For large-scale antenna array multiple-input multiple-output (MIMO) systems, a typical solution often put forward for uplink detection consists in applying low-complexity linear receivers such as zero-forcing (ZF) and minimum mean-square error (MMSE) combiners. In this paper, the performance of uplink MMSE detection has been analyzed in the context of a multi-cell multiuser MIMO system. An approximate expression for the signal-to-interference-plus-noise ratio (SINR) is proposed, which is in simple form and becomes exact in the low SNR regime. This approximate SINR applies to systems where the base station (BS) has the statistical information of the out-of-cell interfering signals, and systems where the BS ignores the presence of such interfering signals. This approximate SINR is tight for arbitrary user powers, arbitrary number of antennas at the base station, and arbitrary channel correlation matrix associated with any particular user. Approximate expressions for capacity and bit-error rate/symbol-error rate have also been derived. Particularly, it can be proven that, when the MMSE receiver ignores the presence of out-of-cell interfering signals, the performance gap between ZF and MMSE vanishes in the high SNR regime.

中文翻译：

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多小区 MU-MIMO 系统中 MMSE 接收器的渐近性能分析


对于大规模天线阵列多输入多输出（MIMO）系统，通常为上行链路检测提出的典型解决方案包括应用低复杂度线性接收器，例如迫零（ZF）和最小均方误差（MMSE） ) 组合器。本文在多小区多用户 MIMO 系统的背景下分析了上行链路 MMSE 检测的性能。提出了信号与干扰加噪声比（SINR）的近似表达式，该表达式形式简单，并且在低 SNR 范围内变得精确。该近似SINR适用于基站(BS)具有小区外干扰信号的统计信息的系统，以及BS忽略此类干扰信号的存在的系统。该近似 SINR 对于任意用户功率、基站的任意数量的天线以及与任何特定用户相关的任意信道相关矩阵都是严格的。还导出了容量和误码率/误码率的近似表达式。特别地，可以证明，当MMSE接收器忽略小区外干扰信号的存在时，ZF和MMSE之间的性能差距在高SNR区域中消失。