MIMO OTA测试区域扩大方法及信道建模实现原理

Test Zone Extension Method and Channel Modeling Principle in MIMO OTA

本文介绍了当前MIMO OTA测试方法的几个类别,着重对基于暗室和多探头的测试方法及其原理进行了阐述,在信道建模的理论基础上提出了将空间相关性函数作为评价因子,对信道仿真器的物理通道和配置进行优化的方法。通过仿真分析了在同等物理通道数量的情况下,优化算法能够得到更大的测试区域,进而将此结论用于全环多探头方案,第一次颠覆了业界原先认为全环法最少需要8个双极化探头,即16个物理通道的信道仿真器才能进行准确测试的看法。在广播电视规划院全环法多探头暗室中,进行了信道空间相关性验证测试,以及4款不同手持终端的吞吐量测试,实测数据验证了算法的有效性:在目前3GPP和CTIA定义的UMi信道模型中,仅占用信道仿真器的8个物理通道就可以实现常规16个物理通道才能完成的双极化全环法MIMO OTA测试,且两者的吞吐量曲线相互重合。

MPAC(Multi-Probe Anechoic Chamber)-based testing methods for MIMO capable equipments are attractive due to its ability to reconstruct spatial-temporal characteristic in controllable way. Conventional MPAC is costly because 16 physical channels are a minimum requirement for full-ring setup. The test zone is limited to 0.7 lambda in MPAC with 16 channels for 8 dual polarization probes coni guration. This paper has developed an optimization algorithm for extension size of test zone or cut down required number of physical channels. The simulations are showed for analysis and measurement results are given, which means the ef ectiveness of the algorithm is achieved. Furthermore, the practice of MPAC in Academy of Broadcasting Planning(ABP) shows that the size of anechoic chamber for MIMO OTA can be small.