28-GHz High-Speed Train Measurements and Propagation Characteristics Analysis

In this paper, we investigate millimeter-wave propagation characteristics of a high-speed moving train based on field measurements in tunnel and viaduct scenarios. The measurements were carried out at 28 GHz, emulating a 3GPP-like high-speed train (HST) deployment scenario where a transmitter is positioned next to a track and a receiver is mounted on the roof of a train carriage. Path loss (PL) and other channel parameters, including delay spread and Doppler shift, were investigated. One interesting observation is that the path loss, in the tunnel environment, appeared to be independent of distance. We observed that multipath components appeared regularly in the delay profiles, which can be understood due to the regularly installed structural objects, such as overhead power line equipment installed along the track.