Joint downlink user power allocation and rate maximization in UAV relay assisted SWIPT-NOMA network

In this paper, in order to improve the performance of wireless fifth generation (5G) communication system and save power consumption, the research objectives of optimal power allocation and maximizing the total user rate in a multi-user cluster in the downlink of non-orthogonal multiple access (NOMA) access system are realized based on the simultaneous wireless information and power transfer (SWIPT). A SWIPT-NOMA system assisted by dynamic unmanned aerial vehicle (UAV) relay is constructed. The UAV relay dynamic programming under two-hop communication was firstly studied, and the global optimal power allocation strategy for downlink users of SWIPT-NOMA system is found. Finally, the optimal relay selection algorithm was used to maximize the total user rate, which was verified by Monto Carlo simulation. Simulation results show that compared with the traditional FDMA system scheme, the performance of the proposed system model in terms of outage probability, energy consumption and total user rate of multi-user cluster deployed in dynamic UAV relay system under different distribution scenarios is better than that of the benchmark scheme.