Non-Orthogonal Multiple Access in Air-to-Everything (A2X) Networks

This paper investigates the non-orthogonal multiple access (NOMA) enhanced Air-to-Everything (A2X) frameworks. A novel 3-Dimension unmanned aerial vehicles (UAVs) framework for providing wireless services to randomly roaming NOMA receivers (Rxs) in the sphere space is proposed by utilizing stochastic geometry tools. In an effort to evaluate the performance of the proposed framework, we first derive closed-form expressions for the outage probability of paired NOMA Rxs. For obtaining more insights, we investigate the diversity order of NOMA enhanced A2X frameworks. Our analytical results demonstrate that the diversity order and the high SNR slope of the proposed framework are m. Numerical results are provided to confirm that for the case of fixed LoS probability, the outage performance of paired NOMA Rxs mainly depends on users with poor channel conditions.