| 摘要 |
<p>PURPOSE:To apply high sensibility and high stability, and to make unnecessary an extra cable between a transmitting side and a receiving side by obtaining a detecting signal with sending a synchronizing signal in a frequency range from a receiver side to a transmitter side and with mixing it to a resonant frequency signal, and obtaining a receiving output to be detected with the mixture of the received detecting signal and the synchronizing signal. CONSTITUTION:The synchronizing signal in a frequency range f1+ or -fa-f2+ or -fa is generated on the receiver side, and transmitted to the transmitter side. The synchronizing signal is mixed with a signal at fa on the transmitter side. The synchronizing signal is mixed with a signal at fa on the transmitter side, and the detecting signal in f1-f2 is obtained. Next, the detecting signal is sent to a check point, and it is received on the receiver side. The received detecting signal is mixed with the same signal as the synchronizing signal in f1+ or -fa-f2+ or -fa, and detected as the signal at only fa. Thus, the device possesses the high sensibility and high stability, and it does not require the extra cable between the transmitter side and the receiver side.</p> |
