天线方向性对MIMO系统信道容量影响

Effect of Antenna Directivity on the Channel Capacity of MIMO Systems

探讨三维空间散射环境中,Kronecker信道模型下天线方向性对空间衰落相关性和信噪比的影响,仿真研究均匀圆阵、线阵、矩形阵的多输入多输出系统信道容量.综合性给出天线方向性对信道容量的影响,即当定向天线主瓣对准来波时,定向天线方向性引起的信噪比增加超过了其相关系数对容量的负面影响,从而使信道容量整体优于全向天线.天线单元方向性越强,信道容量越大.

The effect of antenna directivity on both spatial fading correlation and signal-to-noise ratio based on Kronecker channel model is investigated in three dimensional scattering environments. The channel capacity of multiple-in multiple-out system for uniform circular array, line array, and rectangle array is studied. The contribution of antenna directivity to channel capacity is concluded that, when the main lobe of directive antenna points at the coming wave, the improved signal to noise ratio （SNR） resulting from the antenna directivity will exceed the negative impact caused by increased spatial fading correlation, leading to a better channel capacity than that of isotropic antenna. The stronger antenna directivity is, the greater the channel capacity.