CN206193264U - Flux -gate magnetometer's signal detection circuit and this flux -gate magnetometer - Google Patents
Flux -gate magnetometer's signal detection circuit and this flux -gate magnetometer Download PDFInfo
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- CN206193264U CN206193264U CN201621270096.4U CN201621270096U CN206193264U CN 206193264 U CN206193264 U CN 206193264U CN 201621270096 U CN201621270096 U CN 201621270096U CN 206193264 U CN206193264 U CN 206193264U
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Abstract
The utility model relates to an earthquake technical field discloses a flux -gate magnetometer's signal detection circuit and this flux -gate magnetometer. