| 摘要 |
<p>PURPOSE:To accurately measure the position of a target by measuring the radio wave propagation time between the transmitting antenna and receiving antenna arranged in a pit in a vertical direction and measuring the permitivity of the soil from ground surface to the vicinity of the target. CONSTITUTION:A microcomputer (MC) 133 measures the time from the emission of the radio wave sent from a synchronous circuit to the reception of a surface propagation wave. Next, the MC 133 calculates the speed of the surface propagation wave using the preliminarily inputted distance between a transmitting antenna T and a receiving antenna R and also calculates the permitivity of the soil at the point of the antennae from the ratio of the speed of the surface propagation wave and the preliminarily inputted propagation speed of a radio wave in air. In measuring this permitivity, a cylindrical insulating case 101 is moved, for example, by 1cm in the vertical direction and the permitivity is read to be stored in a memory. Therefore, the MC 133 stores permitivity at each position. By this method, the propagation speed in each stratum of the radio wave plying between ground surface and a target can be known and the distance up to the target, that is, the depth of the target can be accurately measured.</p> |
