CN202230210U - Intelligent very low frequency electromagnetic instrument with orthogonal antenna - Google Patents
Intelligent very low frequency electromagnetic instrument with orthogonal antenna Download PDFInfo
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- CN202230210U CN202230210U CN2011201315551U CN201120131555U CN202230210U CN 202230210 U CN202230210 U CN 202230210U CN 2011201315551 U CN2011201315551 U CN 2011201315551U CN 201120131555 U CN201120131555 U CN 201120131555U CN 202230210 U CN202230210 U CN 202230210U
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Abstract
The utility model discloses an intelligent very low frequency electromagnetic instrument with an orthogonal antenna, which comprises an electromagnetic induction signal receiving unit, a signal processing unit, an output unit, a Global Position System (GPS) positioning unit and an electronic positioning unit, wherein the GPS positioning unit, the electronic positioning unit and the electromagnetic induction signal receiving unit are connected with the signal processing unit; the signal processing unit is connected with the output unit and transmits data to the output unit; the electromagnetic induction signal receiving unit includes an orthogonal receiving antenna and a very low frequency wave band receiving module; the orthogonal receiving antenna induce electromagnetic signals and transmits the signals to the very low frequency wave band receiving module; the very low frequency wave band receiving module outputs amplitude values of the electromagnetic signals to the signal processing unit; and the signal processing unit processes the signals and sends data to the output unit so that the output unit can output the data. The intelligent very low frequency electromagnetic instrument uses the orthogonal receiving antenna which can simultaneously acquire electromagnetic component signals in the horizontal direction and electromagnetic component signals in the vertical direction at one measurement spot, therefore determination of measurement wires and measurement spots can be accomplished automatically, and errors produced by manual operation are reduced.
Description
Technical field
The utility model relates to a kind of surveying instrument of electromagnetic induction signal, relates in particular to the digital very low frequency electromagnetical receiver of the electromagnetic induction signal difference that a kind of electromagnetic wave of measuring very low frequency (VLF) radio station emission causes, it has orthogonal antenna.
Background technology
The magnetic component that vertical electric dipole produced that is positioned at the face of land has only horizontal component, if in the far field and consider the field in the limited area, primary field approaches along the face of land to be close to the transverse magnetic field plane wave of the incident that is oriented in a tangential direction usually.Electrical discrepant geologic body in underground part or interphase will induce secondary field under the effect of horizontal primary field, then vertical component must occur; Primary field is identical with the secondary field frequency; But phase place and amplitude are inconsistent, and their interaction forms synthetic, synthetic elliptical polarization spatially (synthetic track is oval); The tangent value of its polarization ellipse inclination angle D angle of Z-axis (ellipse short shaft with) is directly proportional with the secondary field vertical component; Therefore, the variation at the oval inclination angle of measurement of polarization in fact just can reflect the variation of induction secondary field vertical component.
Very low frequency electromagnetical receiver just the electromagnetic wave (radiowave of 15-25KHz wave band) through measuring the emission of very low frequency (VLF) radio station on the face of land, aerial or electromagnetic induction signal difference that the subsurface investigation field causes; Thereby obtain the electrical property feature of measurement zone geologic body, and then judge the abnormal information of the electrically unusual or underground structure of geologic body.At present, very low frequency electromagnetical receiver has become survey instrument important in underground water detection, prospecting for mineral deposits and the geologic mapping, especially at aspects such as surveying the latent metal mineralising low-resistance band of shallow-layer, structure shatter belt and moisture fracture fissure zone very large effect is arranged.
Present domestic very low frequency (VLF) electromagnetic measurement equipment adopts the single antenna construction principle design, and this design makes that in data acquisition operating personnel need be after finding horizontal survey component peak signal; Keep the measuring position motionless; Instrument with the hands being held up, and keep instrument perpendicular to the ground, is axle then with the wrist; Rotate instrument and seek the maximal value of vertical component, write down the magnetic dip of this point then.This metering system, the one-shot measurement result need divide for two steps accomplished, and not only increased operating personnel's working strength, and for guaranteeing measuring accuracy, reduced error, require a survey line as far as possible a people operate completion.This equipment needs in surveying the district, to reserve survey line and measuring point according to measurement requirement by survey crew earlier in measuring process in addition; And in the measuring point marked; The very low frequency (VLF) operating personnel begin to measure according to measurement markers more then; This mode is not only lost time and human resources, and the opposing party is easy error in close-in measurement.Simultaneously, measurement result is projected to the gps measurement data that also often need add on the map.
