| 摘要 |
<p>Pulse waves having a peak value are periodically radiated from a pulse generator (4) into the ground (5) through the surface (1). The waves reflected by the materials (8A,8B) buried under the ground are trapped at the ground surface (1). The reflected waves corresponding to the pulse waves are amplified through a high-frequency amplifier (9) at a degree that increases for each pulse radiation. The outputs of the high-frequency amplifier (9) are (11) at moments that are successively delayed each by a predetermined period of time on the basis of the individual radiation timings of pulse waves, thus obtaining low-frequency signals whose time axes of pulse waves are extended. Waveforms of the low-frequency signals are displayed on a waveform display unit (12). Presence or absence of materials (8A,8B) buried under the ground is detected on the screen of the waveform display unit (12) relying upon the presence of peaks in the low-frequency signals reflected by the materials (8A,8B) buried under the ground, and the depth of the materials (8A,8B) buried under the ground is detected depending upon the timings at which the peaks appear.</p> |
