LAUSR

This letter investigates a two-way mobile relaying strategy where a relay mounted on a unmanned aerial vehicle (UAV) helps bidirectional communication of a pair of ground nodes (GNs). In order to deal with the minimum average rate maximization problem between two GNs, UAV trajectory, transmit power, and bandwidth are jointly optimized by fully utilizing the mobility of UAV and communication resources. To solve this problem, we apply a successive convex approximation technique for non-convex constraints by introducing new surrogate functions. Since all variables are jointly updated at the same iteration, we can yield a Karush-Kuhn-Tucker (KKT) point at the convergence point from the proposed algorithm. The effectiveness of the proposed algorithm is demonstrated in numerical results.