VEHICLE POSITION RECOGNITION DEVICE AND ITS RECEPTION LEVEL ADJUSTER ON VEHICLE SIDE

摘要

PROBLEM TO BE SOLVED: To enhance the detection precision in a vehicle position recognition device by an electromagnetic induction connection system of a road side resonance circuit and a vehicle side resonance antenna. SOLUTION: This device is a vehicle position recognition device which is equipped with a road side resonance circuit 10, a vehicle side resonance antenna 20 consisting of a resonance circuit a resonance frequency of which is the same as that of the rode side resonance circuit 10, and a transmission/reception means 30 including an oscillation circuit 32 and a demodulation circuit 34, and recognizes a current position of a vehicle V with an installation position of the rode side resonance circuit 10 as a reference by a voltage change occurring to the vehicle side resonance antenna 20 by electromagnetic induction connection with the rode side resonance circuit 10. The S/N of a reception signal received by the vehicle side resonance antenna 20 is enhanced by demodulating a carrier wave to be transmitted from the vehicle side by the road side resonance circuit 10.