| 摘要 |
PURPOSE:To detect the position of a vehicle extending over a wide range without installing newly a fixed station, by calculating the absolute present running position of the vehicle, based on position information in a radio wave transmitted from a stationary satellite, and an arrival direction, and handling it as the correct value of a relative present running position. CONSTITUTION:In accordance with a timing signal 114 from a circuit 26, a transmitter-receiver 14 transmits an inquiry signal 106, and receives a radio wave signal 104 sent from stationary satellites S1-S3 in accordance with it. From its signal, a decoder circuit 42 detects the installation of the satellite and the arrival direction, and stores them in a storing circuit 44 in accordance with the timing signal 114. An absolute position calculating circuit 46 calculates an absolute present running position, based on position information of the satellites S1-S3 stored in the storing circuit 44, the arrival direction of the radio wave signal 104, and the vehicle advance direction based on the north polar point as a reference. From its position signal, a present position correcting circuit 34 executes the correction of the relative present running position. |
