Joint Optimization of Flight Path and Power Allocation in A UAV Relay-assisted Communication System

Since the transmit power of the unmanned aerial vehicle (UAV) is limited, it exerts remarkable influence on the throughput of communication system. In view of this situation, this paper studies the two-hop UAV relay system, in which the UAV serves as a relay to decode and forward the information from source to destination. To maximize system throughput in the limited flight time, we jointly implement path optimization and power allocation of source/relay transmitters. For the optimization problem involved here is non-convex, we propose an efficient iterative algorithm, jointly considering the block coordinate descent method, the successive convex approximation technology, and the idea of introducing slack variables. The simulation results verify that this scheme significantly improves the system throughput compared with other two schemes where either power or path gets optimized only.