Opportunistic Adaptive Non-Orthogonal Multiple Access in Multiuser Wireless Systems: Probabilistic User Scheduling and Performance Analysis
Opportunistic Adaptive Non-Orthogonal Multiple Access in Multiuser Wireless Systems: Probabilistic User Scheduling and Performance Analysis
复制标题
多用户无线系统中的机会自适应非正交多址接入：概率用户调度和性能分析
DOI：
10.1109/twc.2020.2999814
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发表时间：
2020-09-01
影响因子：
10.4
通讯作者：
Xue, Xuan
中科院分区：
文献类型：
--
作者：
Yang, Long;Jiang, Hai;Xue, Xuan
本文设计了一种新颖的机会自适应非正交多址（OA-NOMA）策略，其中基站（BS）采用 NOMA 来服务从 M 个 NU 和 K 个 FU 机会调度的近用户（NU）-远用户（FU）对。具体地，到调度的NU-FU对的NOMA传输自适应地以两种模式之一操作： 直接NOMA模式，其中BS使用NOMA直接服务于调度的NU-FU对；以及协作NOMA模式，其中被调度的NU从BS接收两个被调度用户想要的消息，然后转发被调度的FU想要的消息。针对OA-NOMA策略，提出了调度候选获取方法和概率用户对调度方案，分别保证传输可靠性和提高调度公平性。为了评估调度公平性，我们制定了最大-最小公平性准则，并表明 OA-NOMA 策略大致实现了最大-最小公平性。 OA-NOMA策略的可靠性还根据中断概率和分集顺序进行评估。对于停电概率，我们推导了一个近似表达式，并通过数值验证了其严密性。对于多样性阶数，我们表明所提出的 OA-NOMA 策略实现了 M 的多样性阶数。
This paper designs a novel opportunistic adaptive non-orthogonal multiple access (OA-NOMA) strategy, where a base station (BS) employs NOMA to serve a near user (NU)-far user (FU) pair opportunistically scheduled from M NUs and K FUs. In particular, the NOMA transmission to the scheduled NU-FU pair adaptively operates in one of two modes: Direct NOMA mode, in which the BS directly serves the scheduled NU-FU pair with using NOMA; Cooperative NOMA mode, in which the scheduled NU receives the messages intended by both scheduled users from the BS, and then forwards the message intended by the scheduled FU. For the OA-NOMA strategy, a scheduling candidate acquisition method and a probabilistic user pair scheduling scheme are proposed to guarantee the transmission reliability and improve the scheduling fairness, respectively. To evaluate the scheduling fairness, we develop a max-min fairness criterion and show that the OA-NOMA strategy approximately achieves max-min fairness. The reliability of the OA-NOMA strategy is also evaluated in terms of outage probability and diversity order. For the outage probability, we derive an approximate expression and numerically verify its tightness. For the diversity order, we show that the proposed OA-NOMA strategy achieves a diversity order of M.