Summary of the invention
The purpose of the utility model is to overcome existing very low frequency electromagnetical receiver single antenna operation and needs proceed step by step and location defect automatically; A kind of New Digital very low frequency electromagnetical receiver is provided; Can one-shot measurement electromagnetic induction signal horizontal component and vertical component, also measure direction and position simultaneously automatically.
Digital very low frequency electromagnetical receiver with orthogonal antenna comprises electromagnetic induction signal receiving element, signal processing unit, output unit, GPS directed element and electronics directed element; GPS directed element, electronics directed element and electromagnetic induction signal receiving element are connected signal processing unit; Respectively gps signal, direction signal and electromagnetic induction signal are transferred to signal processing unit, signal processing unit connects output unit and transmits data gives output unit; The electromagnetic induction signal receiving element comprises quadrature receiving antenna and very low frequency (VLF) wave band receiver module; Quadrature receiving antenna inductive electromagnetic signal also is transferred to very low frequency (VLF) wave band receiver module with signal; The amplitude of very low frequency (VLF) wave band receiver module output electromagnetic signal is given signal processing unit, and the signal processing unit processes signal also sends data to output unit output.
Said electromagnetic induction signal receiving element also comprises the phase-locked loop circuit that is used for stable electrical magnetic signal frequency, and phase-locked loop circuit is connected with very low frequency (VLF) wave band receiver module.
Said electromagnetic induction signal receiving element also comprises the measurement of dip angle module that is used to measure magnetic dip, and measurement of dip angle module transmission measurement data are given signal processing unit.
Said very low frequency (VLF) wave band receiver module comprises a wave filter, a frequency mixer, DDS frequency generating module, AGC automatic gain control circuit, IF amplifier circuit, detecting circuit and filtering circuit; The input end that is used for the electromagnetic induction signal filter filtering is connected with the output terminal of receiving antenna, and output terminal connects frequency mixer; DDS frequency generating module output terminal is connected with frequency mixer; The electromagnetic induction signal of wave filter input is connected the IF amplifier circuit that is used for the intermediate-freuqncy signal amplification with the output terminal that the signal that DDS frequency generating module produces is formed the frequency mixer of harmonic ringing; IF amplifier circuit is connected with filtering circuit with detecting circuit successively, the amplitude of filtering circuit output electromagnetic induction signal; The input end of AGC automatic gain control circuit is connected with the output terminal of detecting circuit, and output terminal is connected with IF amplifier circuit.The electromagnetic induction signal that receiving antenna receives is after filters in the input mixer; Form harmonic ringing with the electromagnetic signal that DDS frequency generating module produces; Be input to IF amplifier circuit and carry out the intermediate-freuqncy signal amplification; The intermediate-freuqncy signal of amplifying converts the amplitude output of institute's selected frequency electromagnetic induction signal into behind detecting circuit and filtering circuit, AGC automatic gain control circuit input termination IF amplifier circuit, the input end of output termination filtering circuit.Receiving antenna end band filter plays and eliminates antenna noise jamming and preliminary election long wave frequency.And frequency mixer with filtering after the signal that produces of signal and DDS frequency generating module form resonance signal, to select the radio signals of different frequency.Harmonic ringing is not enough to the amplification of small-signal through AGC automatic gain control circuit solution fixed intermediate frequency signal amplification factor then; Supersaturation problem of dtmf distortion DTMF to large-signal; Reach and guarantee that intermediate-freuqncy signal does not change with radio signals is strong and weak, impels the signal effect of tending towards stability.Last signal is through the amplitude of detecting circuit and filtering circuit output electromagnetic induction signal.
Said quadrature receiving antenna comprises the magnetic rod antenna of two orthogonal intersections.
Said magnetic rod antenna is for receiving the magnetic rod antenna of 15-25KHz wave band.
Said signal processing unit comprises main control module that is used for data processing and control and the internal storage that is used for data storage, and internal storage is connected with the main control module.
Said signal processing unit also comprises the outside extended memory interface unit that is used to connect external memory storage, and outside extended memory interface unit is connected with the main control module.
Said output unit comprises display module and host communication interface, and display module is connected with the main control module respectively with the host communication interface.The display module video data, the host communication interface is realized and upper machine communication.
Said GPS directed element is the D-GPS global positioning receiver.
