CN203838349U - Single-hole directional geological radar used for tunnel advanced geological exploration - Google Patents

Abstract

The utility model discloses a single-hole directional geological radar used for tunnel advanced geological exploration. The single-hole directional geological radar comprises a radar antenna housing, a high-performance emission antenna, an orthogonal directional receiving antenna, and electromagnetic wave emitting, receiving and processing circuits. The front end and the rear end of the radar antenna housing are respectively provided with a front protective cover and a rear protective cover in a fixed or movable way. The high-performance emission antenna emitting electromagnetic waves, the orthogonal directional receiving antenna, and the electromagnetic wave emitting, receiving and processing circuits are arranged inside the radar antenna housing. The orthogonal directional receiving antenna sends received electromagnetic waves to the electromagnetic wave receiving circuit. The electromagnetic waves are further sent to electromagnetic wave processing circuit. The body of the orthogonal directional receiving antenna is divided into four parts through separator plates. Each part has a receiving antenna unit arranged therein. Four independent receiving units with phase differences are then formed. The single-hole directional geological radar can achieve precise geological condition searching within a certain range around a drill hole and also realize accurate azimuth angle positioning.

Description

The directed geological radar of a kind of single hole of surveying for tunnel geological

Technical field

The utility model relates to the directed geological radar of a kind of single hole, relates in particular to the directed geological radar of a kind of single hole of surveying for tunnel geological.

Background technology

Borehole radar method is a kind of wide spectrum electromagnetic technique that descends definitely dielectric distribution, by emitting antenna with receiving antenna is all placed in same boring and spacing is fixed, according to the electromagnetic two way travel time of receiving end, amplitude and waveform information, can infer the architectural feature that underground rock soil medium.The decipher of borehole radar is in the georadar image section of gained after data processing, according to the waveform of reflection wave groups and strength characteristic, by the tracking of lineups, determines the geologic feature of reflection wave groups.Advance boreholes radar is regarded as the one advanced prediction method that becomes more meticulous, and is usually used in during tunnel geological surveys.It is to utilize the means such as probing that tunnel geological is surveyed, try hard to grasp rock soil structures, character, the state in front before construction, and the geological information such as situation and terrestrial stress situation is deposited in the tax of underground water, gas etc., instruct and avoid occurring geologic hazard for further constructing to provide, ensure construction safety, carry out smoothly.

The conventional antenna of borehole radar is dipole antenna, its energy radiation and reception are from the signal in 360 ° of spaces, the very difficult orientation of determining reflecting body of data that generally utilizes single hole radar to record, and can only determine the distance of reflecting body, therefore greatly reduce the practicality of single hole borehole radar, cause single hole borehole radar do not get the nod so far in actual applications and promote.In order to estimate the orientation of reflecting body, at least need the data of 2 borings, and at engineering site, often due to the restriction of room and time factor, only can in one borehole, measure, therefore in the urgent need to a kind of single hole directional drilling radar, for engineering practice provides new solution.

The beginning of the eighties in last century, in the world begin one's study boring geologic radar detection technology and instrument of many mechanisms.MALA company of Sweden has developed RAMAC single hole boring beam radar, RAMAC radar has adopted many receiving antennas and has communicated by optical fiber and radar host computer, but because boring is very dark, in the time that radar carries out photosignal conversion and distant signal transmission, the reasons such as data delay have inevitably caused the transmission of multipath reception signal asynchronous, aspect system time precision, there is defect in RAMAC radar, cause in Practical Project the position angle Effect on Detecting to anomalous body unsatisfactory, therefore, RAMAC single hole boring beam radar is not promoted and stops production, and the current single hole boring beam radar equipment that there is no in the world moulding.

In sum, there are following two problems in single hole boring geological radar: (1) conventional single hole borehole radar can only be determined the distance of reflecting body, cannot directed provide the position angle of geologic anomaly body; (2) the directed geological radar of existing single hole has problems aspect system time precision, and in Practical Project, orientation accuracy is poor.

Utility model content

The purpose of this utility model is exactly in order to address the above problem, and provides a kind of single hole of surveying for tunnel geological directed geological radar, and it has, and geologic anomaly body angle orientation precision is high, system time precision advantages of higher.

