Electric railway traction. V. Train detection, communications and supervision

This article describes systems in use for railway control and communications, and surveys current developments. This article describes the hardware necessary for detecting the position of trains and transmitting information between trains and track control systems. This equipment includes track circuits, transponders and beacons, track conductors, and freespace radio. The implementation of automatic train control systems as a hierarchical process is also covered and the article concludes with a summary of applications of computers and information technology in sophisticated integrated control centres with an overview of the development of the North American Advanced Train Control System (ATCS) and the European Train Control System (ETCS).