The Concept of Time Sharing NOMA into UAV-Enabled Communications: An Energy-Efficient Approach

This paper proposes a framework for the optimal power allocation during time sharing non-orthogonal multiple access (TS-NOMA) transmissions performed by an unmanned aerial vehicle (UAV) in the context of large-scale scenario. The objective of this proposed framework is to maximize the energy efficiency (EE) within the UAV communication range. The idea behind is to propose a communication system that merges the advantages of UAV communications with the ones offered by the TS-NOMA paradigm maximizing the downlink EE among users. The resulting model finds applicability in performing energy efficient transmissions into power-constrained communication scenarios such as in disaster communications. Performance investigations regarding the proposed framework show its capability in finding the optimal energy efficient configuration of power resources, respecting both the power constraints at the transmitter and the quality-of-service requirement of the users. Furthermore, the proposed framework resulted able to maintain a good level of throughput fairness among users in downlink.