| 摘要 |
PURPOSE:To detect the direction of a transmission source in good preciseness, by receiving ultrasonic waves formed by modulating low frequency signal waves from three definite point on the running surface of a moving body with a high frequency carrier wave by a pair of the left and the right wave receiving elements on the moving body to perform phase comparison. CONSTITUTION:A synthesized wave of a low frequency signal wave component and a carrier high frequency wave component in an FM wave received by a pair of a left and a right wave receiving elements is generated and phase difference is detected by a phase difference detector to drive a motor and a wave receiver is directed to a phase difference reducing direction. Low frequency signal wave components obtained as the outputs of a pair of FM demodulators are compared to almost direct the wave receiver to the direction of a transmission source and the phase of a carrier high frequency wave component having a short wavelength is compared to be able to direct said wave receiver to an accurate direction. The direction of the transmission source can be known on the basis of the output of a potentiometer for detecting the rotary angle of the motor by an operation control apparatus. |
