Document Type

Journal Article

Publication Title

IEEE Internet of Things Journal




School of Science




National Natural Science Foundation for Distinguished Young Scholar Key Program of Jiangsu Province Key project and topics

National Natural Science Foundation of China

Australian Research Council Natural Science Foundation on Frontier Leading Technology Basic Research Project of Jiangsu

Grant Number

ARC Number : DP210102169


This is an Authors Accepted Manuscript version of an article published by IEEE.

© 2021 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.

Lu, X., Yang, W., Yan, S., Li, Z., & Ng, D. W. K. (2022). Covertness and timeliness of data collection in UAV-aided wireless-powered IoT. IEEE Internet of Things Journal, 9(14), 12573-12587.


In this work, we aim to maximize the timeliness of data collection subject to a covertness constraint in unmanned aerial vehicle (UAV)-aided Internet-of-Things (IoT) networks, where a UAV periodically conducts wireless power transfer (WPT) to charge an energy-constrained IoT device and then the IoT device opportunistically sends its collected data to the UAV. To this end, we first derive a lower bound on the covertness constraint and an analytical expression for age of information (AoI) to characterize timeliness. Then, we jointly optimize the UAV’s transmit power for WPT, the WPT duration, and the data transmission duration by considering two practical scenarios. For the fixed total duration scenario, our analytical optimal solutions indicate that the total harvested energy at the IoT device is independent of the covertness constraint, although both the UAV’s transmit power and the WPT duration are significantly affected by the covertness constraint. With the optimized total duration scenario, we prove that the UAV’s optimal transmit power is always attained at its maximum value regardless of the existence of the covertness constraint, but the WPT and data transmission durations are sensitive to the required covertness. Overall, there exists a non-trivial tradeoff between the timeliness and covertness for data collection in the considered system, which is determined by the WPT design. Furthermore, our numerical results show that the optimal prior probability of the IoT device’s opportunistic transmission is generally not 0.5 for the fixed total duration, but it is indeed 0.5 for the optimized total duration.



Available for download on Saturday, December 23, 2023