Transmission channel analysis for broadband communication over multiconductor UIC cables onboard regional trains

In this contribution, the authors perform a detailed analysis relating to the use of the multiconductor UIC (Union Internationale des Chemins de fer) cables as a broadband data transmission channel onboard regional trains. The analysis is performed evaluating the channel frequency response and the channel capacity as a function of the distance between communication devices, in the 2–30 MHz frequency range of broadband powerline communications. The per unit length (p.u.l.) parameters are measured and simulated in a finite element method (FEM) code, allowing accurate full multiconductor simulations to evaluate the attenuations of the selected channel for communication and the cross-talk between cables. This study has been conducted considering that there are other signals carried by the cable, during regular train operation, and their integrity needs to be taken into account. The results show that, as a matter of fact, UIC cables can be used to transmit high-speed data; this can be exploited for introducing additional facilities (i.e., infotainment, safety features and so on) onboard regional trains, at a reasonably low cost, since no new cabling harnesses need be installed.