A Numerical Technique for Estimating High-Frequency Radiated Emissions from Railway System

Abstract

This article presents a finite-difference time-domain technique to analyze the characteristics of the railway system emission to the outside environment. The 2-D simulation implements algorithms accommodating the interactions of Poisson's equation for the cross-component electrostatic coupling between the train and infrastructure with Maxwell's curl equations accounting for the time-varying wave propagation across the discontinuous boundaries excited by the on-board 400-MHz terrestrial trunked radio system. The 2-D near-field to far-field conversion using the generated surface currents concludes the investigation of system emission characteristics in terms of the radiation pattern and emission level in accordance with the EN 50121-2 criteria. The numerical results of the emission spectrum from 300 MHz to 1 GHz influenced by the integrated railway system components and on-site measurement records during the 750-Vdc metro system integration tests provide a validation of technique for estimating the railway system radiation prior to the start of the system installation phase.