The electronics directed element is the electronics bearing compass.
The beneficial effect of the utility model:
1, adopts the quadrature receiving antenna on a measurement point, to obtain level and vertical direction electromagnetic signal simultaneously, reduced the error that manual operation produces, also reduced the working strength of survey crew.
2, adopt the GPS directed element to obtain the locating information of measuring point, the electronics bearing compass obtains the direction of survey line, and both accomplish confirming of side line and measuring point jointly, have reduced personal error.
3, adopt receiving antenna and very low frequency (VLF) wave band receiver module; Detected electromagnetic induction signal noise jamming is little; Can directly show, read and store data through signal processing unit and output unit, reduce the mistake that manual record brings, also reduce personnel's work.
4, each unit in the very low frequency (VLF) wave band receiver module makes detection signal reliable and stable, disturbs for a short time, and it is accurate to detect data.
Description of drawings
Fig. 1 is the illustrative view of functional configuration of the utility model;
Fig. 2 is the structural representation of the very low frequency electromagnetical receiver of the utility model embodiment;
Fig. 3 is the structural representation of very low frequency (VLF) wave band receiver module among Fig. 2;
Fig. 4 is a receiving antenna structural representation among the utility model embodiment.
Embodiment
Be described in detail below in conjunction with the digital very low frequency electromagnetical receiver of accompanying drawing the utility model.
Digital automatic location very low frequency electromagnetical receiver with orthogonal antenna generally comprises electromagnetic induction signal receiving element 10, GPS directed element 40, electronics directed element 50, signal processing unit 20 and output unit 30, and electromagnetic induction signal receiving element 10, signal processing unit 20 and output unit 30 are connected successively.GPS directed element, electronics directed element and electromagnetic induction signal receiving element are connected signal processing unit, respectively gps signal, direction signal and electromagnetic induction signal are transferred to signal processing unit, and be as shown in Figure 1.GPS directed element 40 is D-GPS global positioning receivers.Electronics directed element 50 is the electronics bearing compass
And electromagnetic induction signal receiving element 10 comprises quadrature receiving antenna 1 and two very low frequency (VLF) wave band receiver modules 2; Quadrature receiving antenna 1 is transferred to two very low frequency (VLF) wave band receiver modules 2 respectively with vertical electrical magnetic component signal and horizontal electromagnetic component signal, and the amplitude of very low frequency (VLF) wave band receiver module 2 output electromagnetic induction signals is given signal processing unit 20.As shown in Figure 2.
The electromagnetic induction signal unit also comprises phase-locked loop circuit 3 and measurement of dip angle module 4, and phase-locked loop circuit 3 is used for stablizing the frequency of very low frequency (VLF) wave band receiver module 2 from the electromagnetic induction signal of receiving antenna acquisition, is connected with very low frequency (VLF) wave band receiver module 2.Phase-locked loop circuit 3 is connected with main control module 201 simultaneously, accepts the control of main control module 201.Measurement of dip angle module 4 is connected 201 with the main control module, measures the magnetic dip data and measurement data is transferred to the main control module 201 of signal processing unit 20.
Referring to Fig. 3; Very low frequency (VLF) wave band receiver module 2 comprises a wave filter, a frequency mixer, DDS frequency generating module, AGC automatic gain control circuit, IF amplifier circuit, detecting circuit and filtering circuit; The electromagnetic induction signal that receiving antenna receives passes through in the input circuit input mixer after filters; Electromagnetic signal with DDS frequency generating module produces is formed harmonic ringing; Be input to IF amplifier circuit and carry out intermediate-freuqncy signal and amplify, the intermediate-freuqncy signal of amplification is through the detecting circuit detection, after output institute selected frequency electromagnetic induction signal amplitude after filtering circuit filtering again.And AGC automatic gain control circuit input termination detecting circuit output terminal, output termination IF amplifier circuit.The AGC automatic gain control circuit guarantees that intermediate-freuqncy signal does not change with radio signals is strong and weak, impels signal to tend towards stability.
Referring to Fig. 2; Signal processing unit 20 comprises main control module 201, internal storage 202, outside extended memory interface unit 203; Internal storage 202 is connected with main control module 201 respectively with outside extended memory interface unit, and main control module 201 is carried out data processing and control; Internal storage 202 storage data; Outside extension storage interface 203 connects external memory storage.Be used for the growth data storage.Signal processing unit 20 can also comprise a keyboard components 204, and keyboard components 204 is responsible for the input of man-machine interaction control signal.As shown in Figure 2.Main control module 201 can be a single-chip microcomputer.
