Secure Communication in UAV-Enabled Mobile Relay Systems

Abstract

This paper considers an unmanned aerial vehicle (UAV) as a buffer-aided mobile relay systems. A UAV is exploited to forward confidential information between a ground source and legitimate ground destinations in a time division multiple access (TDMA) mode in the presence of a potential eavesdropper. Considering the fairness among users, the optimization problem of minimum secrecy rate maximization among users is formulated by jointly optimizing UAV’s trajectory, power control and user scheduling. To circumvent the non-convex optimization problem, an efficient alternating iterative algorithm is proposed to obtain a suboptimal solution by introducing slack variables and applying successive convex approximate (SCA). Simulation results illustrate that the proposed algorithm outperforms the benchmark schemes in terms of minimum secrecy rate.