| 摘要 |
A vehicle-mounted communications device (2) comprises: a position detection unit (7) that detects the current position of a vehicle; a radio wave state detection unit (5) that detects the radio wave state of a communications network (3); and information transmission units (133, 134) that send information about the current position of the vehicle and information about the radio wave state of the communications network (3), to an information center (4). The vehicle-mounted communications device (2) comprises: an out-of-range information reception unit (135) that receives out-of-range information sent from the information center (4) and indicating an out-of-range area for the communications network (3); and an approach determination unit (15) that determines whether or not the vehicle has approached the out-of-range area for the communications network (3), on the basis of the information about the current position of the vehicle and the out-of-range information. |