To achieve these goals, the utility model adopts following technical scheme:

The directed geological radar of a kind of single hole of surveying for tunnel geological, comprise radar antenna shell, high-performance emitting antenna, orthogonal directed receiving antenna and electromagnetic wave transmitting, receive and treatment circuit, before the rear and front end of described radar antenna shell installs additional by fixing or manner respectively, rear protective cover, described radar antenna enclosure is equipped with the high-performance emitting antenna of emitting electromagnetic wave, orthogonal directed receiving antenna and electromagnetic wave transmitting, receive and treatment circuit, described orthogonal directed receiving antenna is sent the electromagnetic wave receiving into electromagnetic wave receiving circuit, again described electromagnetic wave is sent into electromagnetic wave treatment circuit, described orthogonal directed receiving antenna body adopts dividing plate to be divided into 4 parts, a receiving antenna unit is set in every part, form dephased four receiving elements independently of tool.

Described radar shell is fiberglass cylinder.

Described forward and backward protective cover is streamlined.

Described high-performance emitting antenna adopts dipole emitting antenna.

Described orthogonal directed receiving antenna comprises the receiving antenna unit of four alumina based materials that adopt the antenna casing of fiber reinforced plastic barrel, are divided into through dividing plate and is positioned at the concentric cable that transmits and receive signal for transmitting radar wave of dividing plate intersection, outside the receiving antenna unit loading with resistance of described employing dipole antenna, be provided with the antenna element shell that adopts ambroin, described dividing plate adopts ambroin.

In described dipole antenna, every antenna length is 1/4 wavelength, and centre is the filled media of high-k, the orthogonal placement of two electrode couple sub antennas.

Described radar electromagnetic wave radiating circuit comprises MCU control module I, sine-wave generator, amplifier, frequency sampling circuit, modulation circuit, synchronization control circuit, power amplifier and emitting antenna, adopt MCU control module I to control sine-wave generator and produce the transformable sine wave signal of wide-band, by amplifier, described sine wave signal is amplified, and feed back to MCU control module I adjustment sine wave signal frequency by frequency sampling circuit; MCU control module I produces pulse width signal modulation by synchro control modulation circuit simultaneously, and carrier modulation is become to pulse signal and is input to emitting antenna through two stage power amplifier.

Described radar electromagnetic wave receives and treatment circuit comprises independently receiving element of 4 tunnels, 1 MCU control module II and 1 FPGA processing unit, the signal of reflection of electromagnetic wave is through independently receiving element of 4 tunnels, tuning through 4 tunnels again, filtering, sampling and amplifying circuit receive the echo of corresponding transmission frequency, MCU control module II regulates the parameter of tuned circuit, screw filter carries out filtering to high frequency reflected signal, carry out signal amplification by radio-frequency amplifier again, then send into difference frequency sample circuit, difference frequency sample circuit carries out mixing output intermediate-freuqncy signal to the 220Hz local oscillation signal of high-frequency signal and the generation of MCU control trigger controller, intermediate-freuqncy signal enters A/D converter conversion after low-frequency amplifier amplifies again, transformation result is sent into MCU control module II and is processed.

Described FPGA processing unit adopts high speed processor based on FPGA and the design proposal of the 4 synchronous A/D converters in tunnel, and use digital circuit synchronous logic technology and data fifo buffer technology, the data of FPGA processing unit after to A/D sample conversion device store and pre-service, and by communications optical cable by pretreated digital data transmission to industry control host computer.

Utilize the directed geological radar of the above-mentioned single hole of surveying for tunnel geological, calculate the poorly incident angle of plastid reflection wave by Optimum Theory, its objective function is as follows:

$\mathrm{\Φ}\left({\mathrm{\α}}_i\right)=\underset{i=i_1}{\overset{i_2}{\mathrm{\Σ}}}{(v_i\cos {\mathrm{\α}}_i+h_i\sin {\mathrm{\α}}_i)}^2$

Wherein Φ is ceiling capacity, the incident angle that α is reflection wave, and v is the signal on boring vertical plane, and h is the signal on boring length direction, and i is i sub-sampling.

The beneficial effects of the utility model:

1 the utility model has designed the design proposal of the directed geological radar of a kind of single hole based on orthogonal directed receiving antenna, by 4 independently dipole receiving antenna unit form, by measuring the information such as four phase differential, can realize boring around in certain limit the meticulous of geological condition detect and azimuthal accurate location;

2 the utility model are in the inner integrated radar signal of radar antenna, receive, digital signal conversion and processing module, use high-speed a/d to gather the signal that radar receives, by high speed FPGA, data are stored and pre-service, finally by optical cable by pretreated jamproof digital data transmission to host computer, reduce to greatest extent the interference that high frequency analog signals may be subject in the time of transmission, and reduce volume of transmitted data and long range signals and transmitted the signal delay that may cause, ensure that radar-probing system has very high time resolution, thereby ensure the precision of geologic anomaly body angle orientation,

3 radar signal trigger circuit of the present utility model adopt MCU control module, feed back to MCU control module adjust sine wave signal frequency by frequency sampling module, realize occurrence frequency accurately controlled, can radar are operated under optimum frequency according to actual conditions; In radar signal receiving circuit, MCU control module can regulate the parameter of tuned circuit, improves to greatest extent the receiving sensitivity of radar signal.

