JPH042987A - Investigating apparatus of substance buried underground - Google Patents

Abstract

PURPOSE:To make an apparatus small in size, to expand the scope of investigation and also to enable the investigation of a buried substance with no dead angle, by providing a plurality of transmission antennas and by arranging them zigzag so that they overlap each other. CONSTITUTION:A plurality of transmission antennas 12a to 12c are provided and arranged zigzag so that they overlap each other, while a reception antenna 14 being one or more and less than the number of the transmission antennas 12a to 12c is so disposed as to face an array of the transmission antennas. A trigger circuit 32 generates a pulse of a prescribed width at a fixed period and delivers it to transmitters 30a to 30c and a receiver 34. Receiving the pulse, each of the transmitters 30a to 30c generates a transmission wave of a prescribed frequency and they emit the wave simultaneously from the corresponding transmission antennas 12a to 12c into the ground 36. The wave propagates through the ground 36, and when a buried substance 38 exists in the ground 36, a reflected wave therefrom is received by the reception antenna 14. Then, an averager 40 averages a signal inputted from the receiver 34 and removes a noise component therefrom, and the signal is subjected to a signal processing 42 and displayed in a display device 46.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention locates underground water pipes, underground cavities, buried unexploded ordnance, etc. on the ground surface using radio waves. This invention relates to an underground object exploration device for further exploration.

[Conventional technology]

The applicant of the present application has proposed various underground object detection devices that use radio waves to search for underground water pipes and the like from the surface of the earth. As shown in FIG. 8, the conventional underground object exploration device using radio waves has a pair of transmitting antennas 12 and receiving antennas 14 mounted on a movable trolley 10, and moves the trolley 10 in the exploration direction. At the same time, the transmitting antenna 1
2 emits radio waves underground, the reflected waves (echoes) are received by the receiving antenna 14, the depth of the buried object is determined from the propagation time of the radio waves from transmission to reception, and the trolley 10 is moved. The position is determined from the reference point of the buried object by distance.

However, as described above, when searching using a pair of transmitting and receiving antennas, the area that can be searched is extremely narrow, so in order to search a wide area, it is necessary to move the trolley 10 back and forth many times, which takes time. It's not easy. Therefore,
As shown in FIG. 9(A), two underground radars 20a and 20b each having a transmitting antenna and a receiving antenna.
It has been proposed that the search range 22 be expanded by arranging them in a direction perpendicular to the search direction of the trolley. However,
If the two underground radars 20a and 20b are used for exploration side by side, a blind spot 24 will occur between the two radars as shown in FIG. 9(B). In order to eliminate this blind spot 24, three underground radars 20a are installed on the trolley 10 as shown in FIG.
, 20b, and 20C.

[Problems to be Solved by the Invention] As described above, if three underground radars are mounted on the trolley 10 to prevent the occurrence of the blind spot 24, the device becomes very large and difficult to handle. Moreover, radar 20a throughout the area
, 20b, and 20c must be observed simultaneously, which has the drawback of making it difficult to confirm and identify buried objects.

The present invention has been made in order to eliminate the drawbacks of the prior art, and aims to provide an underground object exploration device that is small in size, can widen the exploration range, and does not create blind spots in exploration.

[Means to solve the problem]

In order to achieve the above object, an underground buried object exploration device according to the present invention includes a transmitting section equipped with a transmitting antenna mounted on a moving trolley, and a receiving section equipped with a receiving antenna mounted on the trolley. In the underground buried object exploration device, the reflected wave of a radio wave emitted underground from the transmitting antenna is received by the receiving antenna, and the position of the underground object is detected from the propagation time of the radio wave. The present invention is characterized in that a plurality of antennas are provided and arranged in a staggered manner so as to overlap each other, and one or more of the receiving antennas, which are fewer than the number of transmitting antennas, are arranged to face the transmitting antenna array.

The transmitting unit can be configured to include a plurality of transmitters connected to each of the transmitting antennas, and a transmission controller that sends a control signal to each transmitter to operate each of these transmitters in a time-sharing manner. . The receiving section also performs signal processing to output display signals of different colors to the color display device according to the received signals corresponding to the radio waves emitted by each transmitting antenna, based on the output signal of the receiver connected to the receiving antenna. It is a good idea to provide a container.

