Positive signal comparator and method

摘要

A signal comparator receives switch-created signals from two stations manned by an engineer and a trainman in a locomotive and compares the signals for a match. The signals are an implementation and acknowledgement of wayside signals. One station is used to acknowledge a signal and unless a match is determined by the other operator entering the same acknowledgement within a preset time interval the system will automatically stop the train. Alarm functions and speed monitoring functions based on matched station signals are also provided. The system is automatically activated anytime a switch is operated or the speed of the train exceeds 15 mph. Signal matching is also required at period time intervals. If such acknowledgement is not forthcoming, the system assumes crew incapacitation and will automatically stop the train. The system has the capability to require acknowledgement when in proximity of a wayside signal by utilizing global positioning or other navigation system data to determine the location of the train with respect to all wayside signals in the rail system.