| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To improve accuracy in ground penetration by preventing electromag netic waves from an antenna for ground penetration from leaking to the outside and preventing outside noises from entering. <P>SOLUTION: The antenna is applied with a pulse of 100-1,000 MHz from a transmission circuit 4, radiates electromagnetic waves toward a soil 1, and receives reflected waves from an underground buried object 2, thereby detecting the depth of the object 2, the depth, corresponding to a time from transmission of the pulse to reception of the reflected waves. The antenna is covered with a bottomed housing 86 from an upper part, and the housing 86 is made of iron, and is grounded. A plate made of ferrite is fixed on the inner surface of the housing 86. The antenna is a dipole antenna. <P>COPYRIGHT: (C)2003,JPO</p> |
