MIMO信道中空域相关特性分析

利用二维多输入多输出(multiple input multiple output,MIMO)信道模型进行相关性分析,会丢失一维空域信息。为此,建立无视距信号环境下的三维MIMO信道模型,利用VMF(von mises fisher)函数模拟来波信号方位角与俯仰角功率谱分布,并详细推导了考虑与不考虑互耦作用时的空域相关函数的解析表达式。最后,在考虑天线互耦情况下,运用仿真实验分析接收端的信号空域相关性与天线间距、平均达波角及达波角角度扩展之间的关系。实验结果表明,在建筑密集环境下,来波俯仰角扩展和互耦是影响信号间的相关系数的重要因素。

Analysis of spatial correlation of a channel model for MIMO

Some spatial information of signal will be lost when we analyse the spatial correlation of signal using 2-dimensional channel model for multiple input multiple output (MIMO). So a 3-dimensional channel model for MIMO is built in the non-line-of-sight signal circumstance. The von mises fisher (VMF) function is used to describe their power distribution of angle of arrival (AOA) within the propagation environment in azimuth and co-elevation, the spatial correlation of the MIMO channel with and without the impact of coupling is derived in detail in this paper. Finally, considering mutual coupling effect on the antennas, we analyse the relation between the spatial correlation and the space of antennas and AOA and angle spread of AOA''. From the results of experiment, we find the angle spread of AOA and mutual coupling between antennas are important factors which affect the correlation of signal in the dense building circumstance.