UAV Hovering Strategy Based on a Wirelessly Powered Communication Network.

With the development of wireless power transfer technology, wirelessly powered communication networks (WPCNs), which can provide a sustainable energy supply for the user equipment, have received extensive attention from researchers. An unmanned aerial vehicle (UAV)-based WPCN (U-WPCN) can effectively solve the problems of energy shortage and weak signal strength for ground terminals in remote areas. To establish a highly efficient U-WPCN, the service area for each UAV platform should be determined such that each UAV platform will hover at the optimal position according to the locations of the ground terminals in its group. Through hovering position optimization, this paper proposes two networking strategies for improving networking efficiency and maximizing communication performance. A greedy algorithm is used to find the optimal hovering point for each area; thus, the hovering points of all UAVs in the U-WPCN are finally obtained. Simulation results show that the UAV utilization efficiency can be significantly increased through the economical mode, and the terminal transmission rates can be improved for a given number of drones in the performance mode.