[Effect]

In the present invention configured as described above, since the plurality of transmitting antennas are arranged so as to overlap with each other, a wide range can be searched without creating a blind spot. Furthermore, since the number of receiving antennas arranged facing the row of transmitting antennas is smaller than the number of transmitting antennas, the device can be made smaller and less expensive.

If a transmission controller is provided in the transmitter and a plurality of transmitters are operated in a time-sharing manner, the received reflected waves can be easily analyzed. In particular, if a signal processor is installed in the receiving section and an image (echo image) of reflected waves of different colors is displayed on a color display device corresponding to the received signal of the radio waves emitted by each transmitting antenna, the detection It is possible to easily determine which transmitting antenna caused the buried object to be the result of a reflected wave of a radio wave emitted.

〔Example〕

A preferred embodiment of the underground buried object exploration device according to the present invention is as follows:
The details will be explained according to the attached drawings.

FIG. 1 is a plan view schematically showing the main parts of an embodiment of the underground object exploration device of the present invention.

In FIG. 1, on the mobile trolley 10 are three transmitting antennas 12a, 12b, which constitute a transmitting section to be described later.
i2c and one receiving antenna 14 constituting a receiving section to be described later.

The three transmitting antennas 12a, 12b, and 12C are arranged in a zigzag pattern, and two of the three transmitting antennas 12a,
12c is the moving direction of the mobile trolley 10 shown by the arrow 26,
That is, they are arranged side by side in a direction perpendicular to the exploration direction. Further, the transmitting antenna 12b includes the transmitting antenna 12a,
12c, and is located between both transmitting antennas 12a and 12c, so that it overlaps with the transmitting antennas 12a and 12c when viewed from the horizontal direction. On the other hand, the receiving antenna 14 is
On the side opposite to the side where the transmitting antenna 12b of the transmitting antennas 12a and 12c is arranged, the transmitting antenna], 2 b
It is placed in the corresponding position.

As shown in FIG. 2, the transmitter 29 includes the transmitting antenna 1
2a, 12b, 12c and transmitters 30a, 30b, 30C
and a trigger circuit 32, each transmitting antenna 12a,
1.2b, 12c are transmitters 30a, 30b,
It is connected to 30C.

These transmitters 30a, 30b, and 30c simultaneously receive trigger signals from the trigger circuit 32, generate pulsed transmission radio waves, and transmit the corresponding transmission antennas 12a, 12.
b and 12c to fire into the ground at the same time.

The receiving unit 33 includes a receiving antenna 14, a receiver 34, an aherager 40, and a signal processor 42. Detects radio waves reflected from etc. and guides them to the receiver 34. Then, the receiver 34 receives a trigger signal from the I/rigger circuit 32, takes in the reflected wave detected by the receiving antenna 14 in synchronization with this signal, and sends it to the signal processor 42 via the atherager 40.

The signal processor 42 is connected to a storage device 44 such as a floppy disk device and a display device 46 such as a CRT color display, and creates an echo image based on the calculation results obtained according to a predetermined program. It is stored in the storage device 44 and displayed on the display device 46.

The operation of the embodiment configured as described above is as follows.

After the movable trolley 10 is placed at the reference point, it is moved in the direction of arrow 26 in FIG. 1 along an exploration plan line (not shown). The movable dolly 10 is equipped with a distance sensor (not shown), which detects the moving distance of the movable dolly 10 and determines the position of the movable dolly 10 with respect to the reference point.

On the other hand, the trigger circuit 32 generates a pulse of a predetermined width at a predetermined period, and
c and the receiver 34. Each transmitter 30a, 30b
, 30c, when receiving a pulse from the trigger circuit 32, generates a transmission radio wave of a predetermined frequency and transmits the corresponding transmission antenna 1.
Fire from 2a, 12b, and 12c into the underground 36 at the same time.

Radio waves emitted from each transmitting antenna 12a, 12b, 12c propagate underground 36, and if there is a buried object 38 underground 36, for example, as shown in FIGS. 3(A), (B), and (C), The reflected wave (echo) reaches the receiving antenna 14, and is received by the receiving antenna 14 as a composite wave as shown in FIG. 3(D).

When the receiver 34 receives a trigger signal from the trigger circuit 32, the receiver 34 takes in the signal received by the receiving antenna 14, amplifies it, and sends it to the aherager 40. The aherager 40 averages the signals input from the receiver 34 to remove noise components, and sends the averaged signals to the signal processor 42 .

