The communications systems architecture of the North American advanced train control systems

The communications system that provides for the information flow in the North American advanced train control system (ATCS) is presented in the context of the overall ATCS plan. The features and functions of the nodes in the communications system and their connectivity are defined. The system is based on the OSI model. The protocols used are outlined, with particular emphasis on the radio data link. Special features of the system along with the vehicle-tracking technique are described.<
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