三维统计信道中的多普勒效应及其信号分析

Doppler Effect and Analysis of Signals in Three-dimensional Channel Model

在三维(3Dimensional,3D)空间域无线通信信道建模中,针对不同环境中仰角(Elevation Angle,EA)分布的复杂性,提出一种指数型概率分布,然后对这种分布下的无线信道进行建模,最后对接收端的多普勒功率谱密度(Power Spectral Density,PSD)和信号特性进行分析与仿真。采用近似算法推导出多普勒PSD的解析式,同时对Rayleigh衰落信道中接收信号包络、平方包络的功率谱及时延相位差的概率密度函数进行研究。实验结果表明,所提出的三维无线信道模型在进行参数估计时符合相关理论与实际经验,同时指数函数模型的单变量特性使其在适应不同实际信道环境时非常灵活,因此可以对多种无线信道环境下的信道特征进行参数估计。

In the modeling of three dimensional （3D） wireless communication channels,an exponential probability densi- ty function for elevation angle （EA） distributions in different environments was proposed in this paper and then the wireless channels were implemented under this distribution. Furthermore, this paper simulated and analyzed the Doppler power spectrum density （PSD） and signal characteristics of terminals. This paper derived closed form expressions for Doppler PSDs by using approximate algorithm. Meanwhile, the PSDs of envelope and squared envelope of arrival signals and probability density function of delay phase difference in a Rayleigh fading channel are investigated. Simulation re suhs show that the channel parameter estimation of this model satisfies reference theories and practical experiences. In addition, it has a singular variable which is benefit to adapt to different actual channel environments. The model which we provided can be applied to parameter estimation of multiple wireless communication environments.