Measurement and characterization of multiconductor cables in railway signaling systems

Abstract

This thesis presents the measurement and characterization of multiconductor cables used in railway signaling systems. By applying multiconductor transmission line theory to an 푛-wire configuration, this work applies a mathematical formalism for analyzing the behavior of these multiconductor cables through numerical simulations. Aiming to provide a characterization of these cables, this thesis discusses three experimental setups for conducting measurement campaigns both in the laboratory and in the field. These setups cover the measurement of characteristic impedance, scattering parameters, crosstalk frequency response, and additive noise over the frequency range from 20 Hz2 MHz. The dissertation then describes the measurement campaigns performed in both environments. A comparative discussion between results obtained from the simulations based on the adopted model and those from the laboratory and field campaigns shows a high level of agreement. Finally, an analysis of the additive noise power spectral density, together with the magnitude of the frequency response of a single conductor within the multiconductor cable used in railway signaling, confirms that both data communication and sensing can be carried out under certain constraints using low-power electrical signals. The use of low-power electrical signals is an essential requirement to avoid interference with legacy railway signaling systems.