Joint Resource Allocation and Position Optimization in NOMA-based Multi-UAV Wireless Communication Networks

In this paper, we study an uplink multi-unmanned aerial vehicle (UAV) wireless communication network where multi-UAV are deployed to serve the ground users by utilizing the non-orthogonal multiple access (NOMA) technology. The goal is to minimize the total transmit power of users by jointly optimizing the user association, sub-channel assignment, power allocation and UAVs’ position. The formulated problem is a mixed integer non-convex optimization that is difficult to solve in optimal approach. By applying the convex optimization tools, successive convex approximation (SCA) and Lagrange dual approaches, we solve the optimization problem then we propose an efficient iterative algorithm. Numerical results confirm that the proposed scheme can provide a better performance compared to the orthogonal multiple access (OMA), random position of UAVs in NOMA (RP-NOMA) and OMA (RP-OMA) schemes in both of the transmit power and sum-rate performance metrics.