高速铁路平原场景无线信道小尺度衰落特征的研究

研究高速移动条件下无线信道特性是发展高铁新型通信系统的基础。本文基于标准信道探测仪Propsound在高速移动条件下平原场景的无线信道探测数据,分析此场景下的小尺度衰落特征。K因子在列车靠近接收天线时最大值为20dB,远离天线时取值为8dB～10dB;时间色散特性上,多径延时随着列车先靠近又远离接收天线而变化;区别于经典的Doppler功率谱,高速条件下无线信道在列车穿越基站的过程中呈现快速Doppler特性,并无Doppler扩展。

Research on Small-scale Fading Characteristics of Wireless Channels in Rural Aera of High-speed Railway

The research on high speed radio propagation characteristics is the foundation of developing the new kind of high speed railway wireless communication system.In this paper,the data of high speed radio signals in the rural area measured by the convetional channel sounder Propsound are utilized to analyze the characteristics of small-scale fading.The results show as follows: When the train runs close to the base station,the maximized value of Factor K reaches 20dB;when the train runs far away from the base station,the maximized value of the Factor K turns to be 8 dB~10 dB;time dispersion varies with the distance between the transceiver and receiver;as distinct from the classical Doppler spectrum,pure frequency shift and significant Doppler transition are exhibited in high-speed radio channels in the process when the train passes through the base station while no Doppler spread is found.