| 摘要 |
<p>PURPOSE:To obtain the sufficiently clear contrast of variable density even in the deep place in soil by amplifying and correcting a received signal so as to supplement the attenuated amount caused by the depth of a concealed place, and forming the image of a cross section based on the signal. CONSTITUTION:The electromagnetic wave emitted from a transmitting antenna 5 is received with a receiving antenna 6. The output is supplied to a high-frequency amplifier circuit 8 through a line 7. The attenuated amount caused by soil, which is a concealed place, is aupplemented by amplifying the output of the antenna 6. In response to the time difference from the time when the transmitted signal is imparted from a pulse generating circuit 4 to the antenna 5 to the time when the output is obtained with the antenna 6, i.e., the depth of the soil 1, the amplification degree is made larger with the increase in depth. The output level of the antenna 6 is corrected more largely. The signals are sampled with a sampler 10 and digitized. The specified processing is performed in a processing circuit 11. Thus, the image of the cross section having the large contrast of variable density is obtained regardless of the depth.</p> |
