| 摘要 |
<p>PURPOSE:To obtain the accurate detection information of an embedded article, by detecting a reflected wave of every receiving channel to hold the same by a sample holding circuit and removing a DC component from the signal held to said circuit. CONSTITUTION:Radio waves sent out from antennae 1A, 1B are reflected from ground surface and an underground embedded article to be received by antennae 2A, 3A and 2B, 3B and respectively detected by the detectors 7A-7D of channels CH1-CH4. The detection signals outputted from the detectors 7A-7D are respectively inputted to sample holding circuits 8A-8D and held at the detection signal level of a receiving time band of a previous cycle during the non-receiving time band of the reflected waves. The signals outputted from the circuits 8A-8D are inputted to filters 9A-9D to remove DC components thereof to obtain signals of only AC components. That is, ground surface reflected wave components are removed by the filters 9A-9D. The outputs of the filters 9A-9D are inputted to judge devices 10A-10D from which underground embedded article presence signals are in turn outputted.</p> |
