3D Location Optimization for UAV-Aided Uplink/Downlink Transmissions

Abstract

In this paper, we investigate the placement of an unmanned aerial vehicle (UAV) base station (BS) which serves multiple ground users (GUs). By taking into account both the uplink and downlink transmissions, we aim to optimize the 3D location of the UAV for maximizing the minimum average sum rate. The 3D location optimization problem is divided into the horizontal coordinate and the height optimization subproblems, respectively. We further apply the CVX toolbox to solve the horizontal coordinate optimization problem and transform the height optimization problem into the elevation angle optimization problem to obtain its solution. Our numerical results show that the minimum average sum rate of the proposed 3D location optimization scheme is higher than that of the numerical search (NS) based location optimization method, that of the energy-efficient maximal coverage (EEMC) based location optimization method and that of the random location method, for different distributions of GUs’ locations.