Brief description of the drawings

Fig. 1 is the orthogonal directed receiving antenna structural representation of the utility model;

Fig. 2 is the orthogonal directed receiving antenna cross-sectional view of the utility model;

Fig. 3 is the utility model electromagnetic wave trigger circuit theory diagrams;

Fig. 4 is that the utility model electromagnetic wave receives and treatment circuit theory diagram;

Fig. 5 is the utility model one-piece construction schematic diagram.

In figure: 1. antenna casing, 2. dividing plate, 3. filled media, 4. antenna element shell, 5. antenna element, 6. concentric cable, 7. sine-wave generator, 8. amplifier, 9. modulation circuit, 10. power amplifier, 11. synchronization control circuits, 12. frequency sampling circuit, 13.MCU control module I, 14. emitting antennas, 15. receiving elements, 16. tuned circuits, 17. screw filters, 18. radio-frequency amplifiers, 19. difference frequency sample circuits, 20. low-frequency amplifiers, 21.A/D converter, 22.FPGA processing unit, 23. communications optical cables, 24. industry control host computers, 25.MCU control module II, 26. trigger controllers, protective cover before 27. radar shells, 28. radar shells, protective cover after 29. radar shells, 30. orthogonal directed receiving antennas, 31. high-performance emitting antennas, 32. electromagnetic wave transmittings, receive and treatment circuit, 33. screw threads, 34. communications optical cables, 35. foamed materials.

Embodiment

Below in conjunction with accompanying drawing and embodiment, the utility model is described in further detail.

The directed geological radar of a kind of single hole of surveying for tunnel geological, as shown in Figure 5, comprise radar antenna shell 1, high-performance emitting antenna 31, orthogonal directed receiving antenna 30 and electromagnetic wave transmitting, receive and treatment circuit 32, the rear and front end of described radar antenna shell 1 is respectively by installing protective cover 27 before radar shell additional by screw thread 33, protective cover 29 after radar shell, to be easy for installation and removal, described radar shell cylinder 28 outsides install one deck additional and have the soft foam material 35 of buffer action, can play glass fibre reinforced plastics casing wearing and tearing and the effect of being damaged by pressure by foreign matter of preventing, the high-performance emitting antenna 31 of emitting electromagnetic wave is equipped with in described radar antenna shell 1 inside, orthogonal directed receiving antenna 30 and electromagnetic wave transmitting, receive and treatment circuit 32, described orthogonal directed receiving antenna 30 is sent the electromagnetic wave receiving into electromagnetic wave receiving circuit, again described electromagnetic wave is sent into electromagnetic wave treatment circuit, described orthogonal directed receiving antenna 30 bodies adopt dividing plate 2 to be divided into 4 parts, a receiving antenna unit 5 is set in every part, form dephased four receiving elements independently of tool, and communicate by communications optical cable 34 and industry control host computer 24.

Described radar shell 28 is fiberglass cylinder.

After protective cover 27 and radar shell, protective cover 29 is streamlined before described radar shell, and the effect that can play waterproof and stop foreign matter to enter radar inside, protects radar pack to greatest extent and reduce radar jammed possibility in boring.

Described high-performance emitting antenna 31 adopts dipole emitting antenna.

Described orthogonal directed receiving antenna, as depicted in figs. 1 and 2, comprise the antenna casing 1 that adopts fiber reinforced plastic barrel, the receiving antenna unit 5 of four alumina based materials that are divided into through dividing plate 2 and the concentric cable 6 that transmits and receive signal for transmitting radar wave that is positioned at dividing plate 2 intersections, the outer antenna element shell 4 that adopts ambroin that is provided with in the receiving antenna unit loading with resistance 5 of described employing dipole antenna, to increase frequency span, antenna transmission frequency is 200～300MHz, described dividing plate 2 adopts ambroin, receive the electromagnetic wave phase differences information after geologic body response by 4 stand-alone antenna receiving elements, can draw the azimuth information of geologic anomaly body.

