Abstract
Modern rail and particularly automated train systems utilize train control schemes which rely on continuous onboard-wayside wireless communication in the UHF/SHF frequency bands. The knowledge of radio propagation process and propagation environment are essential for specification, design, installation, and optimization of the cited wireless communication systems. To this end, radio propagation prediction models are applied which are normally characterized by the radio environment as a function of frequency and distance between transmitter and receiver along with electromagnetic characteristics of the propagation environment. These radio propagation models typically predict received power level or path loss profile for specific transmitter and receiver location. A railway tunnel offers a common and complex radio propagation scenario for automated train control applications with strict radio-based data communication subsystem requirements.
In this research, special attention has been given to the case of theoretical modeling of the UHF/SHF radio propagation process inside curved multi-section inhomogeneous tunnels. The theoretical results are compared to the measurement data collected through an extensive field validation campaign conducted in the Toronto Transit Commission (TTC) subway tunnels.
