This article mainly focus on addressing the non-orthogonal multiple access (NOMA) enhanced unmanned aerial vehicle (UAV)-to-Everything (U2X) networks. A novel three dimension (3D) network 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 network, we first derive the closed-form expressions for the outage probability and the ergodic rate of the paired NOMA Rxs. Both the diversity orders and the high-signal-to-noise (SNR) slopes of the paired NOMA Rxs are derived. The spectrum efficiency (SE) in both the NOMA and orthogonal multiple access (OMA) enhanced U2X networks are derived. Our analytical results demonstrate that the diversity order and the high-SNR slope of the proposed network are fading parameter $m$ and one, respectively. Numerical results are provided to confirm that: i) the proposed NOMA enhanced U2X networks have superior outage performance and SE compared with the OMA enhanced U2X networks; and ii) for the case of fixed LoS probability, the outage performance of the paired NOMA Rxs mainly depends on the poorer channel conditions.

中文翻译：

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依赖于 NOMA 的 UAV-to-Everything (U2X) 网络：随机几何模型

本文主要关注解决非正交多址（NOMA）增强型无人机（UAV）到万物（U2X）网络。通过利用随机几何工具，提出了一种新颖的三维 (3D) 网络，用于向球空间中随机漫游的 NOMA 接收器 (Rxs) 提供无线服务。为了评估所提出网络的性能，我们首先推导出配对 NOMA Rxs 的中断概率和遍历率的闭式表达式。导出成对的 NOMA Rx 的分集阶数和高信噪比 (SNR) 斜率。推导出 NOMA 和正交多址 (OMA) 增强型 U2X 网络中的频谱效率 (SE)。我们的分析结果表明，所提出的网络的分集阶数和高 SNR 斜率分别是衰减参数 $m$ 和 1。提供的数值结果证实：i) 与 OMA 增强型 U2X 网络相比，所提出的 NOMA 增强型 U2X 网络具有更好的中断性能和 SE；ii) 对于固定 LoS 概率的情况，配对的 NOMA Rxs 的中断性能主要取决于较差的信道条件。