论文标题
迭代加权的MMSE上行链路预编码，用于无细胞的大型MIMO
Iteratively Weighted MMSE Uplink Precoding for Cell-Free Massive MIMO
论文作者
论文摘要
在本文中，我们研究了一个无细胞的大型MIMO系统，其访问点和用户设备在Weichselberger Rayleigh褪色通道上配备了多个天线。我们基于具有最大比率（MR）的两层解码结构的上行频谱效率（SE）或分别在第二层实施的最佳大型褪色解码方法的两层解码结构（MR）或局部最小均时误差（MMSE）。为了最大化加权总和SE，提出了仅建议仅使用通道统计信息的迭代加权sum-MMSE（I-WMMSE）算法的上行链路预编码结构。此外，随着MR组合在第一层中应用，我们在封闭形式中得出了新颖的可实现的SE表达式和最佳的预编码结构。数值结果验证了我们提出的结果，并表明I-WMMSE预编码可以实现出色的总和SE性能。
In this paper, we investigate a cell-free massive MIMO system with both access points and user equipments equipped with multiple antennas over the Weichselberger Rayleigh fading channel. We study the uplink spectral efficiency (SE) based on a two-layer decoding structure with maximum ratio (MR) or local minimum mean-square error (MMSE) combining applied in the first layer and optimal large-scale fading decoding method implemented in the second layer, respectively. To maximize the weighted sum SE, an uplink precoding structure based on an Iteratively Weighted sum-MMSE (I-WMMSE) algorithm using only channel statistics is proposed. Furthermore, with MR combining applied in the first layer, we derive novel achievable SE expressions and optimal precoding structures in closed-form. Numerical results validate our proposed results and show that the I-WMMSE precoding can achieve excellent sum SE performance.
