非理想双极化多天线系统中的信道信息反馈方法

在实际环境中,布置双极化天线时存在极化泄漏问题,影响信道信息量化反馈方法的精度,大规模天线系统中会造成预编码性能明显下降.本文从双极化信道模型出发,将信道矩阵分解为理想极化信道部分和极化泄露部分,并对各部分信道的特征矢量进行了分析,得到了各部分最佳特征矢量模型.基于这些模型,给出了基于多个分量加权合并的信道特征矢量量化反馈方法,能够有效地适应极化泄露带来的影响.仿真结果表明,该反馈方法能有效提高信道信息的量化效率和精度,进而获得明显的谱效率提升. 

CSI Feedback for Imperfect Multi-Polarized Massive MIMO System

The leakage between two polarization directions can be substantial if the number of transmit antennas (Tx) at eNodeB increases significantly. As a result, these codeword models may not be as efficient as in current MIMO system. In this paper, the characteristics of practical dual-polarized massive MIMO system with imperfect channel was investingated. To improve CSI accuracy, a multi-component feedback scheme was proposed, in which two CSI components target the perfect part and imperfect part of polarized channel respectively. A linear combination of the two components was assumed at both eNodeB and UE. Moreover, efficient feedback models were also formulated for the two parts. Finally, the performance of the proposed scheme is evaluated through extensive simulation.