Wide-band and narrow-band characterization of the propagation channel in trains

The characteristics of the propagation channel aboard trains are investigated with specific reference to the effects of pantograph arcing onto telecommunication signals, expressed in terms of channel power variations with time, and to the attenuation law governing propagation within cars. Results show that the path loss exponent is slightly smaller than in free space, possibly due to reflections by metal walls, and that it does not depend significantly on the position of transmitter and receiver. It is also shown that the transients generated at the pantograph may pose a threat to telecommunication system's efficiency only if they come in clusters, as the duration of each event is not long enough to affect bit streams. The main application of the study is the investigation of the reliability features of telecommunication systems on board, for both infotainment and safety purposes.