In this paper, we consider a prospective receiving hybrid beamforming structure consisting of several radio frequency (RF) chains and abundant antenna elements in multi-input multi-output (MIMO) systems. Due to conventional costly full connections, we design an enhanced partially-connected beamformer employing low-density parity-check (LDPC) based structure. As a benefit of LDPC-based structure, information can be exchanged among clustered RF/antenna groups, which results in a low computational complexity order. Advanced message passing (MP) capable of inferring and transferring information among different paths is designed to support LDPC-based hybrid beamformer. We propose a message passing enhanced antenna and RF chain selection (MARS) scheme to minimize the operational power of antennas and RF chains of the receiver. Furthermore, sequential and parallel MP for MARS are respectively designed as MARS-S and MARS-P schemes to address convergence speed issue. Simulations have validated the convergence of both the MARS-P and the MARS-S algorithms. Owing to asynchronous information transfer of MARS-P, it reveals that higher power is required than that of MARS-S, which strikes a compelling balance between power consumption, convergence, and computational complexity. It is also demonstrated that the proposed MARS scheme outperforms the existing benchmarks using heuristic method of fully-/partially-connected architectures in open literature in terms of the lowest power and highest energy efficiency.

翻译：本文针对多输入多输出（MIMO）系统中由多个射频（RF）链和大量天线单元构成的接收端混合波束成形结构展开研究。为替代传统高成本的全连接架构，我们设计了一种基于低密度奇偶校验码（LDPC）结构的增强型部分连接波束成形器。得益于LDPC结构，信息可在聚类后的射频/天线组之间进行交换，从而显著降低计算复杂度。我们进一步设计了能够在不同路径间推理和传递信息的先进消息传递（MP）机制，以支持基于LDPC的混合波束成形器。在此基础上，提出了一种基于消息传递增强的天线与射频链选择（MARS）方案，旨在最小化接收端天线和射频链的工作功耗。针对收敛速度问题，分别设计了MARS的串行与并行消息传递机制（MARS-S与MARS-P方案）。仿真结果验证了MARS-P与MARS-S两种算法的收敛性。由于MARS-P采用异步信息传递机制，其所需功耗高于MARS-S方案，从而在功耗、收敛性与计算复杂度之间实现了引人关注的权衡。进一步证明，与现有文献中采用全连接/部分连接架构的启发式基准方法相比，所提MARS方案在最低功耗与最高能效方面均具有显著优势。