| 摘要 |
<p>PURPOSE:To simplify the constitution of a transmitting section by a method wherein a plurality of kinds of markers having different resonance characteristics to a common excitation signal are prepared, one kind of an excitation signal is output from a scanning antenna, the place of the marker is specified from the direction and strength of a received resonance signal, and the kind of the marker is discriminated from the difference of resonance characteristics. CONSTITUTION:A prober is composed of markers 1 and a probe 2, and the markers l are buried integrally with a buried article (such as a buried pipe). Heating wires buried into the buried pipe and used for melting a resin are employed as marker antennas 11, and common resonators 12 and capacitors 13 are mounted in parallel with each antenna 1-1 to 1-3. Rheostats are arranged among the antennas 11 and the capacitors 13 for discriminating the pipe diameters of the buried pipes 3-1 to 3-3, and resistance values are changed so that Q1>Q2>Q3 hold in the sharpness coefficients Q of resonance. Excitation signals having the same frequency are transmitted from a loop antenna 23 for scanning to resonate the resonators 12, and the pipe diameters are discriminated from the sharpness coefficients Q of resonating waves.</p> |