The signal processor 42 generates an echo image of the buried object 38 based on the time when the transmitters 30a, 30b, and 30c emit the transmitted radio waves and the time when the receiver 34 receives the reflected waves, based on a well-known radar equation. The data is stored in the external storage device 44, and the echo image is displayed on the CRT display 46.

In this way, in the embodiment, three transmitting antennas 1
2a, 12b, 12c are arranged so as to overlap each other, and the reflected waves of the radio waves emitted underground from each transmitting antenna 12a, 12b, 12c are transmitted to one receiving antenna 14.
By receiving signals from a wide area, it is possible to search a wide range without creating a blind spot, and the device can be made smaller. Moreover, since only one set of electronic equipment is required in the signal processing section of the receiver 34, the apparatus can be made inexpensive.

FIG. 4 is a block diagram of another embodiment.

In FIG. 4, the transmitter 29 includes transmitters 30a, 30
A transmission controller 50 is provided which sequentially operates the signals 30b and 30c in a time-division manner. This transmission controller 50 consists of a trigger circuit 32 and a distributor 52.

The distribution device 52 receives a trigger signal from the trigger circuit 32 and sequentially switches and operates the transmitters 30a, 30b, and 30c. Further, the distributor 52 inputs a signal selecting a transmitter to be activated to the signal processor 42 . Note that the receiver 33 of this embodiment does not include an averager, and the output signal of the receiver 34 is directly input to the signal processor 42.

The operation of this embodiment configured as described above is as follows.

When the power (not shown) of the underground object exploration device is turned on,
As shown in step 60 of FIG.
outputs a trigger signal to the distributor 52 and the receiver 34 of the receiver 33. The distributor 52 transmits the transmitters 30a, 30b, 30c every time a trigger signal is input from the trigger circuit 32.
are sequentially switched and selected, and a selection signal is sent to the signal processor 42 of the receiving section 33, and an activation signal is sent to the selected transmitter.

That is, when the distributor 52 selects the transmitter 30a,
A signal selecting the transmitter 30a is sent to the signal processor 42, and an activation signal is sent to the transmitter 130a. When the transmitter 30a receives the activation signal from the distributor 52, it generates a pulsed transmission radio wave and emits it into the ground via the transmission antenna 12a (step 62.64).

Similarly, when the distributor 52 selects the transmitter 30b, the selection signal of the transmitter 30b is input to the signal processor 42, and the transmitter 30b sends the transmitted radio waves underground via the transmitting antenna 12b. (Step 62.
66.68). Further, when the transmitter 30c is selected, the selection signal is input to the signal processor 42, and the transmitter 30a emits radio waves underground via the transmitting antenna 12c (steps 62 and 66). .70).

On the other hand, when the trigger signal is input from the trigger circuit 32, the receiver 34 receives the echoes received by the receiving antenna 14 in synchronization with this signal, that is, the transmitting antennas 12a, 12b,
The reflected waves of the radio waves emitted by the radio waves 12c are captured, amplified, and input to the signal processor 42 (step 72).

When a received signal is input from the receiver 34, the signal processor 42 determines which of the transmitters m30a, 30b, and 30c is the source of the radio waves transmitted by the signal. That is, when a transmitter selection signal is input from the distributor 52, the signal processor 42 determines which transmitter the distributor 52 has selected. And signal processor 4
2 is a step in which, when a selection signal selecting the transmitter 30a is received and a reception signal is input from the receiver 34, an echo image is obtained from the reception signal and displayed in yellow shading on the color display device 46. 74.76), step 6
Return to 0.

Further, the signal processor 42 is connected to the transmitter 30b from the distributor 52.
When a signal is input from the receiver 34 when a signal is selected, the echo image is displayed on the color display device 46 in shades of red (steps 74 and 78).
．． 80), return to step 60. Furthermore, the signal processor 4
When receiving the signal selecting the transmitter 30c from the distributor 52, the echo image is displayed on the display device 46 in shades of blue, as shown in step 80, and the process returns to step 60.

Displaying the echo images in different colors as described above, for example,
As shown in the figure, the vertical pixel column 55a of the display device 46 is displayed in yellow, the pixel column 55b is displayed in red, and the pixel column 55c is displayed in blue. In addition, during vertical scanning, interlaced scanning is performed every second scanning line, one screen is formed by three vertical scannings, and each vertical scanning is displayed in yellow, red, and blue. Good too.

