In this letter, we investigate the secrecy outage performance of a cooperative non-orthogonal multiple access (NOMA) network, where a base station (BS) communicates with multiple cell-centre users and a cell-edge user in the presence of an eavesdropper. It is assumed that there is no direct link between the BS and the cell-edge user, and thus one of the cell-centre users is selected to act as a relay for the cell-edge user. Particularly, the selected cell-centre user adopts the simultaneous wireless information and power transfer (SWIPT) for decoding information and harvesting energy for forwarding. The closed-form approximate expression for the system secrecy outage probability is derived under the max-min user selection (MMUS) strategy. The theoretical results are verified by simulations, and it is shown that the MMUS strategy outperforms various benchmark strategies.

中文翻译：

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与 SWIPT 合作的 NOMA 网络的保密中断性能分析


在这封信中，我们研究了协作非正交多址（NOMA）网络的保密中断性能，其中基站（BS）在窃听者存在的情况下与多个小区中心用户和小区边缘用户进行通信。假设基站与小区边缘用户之间没有直接链路，则选择其中一个小区中心用户作为小区边缘用户的中继。具体地，所选择的小区中心用户采用同时无线信息和功率传输（SWIPT）来解码信息并收集能量以进行转发。在最大-最小用户选择（MMUS）策略下导出了系统保密中断概率的封闭式近似表达式。通过仿真验证了理论结果，表明MMUS策略优于各种基准策略。