In this paper, we discuss a non-orthogonal multiple access (NOMA) scheme to exploit a high diversity gain using repetition, namely repetition-based NOMA. Unlike conventional power-domain NOMA, all the users can have the same transmit power, but different number of repetitions. Thanks to a high diversity gain, a low outage probability can be achieved without instantaneous channel state information (CSI) feedback for power allocation. A closed-form expression for an upper-bound on the outage probability is derived so that the values of key parameters can be decided to maintain the outage probability below a target value. We also consider the average error probability for finite-length codes. Simulation results are compared with the derived bounds and it is shown that the bounds are reasonably tight and can be used to decide key parameters (e.g., code rates) to guarantee target error probabilities.

中文翻译：

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基于重复的 NOMA 传输及其中断概率分析

在本文中，我们讨论了一种非正交多址 (NOMA) 方案，以利用重复利用高分集增益，即基于重复的 NOMA。与传统的功率域 NOMA 不同，所有用户可以具有相同的发射功率，但重复次数不同。由于高分集增益，无需用于功率分配的瞬时信道状态信息 (CSI) 反馈即可实现低中断概率。推导出中断概率上限的封闭形式表达式，以便可以决定关键参数的值，以将中断概率保持在目标值以下。我们还考虑了有限长度代码的平均错误概率。将仿真结果与导出的界限进行比较，结果表明界限相当紧，可用于确定关键参数（例如，