三维传播环境天线阵列空域相关性研究

Spatial correlation for antenna array under arbitrary 3D propagation scenarios

针对任意三维传播环境下多天线空域相关性求解复杂的问题,提出一种基于角度域脉冲采样的高效近似计算方法。针对均匀角度谱分布,详细推导出了天线空域相关系数的闭合表达式和近似表达式;针对非均匀任意角度谱,利用有限个均匀二维采样脉冲加权叠加进行逼近,从而将天线空域相关系数等效为多个均匀采样脉冲对应相关系数的加权之和。基于实测的Von Mises Fisher角度谱,仿真结果表明,当采样间隔小于2°时,所提方法运算量仅为数值积分方法的十分之一,而绝对误差小于0.005,可以应用于多天线分集、多输入多输出系统性能评估及天线阵列流型优化等场合。

Since analyzing spatial correlation between multiple antennas under 3Dpropagation scenarios is very difficult,a new approximate but high efficient calculation method based on the pulse sampling in the angle domain is proposed based on.Firstly,a new closed-form solution is derived,as well as an approximate expression for the spatial correlation coefficient under isotropic power angle spectrum,and then the arbitrary non-isotropic angle spectrum is expressed as a weighted summation of 2Duniform sampling pulses.On this basis,the spatial correlation under arbitrary 3Dpropagation scenarios can be equivalent to the weighted sum of the corresponding correlation of each sampling pulse.Simulation results based on the measured Von Mises Fisher distribution show that,when the sampling interval is less than 2°,time consumption of the proposed method is only about 10% of the one of the numerical integral method,and absolute error is less than 0.005,which can be applied on multiple antenna diversity system design,multi-input multi-output system performance evaluation and antenna array flow pattern optimization.