Transmitting Devices Near Bus Stops Signals the Bus

When a bus stops at a bus stop, road information comes from the speakers like `this stop is …`

Just a few years ago, driver himself turned the tape player on and off whenever the bus arrives at a stop. Nowadays, bus announces this information automatically using infrared radio communication.

A device transmitting infrared ray (photo above) is installed at the road around 100 m before the bus stop. And a receiving set is fixed on the front side roof of the bus. The receiving set accepts the code of bus stop from the transmitter and announces the information. Sometimes the announcement says, `it is the stop near a certain store`. That is because the infrared radio transmitter is installed at the place.

There is a black clock above the driver. The box signals numbers like `38:12:58` with a beep. The number returns to present time a few seconds later.

The clock is an operation interval set. The sign `38:12:58` means that a bus number 38 passed the stop 12 minutes and 58 seconds ago. Bus driver slow down or speed up after judging from the sign. The wireless communication device named beacon installed at an electric pole or on the top of a building shows the bus when the last bus passed the spot. Using this wireless communication, it is possible to provide people with arrival information service like ` the bus number 6 to arrive 5 minutes later`.

In addition, this wireless communication service can be applied to the missing vehicle location tracking. Police can easily make track for the missing car, which automatically informs its location.

Some electric cars in the golf field have this system in order to keep regular intervals between golfers in a crowded field.

pmiyong@donga.com