高速铁路环境下到达角起伏对电波通信的影响

Influence of Angle of Arrival on Radio Communication in High-Speed Railway

无线电波在传播时,由于大气湍流的作用其相位会发生起伏,这是在高速铁路环境中无线通信常常遇到的问题。大气湍流造成不同部分大气的折射率起伏,使得不同部位空间电波具有不同的相移,这些相移导致随机起伏形状的等相面,这种相位形变导致波前到达角的起伏。到达角的起伏会影响通信的质量,尤其是在列车行驶时,到达角起伏会使得有用信号在传输给列车时产生偏移,从而丢失有用信号,既造成通信质量下降也造成能量利用率降低。研究到达角起伏对无线通信的影响,得到了用于描述强弱湍流条件下含有到达角起伏的信噪比的理论模型。同时数值模拟了到达角起伏信噪比和误码率的关系,对实际工程中提高无线通信系统质量具有一定的参考价值。

Due to atmospheric turbulence,spreading radio wave will cause phase fluctuations,which is a problem that are often involved in the wireless communications in high-speed rail environments.This will cause the ups and downs of the refractive index of the different atmosphere parts,so that different space parts of radio wave have different phase shifts,which lead to random fluctuation phase shift shapes and other physiognomy,this phase deformation causes ups and downs of the front wave arrival angle.Arrival angle fluctuations will affect the quality of communication.Especially when train travels,arrival angle fluctuations will make the useful signal shifting when transmitted to the train.While the useful signal is lost,it results in a decline in both the communication quality and the utilization of energy.In this paper,in order to study the impact of arrival angle fluctuations on wireless communications,theoretical model has been used to describe the intensity of turbulent conditions at arrival angle fluctuation SNR.At the same time,we simulate the relationship between arrival angle fluctuation SNR and BER,and provide a certain reference value for practical engineering to improve the quality of the wireless communication system.