In this letter, we consider a single-cell downlink non-orthogonal multiple access (NOMA) system using greedy scheduling with quality-based channel-state information (CSI) feedback (QCF), and propose the user selection and power allocation scheme to reduce the physical-layer latency and achieve target data rates while maximizing the sum rate at high signal-to-noise power ratio (SNR). Assuming Rayleigh fading channels, we investigate the transmission time interval index, which quantifies physical-layer latency, the overhead index of CSI feedback, and the average data rate of the proposed scheme. In addition, we show that the sum rates of NOMA and orthogonal multiple access systems using greedy scheduling with QCF are equal at high SNR.

中文翻译：

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在瑞利衰落信道中具有基于质量反馈的下行链路 NOMA 系统的用户选择和功率分配

在这封信中，我们考虑使用贪婪调度和基于质量的信道状态信息 (CSI) 反馈 (QCF) 的单小区下行链路非正交多址 (NOMA) 系统，并提出用户选择和功率分配方案以减少物理层延迟并实现目标数据速率，同时在高信噪比 (SNR) 下最大化总速率。假设瑞利衰落信道，我们研究了传输时间间隔指数，它量化了物理层延迟、CSI 反馈的开销指数以及所提出方案的平均数据速率。此外，我们表明 NOMA 和使用 QCF 贪婪调度的正交多址系统的总速率在高 SNR 时相等。