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arXiv · 2511.00721

Fairness-Aware Secure Communication in ISAC Systems with STAR-RIS and RSMA

Thanh Nha To·Hoang Lai Pham·Quynh Nguyen Thi·Tuan Anh Pham·Le Thanh Bang
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Abstract

In this paper, we investigate the integration of simultaneously transmitting and reflecting reconfigurable intelligent surfaces (STAR-RIS) with rate-splitting multiple access (RSMA) for improving physical layer security (PLS) in integrated sensing and communication (ISAC) systems. Specifically, we consider a multi-user, multi-sensing target scenario, where each sensing target is treated as a potential eavesdropper, reflecting realistic deployment conditions. To enable fairness-aware secure communication among users while maintaining sensing performance, we formulate a joint optimization problem that designs the base station beamforming vectors and STAR-RIS coefficients, aiming to maximize the minimum secrecy rate under a minimum beampattern gain constraint. To solve the resulting non-convex problem, we propose an efficient algorithm based on alternating optimization (AO) and the majorization-minimization (MM) method. Simulation results verify the fast convergence of the proposed algorithm and demonstrate significant improvements in secure communication performance.

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Thanh Nha To, Hoang Lai Pham, Quynh Nguyen Thi, Tuan Anh Pham, Le Thanh Bang. 2025-11-01. Fairness-Aware Secure Communication in ISAC Systems with STAR-RIS and RSMA. https://arxiv.org/abs/2511.00721

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