JPS61114179A - Investigation radar device - Google Patents

Abstract

PURPOSE:To decide the kind of a target by calculating the guidance rate of the target from the transmission and reception times, and transmission and reception electric power of a transmitting and receiving antenna and a receiving antenna, the distance between both antennas, etc. CONSTITUTION:A radio wave whose radiation electric power is specified is radiated by a transmitter 1 and the transmitting and receiving antenna 2a and a reflected wave from the target 5 buried under the ground is received by the antenna 2a and receiving antenna 2b at specific distance from the antenna 2a and then processed by a receiver 3. A computing element 4 determines the transmission and reception times, and transmission and reception electric power of the antennas 2a and 2b according to the output of the receiver 3, and the dielectric constant of the target 5 is calculated on the basis of the distance between the antennas 2a and 2b to identify not only the position of the underground buried target, but also the kind of the target.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an exploration radar device for exploring underground objects, and particularly to a device capable of determining the type of underground objects.

[Conventional technology]

A conventional device of this type will be explained based on the underground object detection radar shown in FIG. 2. In the figure, (1) generates radio waves and transmits them from an antenna (2).

A transmitter, (3) a receiver that receives reflected waves via an antenna (2), (4) a signal processor, and (5) a target buried underground to be explored.

Next, to explain the operation, the radio waves emitted from the transmitter (1) are radiated underground through the antenna (2) and reach the target (5), and the arriving radio waves reach the target (5). and received by the antenna (2). This received wave is processed by a receiver (3) and a signal processor (4) to measure the presence or absence of a target (5) and its position.

[Problem that the invention seeks to solve]

Since the conventional underground object detection radar device was configured as described above, it only had the function of detecting the location and depth of the underground object (5), and could not detect the type of the underground object (5). It also has the disadvantage that it cannot be distinguished.

This invention was made in order to eliminate the problem of slope, and aims to make it possible to determine the type of underground object (5) other than its position and depth. .

Means for Solving Problem C] This invention separates the transmitting and receiving antennas at a predetermined distance and measures the transmitting power and receiving power, thereby determining the electrical constants of the underground medium and the target object. , and to provide a device that can determine the type.

〔Example〕

The following explanation will be given based on the embodiment shown in FIG.
2a) is the first antenna that transmits and receives radio waves as radiated power P8 and reflected power PRI; (2b) is the first antenna (2a
), the second antenna (3') receives the reflected power P0 at a distance X from the
b) The position of the underground object (5) from the reflected wave obtained from
In addition to measuring the depth, this is a signal processing computer that can also process and determine the type of underground objects (5).

Next, to explain the operation, when the radio wave from the transmitter (1) is radiated by the first antenna (2&) as power P8, the reflected wave from the underground object (5) is transmitted to the first antenna (2&). While it is received as power PRI, it is received as power PIT by the second antenna (2b).

Since the distance between the first antenna (2a) and the second antenna (2b) is X1 and the depth of the underground object (5) is Y, now,
The reflectance of the underground object (5) is F1, the attenuation rate of radio waves underground is α, the underground permittivity is tl, and the permittivity of the underground object (5) is wo!
,...■ Also, the first. The time from when the radio waves received by the second antennas (2a) and (2b) are transmitted is tl, respectively.

'I, the speed of radio waves in free space 1c, the following relational expression holds true.

Therefore, from each of the above equations, can be obtained.

Therefore, the depth of the underground object (5) can be calculated from the 0 formula, and the geology can be calculated from the underground dielectric constant (tl) obtained by the 0 formula, and the dielectric constant of the underground object (5) in the 0 formula The type can be determined from (ε,).

From these points, 1. Second antenna (4a).

(4b) Distance between, transmission power P, and reception power pHl
PRl, and their respective arrival times f1. By calculating the measured value of tl by the signal processing computer (3'), the position of the underground object (5) can be known and the type can be determined.

Note that in the above embodiment, the first. 2nd antenna (2a)
, (2b) shows the case where two antennas are used, but if the underground permittivity (ε1) is known in advance, the permittivity (ε, ) of the buried object can be found even if there is only one antenna. This allows the type of underground object (5) to be determined.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to obtain an exploration radar device capable of determining the type of object to be explored for the position of a target buried underground.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an underground object detection radar according to the present invention, and FIG. 2 is a diagram corresponding to FIG. 1 showing a conventional underground object detection radar. (1) is the transmitter, (2) is the transmitting and receiving antenna, (2a) is the first antenna, (2b) is the second antenna, (3) is the receiver, (3) is the computing device, (4) is the signal processing machine, (5) is a target.

Claims (1)

[Claims] In an exploration radar device that searches for a target by emitting radio waves to a target and receiving the reflected waves, there is provided a first antenna that emits radio waves to the target and receives the reflected waves; and a second antenna arranged at a predetermined distance apart and receiving reflected waves from the target object, and data on each required transmission/reception time, transmission/reception power, and distance between these two antennas obtained from the first antenna and the second antenna. An exploration radar device comprising: a calculation processing unit that calculates the dielectric constant of the target object by performing calculation processing as a signal and determines the type of the target object.