Secure Efficiency Map-Enabled UAV Trajectory Planning

This letter investigates the dynamic changes of security and efficiency in an unmanned aerial vehicle (UAV)-to-ground network with a mobile UAV transmitter, a mobile ground receiver, and a fixed eavesdropper, respectively. To provide communication services with high security, spectrum efficiency, and energy efficiency, a concept of secure efficiency map (SEM) is devised and proposed to plan the UAV trajectory. Specifically, the security-efficiency index of each subarea in a certain area for a certain time slot is firstly calculated. Then, given that the security-efficiency index is time-varying, and CNN-LSTM network can effectively extract data features and accurately reflect time correlation, we take multiple SEMs drawn from the observed security-efficiency indices as the input of the CNN-LSTM network, and output future SEMs. Thirdly, based on predicted future SEMs, an SEM-enabled UAV trajectory planning scheme is further presented to jointly improve security and efficiency of the considered communication network. Finally, simulation results confirm the proposed SEM-enabled UAV trajectory planning scheme achieves a superior joint optimization of security, spectrum efficiency, and energy efficiency to other UAV trajectory planning schemes.