In this letter, an orbital angular momentum-based multiple-input multiple-output (OAM-MIMO) multiplexing system is integrated with non-orthogonal multiple access (NOMA) to enhance the user and sum channel capacities of the downlink NOMA for multiple users. The user and sum capacities of the proposed NOMA-OAM-MIMO scheme is analyzed and compared with other conventional schemes such as conventional NOMA with MIMO, and conventional orthogonal multiple access with OAM-MIMO multiplexing.

中文翻译：

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OAM-MIMO系统非正交多址信道容量分析

在这封信中，基于轨道角动量的多输入多输出 (OAM-MIMO) 多路复用系统与非正交多址 (NOMA) 相结合，以增强用户和下行链路 NOMA 的总信道容量，供多用户使用。对所提出的 NOMA-OAM-MIMO 方案的用户容量和总容量进行了分析，并与其他传统方案进行了比较，例如采用 MIMO 的常规 NOMA 和采用 OAM-MIMO 复用的常规正交多址接入。