In described dipole antenna, every antenna length is 1/4 wavelength, and centre is the filled media 3 of high-k, TiO ₂powder, its relative dielectric constant is 110, to increase the equivalent length between antenna element, reduce antenna size, the orthogonal placement of two electrode couple sub antennas, four antenna elements 5 are carried out to suitable feed, can, by four antenna elements 5 comprehensive one-tenth one tours antenna on the vertical plane of boring, therefore on the vertical plane of boring, there is directivity.On the length direction of boring, antenna element 5 length are elected the half-wavelength of corresponding centre frequency as, and therefore receiving antenna also has directivity in the plane that comprises boring.For directional antenna, owing to will recording little phase differential, time or frequency accuracy just seem and are even more important, and are mainly orientation and broadband to the requirement of antenna.For example described antenna element shell 4 adopts ambroin, and described antenna element 5 adopts alumina based material, and described antenna element 5 use resistance load, and to increase frequency span, antenna transmission frequency is 200～300MHz.Receive the electromagnetic wave phase differences information after geologic body response by 4 stand-alone antenna receiving elements, can draw the azimuth information of geologic anomaly body.

Described radar electromagnetic wave radiating circuit comprises MCU control module I13, sine-wave generator 7, amplifier 8, frequency sampling circuit 12, modulation circuit 9, synchronization control circuit 11, power amplifier 10 and emitting antenna 14, adopt MCU control module I13 to control sine-wave generator 7 and produce the transformable sine wave signal of wide-band, by amplifier 8, described sine wave signal is amplified, and feed back to MCU control module I13 adjustment sine wave signal frequency by frequency sampling circuit 12, realize occurrence frequency accurately controlled; MCU control module I13 produces pulse width signal modulation by synchro control modulation circuit 11 simultaneously, and carrier modulation is become to pulse signal and is input to emitting antenna 14 through two stage power amplifier 10, realizes electromagnetic transmitting.

Described radar electromagnetic wave receives and treatment circuit, as shown in Figure 4, comprise independently receiving element 15 of 4 tunnels, 1 MCU control module II25 and 1 FPGA processing unit 22, the signal of reflection of electromagnetic wave is through independently receiving element 15 of 4 tunnels, tuning through 4 tunnels again, filtering, sampling and amplifying circuit receive the echo of corresponding transmission frequency, MCU control module II25 is according to the parameter of the frequency adjustment tuned circuit 16 of emitting electromagnetic wave, screw filter 17 carries out filtering to high frequency reflected signal, filtering interfering noise, carry out signal amplification by radio-frequency amplifier 18 again, then signal is sent into difference frequency sample circuit 19, difference frequency sample circuit 19 is controlled to high-frequency signal and MCU the 220Hz local oscillation signal that trigger controller 26 produces and is carried out mixing output intermediate-freuqncy signal, intermediate-freuqncy signal amplifies to improve machine sensitivity through low-frequency amplifier 20, entering afterwards A/D converter 21 changes again, transformation result is sent into MCU control module II25 and is processed, MCU carries out FEEDBACK CONTROL to trigger controller 26 simultaneously.

Described FPGA processing unit 22 adopts the design proposal of the synchronous A/D converter 21 of high speed processor and 4 tunnels based on FPGA, and use digital circuit synchronous logic technology and data fifo buffer technology, described A/D converter 21 adopts the acquisition module that is more than or equal to 12bit1GHz, to improve the time resolution of radar, the huge data volume that described FPGA processor selects high speed FPGA outer expansion capacity SRAM to produce to process A/D converter 21, data after FPGA processing unit 22 is sampled to A/D converter 21 store and pre-service, and by communications optical cable 23 by pretreated digital data transmission to industry control host computer 24, save the time of data transmission to main frame, therefore can use higher data sampling rate, thereby improve the measuring accuracy of the phase differential of 4 independent antenna elements, and then the precision of guarantee geologic anomaly body angle orientation.

Because being equivalent to, the position angle of plastid poorly finds the poorly incident angle of plastid reflection wave, there is lower signal to noise ratio (S/N ratio) from the signal of directional antenna, calculate the poorly incident angle of plastid reflection wave by Optimum Theory, its objective function is as follows, thereby can realize the accurate location of plastid poorly:

$\mathrm{\Φ}\left({\mathrm{\α}}_i\right)=\underset{i=i_1}{\overset{i_2}{\mathrm{\Σ}}}{(v_i\cos {\mathrm{\α}}_i+h_i\sin {\mathrm{\α}}_i)}^2$

Wherein Φ is ceiling capacity, the incident angle that α is reflection wave, and v is the signal on boring vertical plane, and h is the signal on boring length direction, and i is i sub-sampling.

The detection method that utilizes above-mentioned radar, is characterized in that, adopts by four orthogonal directed receiving antennas 30 that independently receiving element combines, and is optimized to calculate extracts azimuth information by information such as the phase differential between four; Receive and treatment circuit at the inner integrated radar signal of antenna, signal, reduce signal transmission delay, improve the time precision of system.

