Effect on the Propagation Characteristics of the Electromagnetic Waves by the Second-order Radiation of the Moving High-speed Train

• Published in: 电子学报：英文版 2013-10, Vol.22 (4), p.865-870
• Main Author: WEN Yinghong MA Yunshuang WANG Jian ZHANG Xiaoyan
• Format: Article
• Language: English
• Subjects: 二阶; 传播特性; 入射角度; 发送频率; 电磁波; 移动; 辐射频率; 高速列车
• ISSN: 1022-4653

The effect on the propagation characteris- tics of the electromagnetic waves by the second-order ra- diation of the moving high-speed train is analyzed in this paper. Two Lorentz transformations, one from the sta- tionary reference coordinate system to the moving system and the other vice versa, are employed to derive the the- oretical model for analysis of the propagation characteris- tics of the vertical polarized plane time-harmonic waves, which is oblique incidence to the train. The calculation re- suits show that for the transmitting wave reflected by the moving high-speed train, two main signals can be received. One is at the transmitting frequency and the other is at the second-order radiated frequency. The frequency spectrum between these two frequencies are much larger than which is introduced by the Doppler shift. The frequency and the reflection angle of the reflected wave are no longer equal to the frequency and the incident angle of the incident wave. The changed reflection frequency and angle are related to the train＇s velocity, the incident angle and the azimuth an- gle of the incident wave. The frequency shift is mainly decided by the y-component of the train＇s velocity. It has nothing to do with y-component of the train＇s velocity. The reflection angles will be smaller than the related incident angles when the train goes along --y direction. The reflec- tion angles will be larger than the related incident angles when the train goes along ＋y direction. The reflection an- gle will become larger and larger with the increase of the incident angle and the y-component of the train＇s velocity. The induced current density and the charge density on the surface of the train are increased with the train＇s velocity, and the induced charge is much smaller than the induced current.