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.