Digital very low frequency electromagnetical receiver also comprises Power Supply Assembly, is the said units power supply.
Referring to Fig. 2 and Fig. 4, the quadrature receiving antenna 1 that present embodiment adopts is the magnetic rod antenna 11 of two orthogonal intersections, and this magnetic rod antenna is the magnetic rod antenna that receives the 15-25KHz wave band.This magnetic rod antenna 11 can be straight rod, also can be the annular rod.
What the principle of work of digital very low frequency electromagnetical receiver adopted is a kind of alternating current magnetic method that works in the 15-25KHz wave band.Experiment shows, (under the f＜105Hz), the electric conductivity of rock and ore mainly shows as conduction current, and the electric conductivity of rock and ore depends primarily on their conductivity at low frequency.And the resistivity characteristic of rock and ore shows, different rocks have different electrical conductivity, and this explanation is more obvious when the electrical property difference of study area geologic body to be detected and its country rock, and then the off-note of geophysical measurement also more obviously.In addition; Grow the location at the structure shatter belt; The physico-chemical property obvious difference of structure shatter belt and its both sides country rock (weak shifting ground plastid); Especially in the structure shatter belt, grown by the filling of polymetallic ore arteries and veins, mineralized alteration zone, and the relative growth and the enrichment of fault gouge, clay mineral and underground water, crevice water, in the very low frequency (VLF) electromagnetic measurement, all there is tangible low-resistance to reflect unusually usually.The very low frequency (VLF) electromagnetic measurement just is being based on the geologic body space, and to form the distribution of conductivity of (mineral, rock) inhomogeneous, is that the oval inclination angle of its measurement of polarization changes thereby cause the measured value of very low frequency (VLF) surveying instrument, comes the electrical property feature of reflection land burial body indirectly.High-precision GPS measuring technique and very low frequency (VLF) measuring technique combined together not only can increase work efficiency greatly, and can promote the very low frequency (VLF) broad application greatly.
Method of application:
Measure to prepare: in the measurement point start, the machine self check is also searched for the very low frequency (VLF) electromagnetic signal, treat signal stabilization after, locking frequency or survey frequency manually is set.Get into the GPS pattern, confirm to measure starting point,, set up survey line grid (can in advance in indoor completion) then according to measuring design
Measure: hand-held instrument also makes the instrument level, and body erect is that axle horizontal rotates instrument then with the health, and when hearing the instrument buzzing, horizontal survey finishes; Switch to guided mode, move ahead by display screen prompting direction, hear that measuring point arrives prompting, stop, switching to measurement pattern and begin next measuring point measurement, so circulation is accomplished up to this survey line, then measures next side line.Can from display module 301, check measurement result at any time in the measuring process.
Measure to finish, through host communication interface 302 with data transmission to host computer, also can data be saved on the external memory storage through outside extension storage interface 203.Host communication interface 302 can be the RS232 interface; Outside extension storage interface 203 can be the usb interface.
Claims (10)
1. intelligent very low frequency electromagnetical receiver with orthogonal antenna; It is characterized in that comprising electromagnetic induction signal receiving element, signal processing unit, output unit, GPS directed element and electronics directed element; GPS directed element, electronics directed element and electromagnetic induction signal receiving element are connected signal processing unit; Respectively gps signal, direction signal and electromagnetic induction signal are transferred to signal processing unit, signal processing unit connects output unit and transmits data gives output unit; The electromagnetic induction signal receiving element comprises quadrature receiving antenna and very low frequency (VLF) wave band receiver module; Quadrature receiving antenna inductive electromagnetic signal also is transferred to very low frequency (VLF) wave band receiver module with signal; The amplitude of very low frequency (VLF) wave band receiver module output electromagnetic signal is given signal processing unit, and the signal processing unit processes signal also sends data to output unit output.
2. the intelligent very low frequency electromagnetical receiver with orthogonal antenna as claimed in claim 1; It is characterized in that; Said electromagnetic induction signal receiving element also comprises the phase-locked loop circuit that is used for stable electrical magnetic signal frequency, and phase-locked loop circuit is connected with very low frequency (VLF) wave band receiver module.
