Power Control for UAV-Aided Multiuser Covert IoT Communications Against Colluding Wardens

Wu Wang

School of Mathematics and Computer Science, Yunnan Minzu University, Kunming, Yunnan 650504, China

*Corresponding author

Unmanned aerial vehicles (UAVs) can rapidly provide wireless access for Internet of Things (IoT) users in emergency, remote, and temporary service scenarios, whereas their line-of-sight air-ground links make signal transmission susceptible to detection. This paper explores a multi-user UAV-aided covert IoT communication system, in which ground wardens improve their detection performance through collusion. The UAV serves legitimate users sequentially along a predefined trajectory. A portion of wardens shares detection observations and forms a super-warden via equal-gain combining. Under noise uncertainty, this paper derives the optimal detection thresholds and the minimum total detection error probability expressions for independent wardens and super wardens. Subsequently, an average covert transmission rate maximization problem is formulated under covertness constraints, peak power constraints, and average power budgets. Through equivalent transformation of covertness constraints, the original problem is converted into a convex optimization problem and solved using the CVX tool. Finally, numerical results verify the theoretical analysis and illustrate the influences of collusion strength, flight altitude, transmit power and other factors on the system’s covert performance.

Covert communication, UAV-aided IoT, colluding wardens, energy detection, noise uncertainty, power control

Yumei Yang, Honghui Cha, Fei Lin, Ruquan Wang, and Wu Wang (2026). Power Control for UAV-Aided Multiuser Covert IoT Communications Against Colluding Wardens. Journal of Networking and Network Applications, Volume 6, Issue 3, pp. 167–177. https://doi.org/10.33969/J-NaNA.2026.060305.

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