When the echo image is displayed in this way, each of the transmitting antennas 12a, 12b,
Because the reflected waves from the radio waves emitted by 12c are strong, yellow, red,
Both blue colors are displayed darkly. For example, if the echo image displayed on the display device 46 has a deep yellow color and a light blue color, it can be easily recognized that a buried object is located below the transmitting antenna 12a.

In this way, in this embodiment, by changing the color of the echo image displayed on the display device 46 in accordance with the reflected waves of the radio waves emitted by the three transmitting antennas 12a, 12b, and 12c, it is possible to It is possible to easily identify whether it is due to the echo of radio waves, and the position of buried objects, etc. can be easily detected.

Note that the echo images resulting from each reflected wave may be displayed without changing color, or may be displayed in black and white.

In each of the above embodiments, a case has been described in which there are three transmitting antennas, but two transmitting antennas may be arranged so as to overlap with each other, or four or more transmitting antennas may be arranged so as to overlap with each other. They may be arranged in a zigzag pattern. Further, as shown in FIG. 7, a plurality of transmitting antennas 12a to 12n are arranged in a staggered manner, and a plurality of receiving antennas 14a to 14, which are smaller than the transmitting antennas, are arranged in a staggered manner.
m may be arranged along one side of the row of transmitting antennas 12a to 12n, facing the row.

〔Effect of the invention〕

As described above, according to the present invention, since the plurality of transmitting antennas are arranged so as to overlap with each other, a wide range can be searched without creating a blind spot. Moreover, since the number of receiving antennas arranged facing the row of transmitting antennas is smaller than the number of transmitting antennas, the device can be made smaller and less expensive.

If a transmission controller is provided in the transmission section and a plurality of transmitters are operated in a time-division manner, it becomes easy to analyze the received signal. In particular, if a signal processor is installed in the receiving section and the display device displays echo images of different colors in accordance with the received signals of the radio waves emitted by each transmitting antenna, it is possible to detect which transmitting antenna the detected buried object is. It can be easily determined whether this is a reflected wave (echo) of the emitted radio wave.

[Brief explanation of drawings]

FIG. 1 is a plan view schematically showing the main parts of an underground object exploration device according to an embodiment of the present invention, FIG. 2 is a block diagram of the configuration of the embodiment, and FIG. 3 is a reflected wave of the embodiment. 4 is a configuration block diagram of another embodiment, FIG. 5 is a flowchart explaining the operation of the embodiment shown in FIG. 4, and FIG. 6 is a waveform diagram with different colors corresponding to each reflected wave. FIG. 7 is a schematic diagram showing the antenna arrangement of another embodiment. FIG. 8 is an explanatory diagram of a conventional underground object exploration device. FIG. 10 is an explanatory diagram of the exploration range when a single underground radar is used, and FIG. 10 is a layout diagram of the underground radar to prevent blind spots from occurring in the conventional exploration range. 10----Movable trolley, 12a to 12c------
Transmitting antenna, 14--Receiving antenna, 29--
One transmitting eye 33----receiving section.

Claims (3)

[Claims] (1) It has a transmitting section equipped with a transmitting antenna mounted on a mobile trolley, and a receiving section equipped with a receiving antenna mounted on the trolley, and the reflected wave of the radio wave emitted from the transmitting antenna toward the ground is transmitted. , in the underground buried object detection device that detects the position of the underground object from the propagation time of radio waves received by the receiving antenna, wherein a plurality of the transmitting antennas are provided and these are arranged in a staggered manner and overlapping each other. An underground object exploration device characterized in that one or more of the receiving antennas, the number of which is smaller than the number of the transmitting antennas, are arranged to face the row of transmitting antennas. (2) The transmitting unit is connected to a plurality of transmitters connected to each of the transmitting antennas, and to each of these transmitters,
Claim 1, further comprising a transmission controller that sends a control signal to each transmitter and operates each transmitter in a time-sharing manner.
The underground object exploration device described in . (3) The receiving section sends display signals of different colors to the color display device according to the received signals corresponding to the radio waves emitted by the respective transmitting antennas, based on the output signals of the receivers connected to the receiving antennas. The underground buried object exploration device according to claim 2, further comprising a signal processor for outputting the signal.