Secure Beamforming for ISAC Systems Under Communication Eavesdropper and Sensing Eavesdropper

TL;DR

This paper proposes a secure beamforming method for ISAC systems that maximizes secrecy rate against both communication and sensing eavesdroppers, using advanced optimization techniques.

Contribution

It introduces a joint secure beamforming algorithm for ISAC systems considering dual eavesdroppers, validated by theoretical analysis and simulations.

Findings

The proposed beamforming scheme effectively enhances security in ISAC systems.

SDR does not cause sub-optimality in the formulated problem.

Simulation results demonstrate the scheme's superiority over existing methods.

Abstract

Due to great efficiency improvement in resource and hardware space, integrated sensing and communication (ISAC) has gained much attention. In the paper, the physical layer security (PLS) of ISAC system under communication eavesdropper together with sensing eavesdropper is investigated. The system secrecy rate is maximized by transmit beamforming design of communication and sensing signals when taking sensing security, sensing performance and transmit power constraint into consideration. To deal with the formulated non-convex optimization problem, the successive convex approximation (SCA) together with the first-order Taylor expansion and semidefinite relaxation (SDR) is utilized. Additionally, it is theoretically validated that the SDR does not yield sub-optimality in the paper. Thereafter, an iterated joint secure beamforming algorithm against communication and sensing eavesdroppers is proposed. Simulation results validate the effectiveness and advance of the proposed scheme.