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arXiv · 2502.11719

Synergizing Covert Transmission and mmWave ISAC for Secure IoT Systems

Abstract

This work focuses on the synergy of physical layer covert transmission and millimeter wave (mmWave) integrated sensing and communication (ISAC) to improve the performance, and enable secure internet of things (IoT) systems. Specifically, we employ a physical layer covert transmission as a prism, which can achieve simultaneously transmitting confidential signals to a covert communication user equipment (UE) in the presence of a warden and regular communication UEs. We design the transmit beamforming to guarantee information transmission security, communication quality-of-service (QoS) and sensing accuracy. By considering two different beamforming architectures, i.e., fully digital beamforming (FDBF) and hybrid beamforming (HBF), an optimal design method and a low-cost beamforming scheme are proposed to address the corresponding problems, respectively. Furthermore, building on the previously derived algorithm, two robust variants are proposed to address the more challenging case where the warden's CSI is imperfect. Numerical simulations validate the effectiveness and superiority of the proposed FDBF/HBF algorithms compared with traditional algorithms in terms of information transmission security, communication QoS and target detection performance.

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Lingyun Xu, Bowen Wang, Ziyang Cheng. 2025-02-17. Synergizing Covert Transmission and mmWave ISAC for Secure IoT Systems. https://doi.org/10.1109/jiot.2025.3585663

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