In the existing non-orthogonal multiple access (NOMA) works, ordering users depending on their distances is widely used, which can provide tractable results. However, it is not accurate in dense networks with considering the line-of-sight (LoS)/non-line-of-sight (NLoS) propagation and multipath fading. Hence, the received instantaneous signal power (ISP)-based ordering is investigated in this letter. We derive the probability of the near user in distance-based ordering being the strong user in ISP-based ordering, which is termed as the accuracy probability, and also analyze the respective coverage probabilities. The analytical and simulation results show that the accuracy probability varies with base station (BS) density and the gap between the distance and ISP-based ordering highly depends on the BS density and power allocation coefficient.

中文翻译：

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具有基于 ISP 的用户订购的下行链路 NOMA 密集网络的覆盖分析

在现有的非正交多址（NOMA）工作中，广泛使用根据用户的距离对用户进行排序，可以提供易于处理的结果。然而，考虑到视距 (LoS)/非视距 (NLoS) 传播和多径衰落，它在密集网络中并不准确。因此，在这封信中研究了基于接收瞬时信号功率 (ISP) 的排序。我们推导出基于距离的排序中的近用户是基于ISP的排序中的强用户的概率，称为准确概率，并分析各自的覆盖概率。分析和仿真结果表明，准确概率随基站（BS）密度而变化，距离与基于ISP的排序之间的差距高度依赖于基站密度和功率分配系数。