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UAV-Assisted Data Collection for Dynamic and Heterogeneous Wireless Sensor Networks

To consider the heterogeneity of sensor nodes (SNs) and further protect the SNs with low residual energy, in this letter, we propose an energy-saving UAV-assisted data collection framework for a heterogeneous wireless sensor network (WSN), where the working mode of each SN is dynamically determined by its residual energy and a certain energy threshold. Our aim is to minimize the WSN’s energy consumption by jointly optimizing the energy threshold, SNs’ working modes and cluster head (CH) selection, while ensuring successful data transmission and satisfying UAV trajectory length constraint. To address it, we propose a one-dimensional search method to find the optimal energy threshold, and leverage a sequential rank-one constraint relaxation algorithm to select the CHs. Numerical results justify that the performance of our proposed approach is more energy-saving than the existing benchmarks.