How does the bus arrival information system work?
Buses must be equipped with an Automatic Vehicle Location transmitter, which can track the bus, using a Global Positioning System (GPS) and transmit the data in a standard protocol. On-board software predicts the arrival time at the next bus stop. This information is then sent to a screen at a transport stop or the App through a central control system. The screen at the bus stop counts down the minutes until the bus arrives. Updates are usually received from the vehicle location system at 30 second intervals, so information on the signs is regularly updated.