3. the intelligent very low frequency electromagnetical receiver with orthogonal antenna as claimed in claim 1 is characterized in that said electromagnetic induction signal receiving element also comprises the measurement of dip angle module that is used to measure magnetic dip.
4. the intelligent very low frequency electromagnetical receiver with orthogonal antenna as claimed in claim 1; It is characterized in that; Said very low frequency (VLF) wave band receiver module comprises a wave filter, a frequency mixer, DDS frequency generating module, AGC automatic gain control circuit, IF amplifier circuit, detecting circuit and filtering circuit; The input end that is used for the electromagnetic induction signal filter filtering is connected with the output terminal of receiving antenna, and output terminal connects frequency mixer; DDS frequency generating module output terminal is connected with frequency mixer; The electromagnetic induction signal of wave filter input is connected the IF amplifier circuit that is used for the intermediate-freuqncy signal amplification with the output terminal that the signal that DDS frequency generating module produces is formed the frequency mixer of harmonic ringing; IF amplifier circuit is connected with filtering circuit with detecting circuit successively, the amplitude of filtering circuit output electromagnetic induction signal; The input end of AGC automatic gain control circuit is connected with the output terminal of detecting circuit, and output terminal is connected with IF amplifier circuit.
5. the intelligent very low frequency electromagnetical receiver with orthogonal antenna as claimed in claim 1 is characterized in that said quadrature receiving antenna comprises the magnetic rod antenna of two orthogonal intersections.
6. the intelligent very low frequency electromagnetical receiver with orthogonal antenna as claimed in claim 5 is characterized in that, said magnetic rod antenna is for receiving the magnetic rod antenna of 15-25KHz wave band.
7. the intelligent very low frequency electromagnetical receiver with orthogonal antenna according to claim 1; It is characterized in that; Said signal processing unit comprises main control module that is used for data processing and control and the internal storage that is used for data storage, and internal storage is connected with the main control module.
8. the intelligent very low frequency electromagnetical receiver with orthogonal antenna according to claim 1 is characterized in that said output unit comprises display module and host communication interface, and display module is connected with the main control module respectively with the host communication interface.
9. the intelligent very low frequency electromagnetical receiver with orthogonal antenna according to claim 1 is characterized in that said GPS directed element is the D-GPS global positioning receiver.
10. the intelligent very low frequency electromagnetical receiver with orthogonal antenna according to claim 1 is characterized in that said electronics directed element is the electronics bearing compass.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011201315551U CN202230210U (en) | 2011-04-29 | 2011-04-29 | Intelligent very low frequency electromagnetic instrument with orthogonal antenna |
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| Application Number | Priority Date | Filing Date | Title |
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| CN2011201315551U CN202230210U (en) | 2011-04-29 | 2011-04-29 | Intelligent very low frequency electromagnetic instrument with orthogonal antenna |
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| CN202230210U true CN202230210U (en) | 2012-05-23 |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105353418A (en) * | 2015-12-04 | 2016-02-24 | 唐山迁西坤宇物探科技有限公司 | Ion remote sensing geophysical prospecting instrument and remote sensing geophysical prospecting method thereof |
| CN107271539A (en) * | 2017-07-03 | 2017-10-20 | 中国船舶重工集团公司第七六研究所 | A kind of sea-bottom oil-gas pipeline leakage field/very low frequency receives detection localization method and device |
| CN108983297A (en) * | 2018-06-15 | 2018-12-11 | 中国科学院地质与地球物理研究所 | A kind of surface em signal deteching circuit |
-
2011
- 2011-04-29 CN CN2011201315551U patent/CN202230210U/en not_active Expired - Fee Related
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105353418A (en) * | 2015-12-04 | 2016-02-24 | 唐山迁西坤宇物探科技有限公司 | Ion remote sensing geophysical prospecting instrument and remote sensing geophysical prospecting method thereof |
| CN107271539A (en) * | 2017-07-03 | 2017-10-20 | 中国船舶重工集团公司第七六研究所 | A kind of sea-bottom oil-gas pipeline leakage field/very low frequency receives detection localization method and device |
| CN108983297A (en) * | 2018-06-15 | 2018-12-11 | 中国科学院地质与地球物理研究所 | A kind of surface em signal deteching circuit |
| CN108983297B (en) * | 2018-06-15 | 2019-07-16 | 中国科学院地质与地球物理研究所 | A kind of surface em signal deteching circuit |
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Granted publication date: 20120523 Termination date: 20140429 |