| 摘要 |
<p>A railway network monitoring system monitors the position and speed of a train (1) on a track (2). An aerial (3) and receiver (4) receive signals from earth satellites of a global positioning system, for example the Navstar System. The signals are passed to a processor (5) which determines the location of the train (1). The speed of the train (1) is measured by a speed sensor (6) and the measured value is input to the processor (5). The processor (5) accesses a digitally coded information from a data store (7) of a map of the train's route and associated speed data. The processor (5) then compares the train's determined location with the map and compares the known speed of the train (1) with the maximum permissible speed programmed into the data store for that particular location. The train's location, speed and difference from the maximum allowed are displayed on a visual display unit (8). If the train (1) is exceeding the allowed maximum on alarm (9) is activated to warn the driver. If the train (1) is exceeding the speed limit by a predetermined margin the power is reduced and/or the brakes applied by a power control unit (10) and brake control unit (11) respectively.</p> |
