面对5G毫米波网络中多用户的高速率需求，为进一步加强毫米波网络中的下行链路非正交多址接入传输，提出一种基于角度和距离联合的新型用户配对方案。该方案充分考虑了天线阵列形成波束的高定向性和用户的随机性。基站根据用户之间的瞬时空间角度差和距离基站的位置信息来选择配对用户，并将适时地选择启用非正交多址接入方案。通过使用随机几何的方法，得出用户遍历总速率理论值。仿真结果表明，该方案得到的遍历总速率高于另外4种常见的用户配对方案，且存在距离阈值的最优值，该值使遍历总速率最大化。
For the features of high-speed and multiple-requirements of multiple users in 5G millimeter wave networks, in order to further enhance the downlink non-orthogonal multiple-access transmission in millimeter wave networks, a novel user pairing scheme based on angle and distance is proposed in this paper. This scheme fully considers the high directional beam-forming of the antenna array and the randomness of the user. The base station will choose to enable the nonorthogonal multiple access scheme based on the instantaneous spatial angle difference and the distance information between the paired users. Using methods from stochastic geometry, we derive the ergodic sum rate of the proposed scheme. Simulation results show that this scheme outperforms four other common user pairing schemes, and there is an optimal value of the distance threshold that maximizes the ergodic sum rate.
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