采用迫零接收机的大规模MIMO上行链路支持用户数研究

Uplink supportive number of users in massive MIMO systems with ZF receivers

文中主要研究了采用迫零接收机的大规模MIMO系统上行链路所支持的用户数。通过严格的数学推导,给出了适用于任何基站天线数的用户可达上行速率下界,并依据此理论计算结果,分别在用户无最低速率限制和用户有最低速率限制条件下,对小区所支持的用户数进行了研究,给出了可令小区总速率最大的用户数表达式,并同时提出了得到此最大速率的用户调度算法。仿真结果显示不论用户有无最低速率限制条件,小区总速率最大时所支持的用户数都是随着基站天线数的增加而呈近似线性增长的,这进一步表明了大规模MIMO对提高小区系统性能和提升服务用户数方面有显著的作用。

The supportive number of users in uplink massive MIMO systems with ZF receivers is studied.By strict derivation,the lower bound of the achievable rate of each user is obtained for any finite number of base station antennas. Based on this theoretical result,the supportive number of users with and without the minimum achievable rate constraints is researched,respectively. Through analyzing the optimal problem of maximizing the overall sum rate,the expression of optimal number of users is given and the user scheduling algorithm for achieving the maximized sum rate is presented. Simulation results show that the supportive number of users increases linearly with the number of base station antennas,thus it means that the massive MIMO systems can improve the number of users and that the cell can serve simultaneously.