ABSTRACT
The signalling system within the Channel Tunnel has to cope with the sort of train frequencies normally found on a busy urban passenger railway, with the added complication that a mix of trains with differing maximum speeds and performance must be accommodated. This blend of traffic at fairly high speed and close headways, together with exceptionally stringent safety requirements arising from the length of the Tunnel, has led to many special measures being taken when designing the signalling and train control systems. Some features differ from normal railway practice.
