| 摘要 |
PROBLEM TO BE SOLVED: To provide a radio communication system and a radio communication system ranging method that are capable of measuring a distance to a radio communication terminal even when using general purpose radio communication.SOLUTION: A radio communication system performs wireless communication between an on-vehicle communication device 10 mounted on a vehicle 100 and a portable wireless communication terminal 11 and thereby detects a relative distance between them. The on-vehicle communication device 10 transmits an output intensity keeping request that requests the portable wireless communication terminal 11 to keep its transmission radio wave intensity at constant intensity, and calculates a distance to the portable wireless communication terminal 11 on the basis of reception radio wave intensity of a response signal transmitted at the constant intensity from the portable wireless communication terminal 11. |