By reference to the accompanying drawings embodiment of the present utility model is described although above-mentioned; but the not restriction to the utility model protection domain; one of ordinary skill in the art should be understood that; on the basis of the technical solution of the utility model, those skilled in the art do not need to pay various amendments that creative work can make or distortion still in protection domain of the present utility model.

Claims (9)

1. the directed geological radar of the single hole of surveying for tunnel geological, it is characterized in that, comprise radar antenna shell, high-performance emitting antenna, orthogonal directed receiving antenna and electromagnetic wave transmitting, receive and treatment circuit, before the rear and front end of described radar antenna shell installs additional by fixing or manner respectively, rear protective cover, described radar antenna enclosure is equipped with the high-performance emitting antenna of emitting electromagnetic wave, orthogonal directed receiving antenna and electromagnetic wave transmitting, receive and treatment circuit, described orthogonal directed receiving antenna is sent the electromagnetic wave receiving into electromagnetic wave receiving circuit, again described electromagnetic wave is sent into electromagnetic wave treatment circuit, described orthogonal directed receiving antenna body adopts dividing plate to be divided into 4 parts, a receiving antenna unit is set in every part, form dephased four receiving elements independently of tool.

2. the directed geological radar of a kind of single hole of surveying for tunnel geological as claimed in claim 1, is characterized in that, described radar shell is fiberglass cylinder.

3. the directed geological radar of a kind of single hole of surveying for tunnel geological as claimed in claim 1, is characterized in that, described forward and backward protective cover is streamlined.

4. the directed geological radar of a kind of single hole of surveying for tunnel geological as claimed in claim 1, is characterized in that, described high-performance emitting antenna adopts dipole emitting antenna.

5. the directed geological radar of a kind of single hole of surveying for tunnel geological as claimed in claim 1, it is characterized in that, described orthogonal directed receiving antenna comprises the receiving antenna unit of four alumina based materials that adopt the antenna casing of fiber reinforced plastic barrel, are divided into through dividing plate and is positioned at the concentric cable that transmits and receive signal for transmitting radar wave of dividing plate intersection, outside the receiving antenna unit loading with resistance of described employing dipole antenna, be provided with the antenna element shell that adopts ambroin, described dividing plate adopts ambroin.

6. the directed geological radar of a kind of single hole of surveying for tunnel geological as claimed in claim 5, is characterized in that, in described dipole antenna, every antenna length is 1/4 wavelength, and centre is the filled media of high-k, the orthogonal placement of two electrode couple sub antennas.

7. the directed geological radar of a kind of single hole of surveying for tunnel geological as claimed in claim 1, it is characterized in that, described radar electromagnetic wave radiating circuit comprises MCU control module I, sine-wave generator, amplifier, frequency sampling circuit, modulation circuit, synchronization control circuit, power amplifier and emitting antenna, adopt MCU control module I to control sine-wave generator and produce the transformable sine wave signal of wide-band, by amplifier, described sine wave signal is amplified, and feed back to MCU control module I adjustment sine wave signal frequency by frequency sampling circuit; MCU control module I produces pulse width signal modulation by synchro control modulation circuit simultaneously, and carrier modulation is become to pulse signal and is input to emitting antenna through two stage power amplifier.

8. the directed geological radar of a kind of single hole of surveying for tunnel geological as claimed in claim 1, it is characterized in that, described radar electromagnetic wave receives and treatment circuit comprises independently receiving element of 4 tunnels, 1 MCU control module II and 1 FPGA processing unit, the signal of reflection of electromagnetic wave is through independently receiving element of 4 tunnels, tuning through 4 tunnels again, filtering, sampling and amplifying circuit receive the echo of corresponding transmission frequency, MCU control module II regulates the parameter of tuned circuit, screw filter carries out filtering to high frequency reflected signal, carry out signal amplification by radio-frequency amplifier again, then send into difference frequency sample circuit, difference frequency sample circuit carries out mixing output intermediate-freuqncy signal to the 220Hz local oscillation signal of high-frequency signal and the generation of MCU control trigger controller, intermediate-freuqncy signal enters A/D converter conversion after low-frequency amplifier amplifies again, transformation result is sent into MCU control module II and is processed.

9. the directed geological radar of a kind of single hole of surveying for tunnel geological as claimed in claim 8, it is characterized in that, described FPGA processing unit adopts high speed processor based on FPGA and the design proposal of the 4 synchronous A/D converters in tunnel, FPGA processing unit stores and pre-service the data after A/D converter sampling, and by communications optical cable by pretreated digital data transmission to industry control host computer.