Analysis on non-stationary characteristics of wideband radio channel in HSR U-shape cutting scenario

High Speed Railway (HSR) wideband radio channel, as a vital fundamental prerequisite of the research on HSR communication technologies, attracts lots of attention with the tremendous development of HSR in China. The non-stationary characteristic of HSR radio channel caused by the high speed moving of the trains, has been considered as an important and hot research topic. In this paper, a metric of non-stationary characteristic of HSR channel is proposed referring to the theory of non-stationary random signal processing. At an aside, in order to solve the disunity of the index, the normalized non-stationary index is further defined. Then the non-stationary characteristic of HSR U-shape cutting scenario is analyzed by using the proposed metric based on the field wideband radio channel measurement data. The results show that the non-stationary degree of the HSR channel is severe when the varying rate of the Doppler is fast.