论文标题
团队最佳的MMSE组合用于无细胞的大型MIMO系统
Team-Optimal MMSE Combining for Cell-Free Massive MIMO Systems
论文作者
论文摘要
预计无细胞（CF）大量多输入多输出（MIMO）系统将实施高级合作通信技术，以使地理分布式访问点共同为用户设备提供服务。在\ emph {团队理论}的基础上，我们在有限的数据和灵活的频道状态信息（CSI）共享下设计上行链路团队最小于点错误（TMMSE）。考虑到通道估计误差和试点污染的效果，提出了最低的MSE问题，以得出单向TMMSE，集中式TMMSE和统计TMMSE组合函数，其中CF大量MIMO系统在单向CSI中运行，分别为CSI，中心室CSI和统计CSI CSI和统计CSI共享。然后，我们得出所考虑系统的上行链路光谱效率（SE）。结果表明，与集中式TMMSE相比，单向TMMSE仅需要CSI分担负担的一半，而SE绩效损失则只需要。此外，可以通过增加每个AP的AP和天线数量来有效地减少单向和集中式TMMSE组合方案之间的性能差距。
Cell-free (CF) massive multiple-input multiple-output (MIMO) systems are expected to implement advanced cooperative communication techniques to let geographically distributed access points jointly serve user equipments. Building on the \emph{Team Theory}, we design the uplink team minimum mean-squared error (TMMSE) combining under limited data and flexible channel state information (CSI) sharing. Taking into account the effect of both channel estimation errors and pilot contamination, a minimum MSE problem is formulated to derive unidirectional TMMSE, centralized TMMSE and statistical TMMSE combining functions, where CF massive MIMO systems operate in unidirectional CSI, centralized CSI and statistical CSI sharing schemes, respectively. We then derive the uplink spectral efficiency (SE) of the considered system. The results show that, compared to centralized TMMSE, the unidirectional TMMSE only needs nearly half the cost of CSI sharing burden with neglectable SE performance loss. Moreover, the performance gap between unidirectional and centralized TMMSE combining schemes can be effectively reduced by increasing the number of APs and antennas per AP.
