单载波大规模MIMO频域预均衡与波束成型的联合设计

本文考虑了单载波频域预处理技术作为多用户大规模MIMO下行链路通信的传输方案。首先,根据系统模型推导出宽带多用户大规模MIMO下行链路预编码的形式,其中包括匹配滤波(MF)和迫零(ZF)预编码方案。随后,通过理论推导和仿真验证得到两种预编码方案下OFDM与SC-FDP的用户和速率表达式,结果显示SC-FDP在大规模MIMO场景下拥有与OFDM相似的用户和速率。然后,通过仿真实验对比OFDM与SC-FDP的峰均比(PAPR),结果表明在用户数目较少的情况下,SC-FDP相对于OFDM具有更小的PAPR,随着用户数增加,两者之间差异逐渐减小。最后,对多用户MIMO下行链路中OFDM与SC-FDP的运算复杂度进行比较,二者系统复杂度相当,而SC-FDP主要运算任务在基站端完成。基于以上比较分析,SC-FDP在宽带多用户大规模MIMO下行链路中是一种很有潜力的传输方案。 

Joint Design of Frequency Domain Pre-equalization and Beamforming for Single Carrier Massive MIMO System

In this paper, we investigate the performance of single-carrier frequency domain processing as the downlink transmission scheme in a broadband multi-user and massive multiple input multiple output system. Firstly, the pre-coding forms in multi-user massive MIMO downlink are derived, and both matched filtering (MF) and zero forcing (ZF) precoding schemes are included. Then, the theoretical derivations and simulations of sum-rate in both OFDM and SC-FDP systems are given and show that SC-FDP has similar performance in sum-rate compared with OFDM in large-scale MIMO system. After that, the peak-to-average ratio (PAPR) between OFDM and SC-FDP are analyzed, and show that SC-FDP has a smaller PAPR than OFDM when the number of users is small, and as the number of users increasing the gap decreases. Finally, we analyze the computational complexity of OFDM and SC-FDP, the overall computational complexity of the two system is comparable except that the main computational task of SC-FDP is completed at the base station. Due to the mentioned facts, SC-FDP can be considered as a very promising transmission scheme in multi-user massive MIMO downlink.