Millimeter Wave Channel Measurements in a Railway Depot

TL;DR

This study provides detailed millimeter wave channel measurements in a railway depot environment at 60GHz, highlighting the impact of antenna orientation and environment on signal characteristics for future railway communication systems.

Contribution

It presents the first comprehensive mmWave channel measurement data in a railway depot, analyzing path loss, delay spread, and K-factor for static and mobile scenarios.

Findings

Signal strength varies significantly with antenna azimuth orientation.

Path loss exponent of 2.04 was observed in LOS conditions.

Delay spreads range from 1ns to 22ns depending on antenna alignment.

Abstract

Millimeter wave (mmWave) communication is a key enabling technology with the potential to deliver high capacity, high peak data rate communications for future railway services. Knowledge of the radio characteristics is of paramount importance for the successful deployment of such systems. In this paper mmWave channel measurements are reported for a railway environment using a wideband channel sounder operating at 60GHz. Highly directional antennas are deployed at both ends of the link. Data is reported for path loss, root mean square (RMS) delay spread and K-factor. Static and mobile measurements are considered. Analysis shows that the signal strength is strongly dependent (up to 25dB) on the azimuth orientation of the directional transmit and receive antennas. A path loss exponent of n=2.04 was extracted from the Line-of-Sight measurements with optimally aligned antennas. RMS delay spreads ranged from 1ns to 22ns depending on antenna alignment. 50% of the measured K-factors were found to be less than 6dB. We conclude this is the result of ground reflections in the vertical Tx-Rx plane.