Warning trackside workers of approaching train - using portable warning devices which receive time division multiplexed information and evaluate respective address codes

摘要

A lineside cable (5), featuring a number of fixed interface units (11,13,15) is laid between adjoining signal boxes (1,3). Each fixed interface unit has a unique address code and can accept a portable warning unit (17,23). Data transmissions containing an address code for a partic. interface unit and warning information pertaining to trains approaching that unit are time-division-multiplexed down the lineside cable. The portable warning unit compares each multiplexed transmission address code with its own fixed interface address code, and displays the train warning information should the two match, thus giving accurate information about approaching trains. The system is also capable of using inductive, radio or fibre-optic transmission media. ADVANTAGE - Does not require manual acknowledgement of warning message. Speeds up railway traffic.