UAV trajectory design based on retransmission

Abstract

Unmanned Aerial Vehicles (UAVs) have been widely used for data collection due to their high flexibility and ability to provide line-of-sight links. In existing studies, it is generally assumed that ground users can transmit only once, while in real systems, ground-based IoT devices can enhance the communication range by transmitting the same data multiple times. Therefore, this paper considers the UAV data collection problem in two different retransmission modes and models it as maximizing the number of users that can be served by the system for a determined amount of UAV onboard energy. Since the problem is a mixed integer nonlinear problem, it is difficult to solve directly. Therefore, it is decomposed into three subproblems by alternating optimization and solved by successive convex approximation (SCA). The simulation results show that the number of users that can be served by the system can be effectively increased by considering the retransmission of ground users.