Energy Minimization for Data Collection in Wireless Sensor Networks with UAV

Unmanned aerial vehicle (UAV) enabled communication has emerged as an appealing technology in wireless sensor networks (WSNs) for efficient data collection. This paper studies the energy issues for data collection in UAV enabled WSNs. It is revealed that a fundamental tradeoff exists between the energy consumption of UAV and that of all sensor nodes (SNs). To characterize such a tradeoff, an optimization problem is formulated to minimize the weighted sum of the energy consumption of UAV and SNs, via jointly optimizing the UAV trajectory, mission completion time, as well as the wake-up scheduling for all SNs. As the formulated problem is a non-convex problem with infinite variables over time, it is difficult to be optimally solved. To tackle this issue, the original problem is transformed into a discretized equivalent with path discretization method, and then a locally optimal solution is obtained by applying the successive convex approximation and block coordinate descent techniques. Simulations are conducted to corroborate our study and show the flexible tradeoff achieved by the proposed design for energy balance between UAV and SNs.