| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical beacon which is multi-rate compatible in the uplink direction and is capable of increasing the chances of properly receiving high-speed frames transmitted after low-speed frames.SOLUTION: The present invention relates to an optical beacon 4 that wirelessly communicates with vehicle-mounted devices 2 on traveling vehicles 20 using an optical signal. The optical beacon 4 includes; an optical receiver unit 11 capable of making photoelectric conversion at two transmission rates (high and low); an optical transmitter unit 10 capable of making electro-optical conversion at a predetermined transmission rate; and a communication control unit 7 configured to perform a storage process for storing a vehicle ID contained in a low-speed frame UL1 received by the optical receiver unit 11 in a downlink frame DL2 to be transmitted by the optical transmitter unit 10. The communication control unit 7 is capable of performing a standby process for postponing execution of the storage process until a predetermined condition is met.SELECTED DRAWING: Figure 12 |
