Robust and Secure Resource Allocation for ISAC Systems: A Novel Optimization Framework for Variable-Length Snapshots

In this paper, we investigate the robust resource allocation design for secure communication in an integrated sensing and (ISAC) system. A multi-antenna dual-functional radar-communication (DFRC) base station (BS) serves multiple single-antenna legitimate users senses targets simultaneously, where already identified are treated as potential eavesdroppers. The DFRC BS scans a sector with sequence of dedicated beams, ISAC system takes snapshot environment during transmission each beam. Based on information, can acquire channel state information (CSI) Different from existing works that focused single snapshot, propose novel optimization framework jointly optimizes resources over snapshots adjustable durations. Besides, artificial noise (AN) is exploited by joint physical layer security provisioning. To end, optimize duration beamforming vector, covariance matrix AN maximization sum secrecy rate while guaranteeing minimum required average achievable maximum leakage constraint user. algorithm formulated non-convex problem, account imperfect CSI both make problem tractable, derive bound uncertainty region eavesdroppers’ small-scale fading based safe approximation, which facilitates development block coordinate descent-based iterative obtaining efficient suboptimal solution. Simulation results illustrate proposed scheme significantly enhance systems compared to three baseline schemes. Moreover, conventional multi-stage approach design, variable-length not only highly-directional offline beam but also allows us flexibly prioritize or depending application scenario.