This letter focuses on the problem of pilot assignment in cell-free massive MIMO systems. Exploiting the well-known Hungarian algorithms, two procedures are proposed, one maximizing the system throughput, and the other one maximizing the fairness across users. The algorithms operate based on the knowledge of large-scale fading coefficients as a proxy for the distances between users in the system, and take into account both the uplink and downlink performance. Numerical results show that the proposed pilot assignment algorithms are effective and outperform the many competing alternatives available in the literature.

中文翻译：

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基于匈牙利算法的无小区大规模MIMO导频分配


这封信重点讨论无小区大规模 MIMO 系统中的导频分配问题。利用著名的匈牙利算法，提出了两种程序，一种最大化系统吞吐量，另一种最大化用户之间的公平性。该算法基于大规模衰落系数的知识进行操作，作为系统中用户之间距离的代理，并考虑上行链路和下行链路性能。数值结果表明，所提出的导频分配算法是有效的，并且优于文献中的许多竞争替代方案。