Age of Information Oriented Data Collection via Energy-Constrained UAVs in Wireless Sensor Networks

In this paper, an age of information (AoI) oriented data collection scheme is proposed for wireless sensor networks with energy-constrained unmanned aerial vehicles (UAVs). Different from traditional approaches that focus on one single UAV, we advocate the activation of multiple candidate UAVs to improve the AoI performances. However, coordinating multiple UAVs complicates the data collection strategies of each UAV, rendering AoI minimization a formidable challenge. To address the intractable formulated optimization problem, we propose a heuristic two-step algorithm based on greedy search for multiple UAVs. Specifically, we address the coordination of multiple UAVs through a novel algorithm grounded in graph theory and kernel K-means methods. Concurrently, we devise an energy-constrained trajectory planning algorithm to optimize data collection for each activated UAV. The numerical results validate the accuracy of the proposed algorithm, and demonstrate that both average AoI and energy consumption per UAV can be reduced when more energy-constrained UAVs are involved in the data collection process for wireless sensor networks.