| 摘要 |
PURPOSE:To make the period of position detection of a moving body equal to that of the conductor of a line by conducting an AC current different in a frequency to two antennas to excite an inductive radio line and detecting linearly the respective voltages of the frequencies induced between three conductors and a linear conductor to obtain an envelope and operating them. CONSTITUTION:When a magnetic field is generated by the antennas which are excited by high frequency power sources having the frequencies f1 and f2, the voltages corresponding to individual frequencies are induced between the conductors 11, 12, 13, and 14. The voltages of individual frequencies induced between the conductors 11 and 14, conductors 12 and 14, and conductors 13 and 14 are received selectively and are subjected to signal processings in a signal processings device, which is provided in the terminal of a line 15, as follows; the voltage of the frequency f1 between the conductors 11 and 14 is eliminated for a noise voltage by a band-pass filter 21-1a and is detected linearly by a detector 22-1a and is led to an AD converter 23-1a. The voltages between the conductors 12 and 14 and conductors 13 and 14 are led to the AD converters 23-2a and 23-3a similarly. The voltages of the frequency f2 are led to the AD converters 23-1b, 23-2b, and 23-3b similarly. |
