三维空间域多径信道模型的AOA和TOA特性分析

Analysis of the AOA and TOA properties of the 3D spheroid model

在三维空间域提出了一个几何模型,其散射椭圆半球体的中心在移动台(MS),基站(BS)被置于散射球体外部。该模型可以在方位角和仰角平面同时描述多径波的到达角度和到达时延,据此推导出电磁信号分别在MS和BS端关于到达角度的联合、边缘概率密度函数封闭式表达式。除此之外还推导出到达时延的联合概率密度函数的封闭式表达式。该三维模型适用于低MS天线和高BS天线且重要散射体分布在移动台附近的室外宏蜂窝通信环境。此外还对数值仿真实验获得的理论数据进行分析比较,进一步验证信道参数估计结果符合理论和经验。

A three-dimensional（3D） geometric model is presented with a mobile station（MS） located at the center of a 3D scattering semi-spheroid and a base station （BS） located outside of the semi-spheroid. The presented model can describe simultaneously angle of arrival and time of arrival of muhipath waves in the azimuth and elevation planes. Closed-form expressions for joint and marginal probability density functions（pdfs） of the angle of arrival are provided as seen from the mobile station and base station are derived. Furthermore, closed-form expressions for joint pdfs of the time of arrival observed at the MS and the BS in correspondence with azimuth and elevation angles are derived. The model is suitable in a macro-cellular environment with a low MS and an elevated base station antenna, where significant scatterers are distributed about the former. Moreover, the obtained theoretical results with some 3D scattering models are compared further to validate the rationality of the proposed model.