| 摘要 |
<p>PURPOSE:To confirm easily a position of the own station, by utilizing a mobile radio, etc. in which an automobile becomes a mobile station, ena executing a radio wave communication between a fixed station whose position is already known and the own station (mobile station). CONSTITUTION:When an FM modulating signal FO is transmitted from a fixed statin A, an FM modulating signal FO' is sent back synchronously from a mobile station in accordance with said transmission. A distance to the mobile station B is derived in a CPU5, by detecting a beat frequency fR based on a phase difference tR between the transmitting signal FO and the receiving signal FO', and deriving the time required for propagation of the receiving radio wave. A radio wave arrival direction from the mobile station B is measured by a direction finder 2. The CPU5 calculates a relative position of the mobile station B, derives an absolute position of the mobile station B which makes a position of a fixed station A an absolute reference, and transmits it to the mobile station B together with a map signal from a map signal generator 4.</p> |
