Communications-based signaling: advanced capability for mainline railroads

Railways utilize signals to maintain a safe distance between trains on the same track, and to safeguard the movement of trains at junctions and crossing paths. Train control is the automatic or manual process of operating safely and efficiently over a railway. While today´s railways operate under many of the same processes as they did fifty years ago, there is the potential for improved operations and safety. This improvement is available through one of the latest advances in train technology-communications-based signaling. In a communications-based signaling (CBS) system, the train achieves operational and safety advantages through the direct exchange of data with wayside, and centrally located, processors. The functional building blocks for a mainline railway CBS system are train locating, train protection, train operation, wayside equipment control, central supervisory control, and data communications. By utilizing a CBS system in an overlay configuration, the advantages inherent in the system are available, while many of the disadvantages associated with upgrading the mainline infrastructure are avoided. Compared to traditional signaling upgrades, installation costs are reduced, operational disruptions are reduced, and life-cycle cost-savings can be realized over the long term. Under such a configuration, the system can be brought on-line incrementally, with new functionality available at each point in the implementation