In this letter, a precoded spatial modulation-aided cooperative nonorthogonal multiple access (NOMA), referred to as PC-NOMA, has been proposed for multiple-input and multiple-output (MIMO) downlink scenario. In PC-NOMA scheme, the base station (BS) broadcasts three users’ information over two time slots: in the first slot, the two near users receive data through direct links and in the second slot, the third user (far) receives data indirectly from the near users. The precoded direct links’ signal has been superposed with indirect link’s signal in broadcast phase at the BS. The indirect link’s signal has been decoded and forwarded at the direct link’s user using the successive-interference cancellation (SIC) method in cooperative phase. The symbol error rate (SER) and mutual information (MI) under inter-users interference (IUI) have been derived for the proposed PC-NOMA. The impact of various system parameters, such as the number of transmitting and receiving antennas, have been analyzed for the proposed PC-NOMA.

中文翻译：

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预编码空间调制辅助合作 NOMA

在这封信中，已针对多输入多输出 (MIMO) 下行链路场景提出了一种预编码的空间调制辅助协作非正交多址 (NOMA)，称为 PC-NOMA。在PC-NOMA方案中，基站（BS）在两个时隙上广播三个用户的信息：在第一个时隙，两个近端用户通过直接链路接收数据，在第二个时隙，第三个用户（远端）接收数据间接来自附近的用户。在BS广播阶段，预编码的直接链路信号与间接链路信号叠加。间接链路的信号已在直接链路的用户处使用协作阶段的连续干扰消除 (SIC) 方法进行解码和转发。已为提议的 PC-NOMA 推导出用户间干扰 (IUI) 下的符号错误率 (SER) 和互信息 (MI)。已针对提议的 PC-NOMA 分析了各种系统参数的影响，例如发射和接收天线的数量。