On the Performance of Network-Assisted Full-Duplex Cell-Free Massive MIMO System with Multiple-Antenna Users

基于网络辅助全双工技术无蜂窝大规模多输入多输出(multiple input multiple output, MIMO)系统是目前无线通信领域的关键技术之一。然而，现有的研究都假设采用完美硬件配置的单天线用户设备发送和接收信号，这种架构限制了系统整体性能的进一步提升。鉴于此，本文针对网络辅助全双工无蜂窝大规模MIMO环境中的多天线用户通信展开研究。利用现有的加性量化噪声模型，推导了低精度模数转换器(analog-to-digital converters, ADCs)下上行和下行频谱效率(spectral efficiency, SE)的封闭表达式下界；基于不同规模的远端接入单元配置验证了理论结果的准确性；进一步利用MATLAB分别评估了用户天线数目以及ADC量化精度等参数对系统性能的影响。仿真结果表明，在网络辅助双工模式中引入多天线用户显著提升了系统的吞吐量和可达速率，这一性能增益与半双工结构具有一致性。Network-assisted full-duplex cell-free massive multiple-input multiple-output (MIMO) systems represent a pivotal technology in contemporary wireless communications. However, existing studies predominantly assume single-antenna user equipment with perfect hardware configurations for signal transmission and reception, which fundamentally constrains further enhancement of overall system performance. To bridge this research gap, this paper investigates multi-antenna user communications in network-assisted full-duplex cell-free massive MIMO environments. The existing additive quantization noise model is employed to derive closed-form lower bounds for spectral efficiency (SE) in both uplink and downlink transmissions under low-resolution analog-to-digital converters (ADCs). The theoretical derivations are validated through various remote access unit deployment configurations. Comprehensive MATLAB simulations are conducted to assess the impact of critical parameters, including user antenna count and ADC quantization precision, on system performance. Simulation results demonstrate that incorporating multi-antenna users in network-assisted duplexing mode yields significant improvements in system throughput and achievable rates, with performance gains exhibiting consistency with half-duplex architectures.