Ergodic Rate for Downlink and Uplink NOMA Aided Integrated Sensing and Communication

Abstract

This letter analyzes the ergodic rate of non-orthogonal multiple access (NOMA) aided integrated sensing and communication (ISAC) systems. In the presented system model, a full-duplex base station communicates with downlink and uplink communication users and simultaneously performs mono-static sensing of a target. The performance of this system is evaluated by analytically deriving the closed-form expressions of ergodic rate in the presence and absence of a target. Despite co-channel interferences and the presence of the target, NOMA achieves a significantly better rate, thus improving the system’s performance and making it a suitable technology for ISAC systems. The derived analytical results for a Rayleigh fading are verified and are in exact agreement with Monte-Carlo simulations. Further, more insights have been obtained by comparing the performance results of the considered system model with that of a traditional orthogonal multiple access scheme.