NOMA Inspired Interference Cancellation for Integrated Sensing and Communication

TL;DR

This paper introduces a NOMA-inspired interference cancellation scheme for integrated sensing and communication systems, optimizing signals to improve performance while satisfying rate and interference constraints.

Contribution

It proposes a novel NOMA-inspired interference cancellation method and joint signal optimization framework for ISAC systems, enhancing performance over traditional approaches.

Findings

Outperforms conventional ISAC systems in simulations

Achieves near-ideal performance with effective interference mitigation

Uses successive convex approximation for near-optimal solutions

Abstract

A non-orthogonal multiple access (NOMA) inspired integrated sensing and communication (ISAC) system is investigated. A dual-functional base station (BS) serves multiple communication users while sensing multiple targets, by transmitting the non-orthogonal superposition of the communication and sensing signals. A NOMA inspired interference cancellation scheme is proposed, where part of the dedicated sensing signal is treated as the virtual communication signals to be mitigated at each communication user via successive interference cancellation (SIC). Based on this framework, the transmitted communication and sensing signals are jointly optimized to match the desired sensing beampattern, while satisfying the minimum rate requirement and the SIC condition at the communication users. Then, the formulated non-convex optimization problem is solved by invoking the successive convex approximation (SCA) to obtain a near-optimal solution. The numerical results show the proposed NOMA-inspired ISAC system can achieve better performance than the conventional ISAC system and comparable performance to the ideal ISAC system where all sensing interference is assumed to be removed unconditionally.