Radio Propagation Characteristics of 40 GHz Band Millimeter-wave on Curved Sections of Railway Environment

In recent years, the use of millimeter-wave bands has been considered for radio communication systems between train and trackside. Millimeter-wave band radio waves are known to have strong linearity and high attenuation on Non-Line-of-Sight (NLoS). On the other hand, it has been reported that they propagate to NLoS by the effects of rails and side walls in sections with side walls and in tunnel sections. Therefore, we simulate to evaluate the influence of side walls in curved sections for the 40 GHz band, which is being considered for use in future mobile communication systems and train radio systems. The simulation results shows that the influence of the side wall tends to be larger, and the path loss tends to be smaller for smaller curve radiuses.