposed composite signal to Primary Equipment (PEs) as well as Secondary Equipment (SEs) with/without a relay. This scheme is opportunistically investigated with both Decode-and-Forward (DF) and Amplify-and-Forward (AF) techniques. A cooperative network is formed with a relay to exploit the potential of spectral diversity offered by NOMA. A cooperative-NOMA furnishes significant performance over the non-cooperative NOMA as well as conventional multiple access in the proposed scheme for CRNs. The simulation results reveal that the superior outage probabilities of PEs and SEs under DF and AF techniques for the proposed scheme. The simulation analyses also authenticate that the DF technique provides outstanding outage performance compared to AF technique.