UAV-assisted Uplink NOMA Networks: UAV Placement and Resource Block Allocation

Abstract

This paper studies an uplink network in which a hovering unmanned aerial vehicle (UAV) serves as a flying base station and multiple ground users access different resource blocks (RBs) with the aid of power-domain non-orthogonal multiple access (NOMA). We aim to maximize the sum of information rate of the network through appropriate UAV placement and RB allocation. The mixed integer nonconvex problem is decomposed into two layers. The inner layer, RB allocation given the position of the UAV, is solved by hill-climbing. The outer layer, UAV placement given the result of RB allocation of the inner layer, is solved by particle swarm optimization. Simulation results show that the proposed layered scheme outperforms existing resource allocation strategies.