A train control system includes positioning systems at the end of the train
and at the front of the train, allowing the conductor or engineer to
unambiguously determine that no cars of the train have become detached.
The positioning system at the end of the train is also used to verify that
the entire train has cleared a block. This information can be relayed to a
dispatcher, thereby eliminating the need for trackside sensing equipment.
A control unit prevents the train from moving without an authorization
that includes the train's current position.
