一种V2V多天线几何去极化信道建模

随着极化相关技术的发展，极化调制在V2V（vehicle-to-vehicle)通信系统中的应用越来越广泛。但由于V2V通信环境复杂，极化调制在V2V通信中会产生去极化效应，从而影响通信质量。为了能够识别去极化效应的大小，提出一种新的基于几何散射理论的V2V多天线极化信道模型。该模型可通过已知的多天线配置、极化场辐射模式及散射体的空间分布，建立去极化效应模型，从而将信道的去极化效应由交叉极化鉴别度——XPD(cross polarization discrimination)的值表示，以拓展极化调制在V2V系统中的使用范围，提高传输速率。实验结果表明，XPD的值受到车辆间距离影响存在阈值，并强烈依赖于到达方位角的分布常数，且当到达方位角的值不同时，改变到达仰角的最大值的大小，XPD值的变化呈固定趋势。因此，本文所提出的多天线几何信道模型，成功的将极化引入多天线的V2V通信，可以为极化域通信的进一步研究奠定基础。

A research on the V2V multi-antenna geometrical depolarization channel modeling

With the development of polarization-related technology, the applied of polarization modulation in V2V communication become more widely. but it will produce the depolarization effect due to the complexity of V2V communication environment, Which seriously affect the communication quality. A new V2V multi-antenna polarization channel model based on the geometric scattering theory is proposed,that be able to identify the size of the polarization effects. The method to establish model of the depolarization effect based on the known antenna configuration, spatial polarization field radiation patterns and the distribution of scatterers, thus indicates the depolarization effect of polarization channel by the values of cross polarization discrimination. It can expand the use of polarization modulation for V2V communication system, and improve the rate of information transmission. Experimental results show that the value of XPD has a a threshold that influenced by the distance between vehicles, and it also strongly dependent on the values of azimuth angle of arrival. Further more, the value of XPD was changed to a fixed trend if change the values of the maximum of elevation angle of arrival when the azimuth angle of arrival in different values. Therefore, the multi-antenna geometry channel model presented in this paper has introduce the polarization in V2V communications and lay the foundation for further research on polarization communication.