Title: Hybrid centralized-distributed precoding in fronthaul-constrained CF-mMIMO systems Show Chinese title

Title: 前传受限的CF-mMIMO系统中的混合集中式-分布式预编码

Abstract: We investigate a fronthaul-limited cell-free massive multiple-input multiple-output (CF-mMIMO) system and propose a hybrid centralized-distributed precoding strategy that dynamically adapts to varying fronthaul and spectral efficiency (SE) requirements. The proposed approach divides users into two groups: one served by centralized precoding and the other by distributed precoding. We formulate a novel optimization problem for user grouping and power control aimed at maximizing the sum SE, subject to fronthaul and per-access point (AP) power constraints. To tackle the problem, we transform it into a tractable form and propose efficient solution algorithms. Numerical results confirm the hybrid scheme's versatility and superior performance, consistently outperforming fully centralized and distributed approaches across diverse system configurations. Show Chinese abstract

Abstract: 我们研究了一个前传受限的无蜂窝大规模多输入多输出（CF-mMIMO）系统，并提出了一种混合集中式-分布式预编码策略，该策略可动态适应不同的前传和频谱效率（SE）需求。 所提出的方法将用户分为两组：一组由集中式预编码服务，另一组由分布式预编码服务。 我们提出了一个新颖的优化问题，用于用户分组和功率控制，旨在最大化总SE，同时满足前传和每个接入点（AP）的功率约束。 为了解决这个问题，我们将问题转化为一种易于处理的形式，并提出了高效的解决方案算法。 数值结果证实了混合方案的通用性和优越性能，在各种系统配置下始终优于完全集中式和分布式方法。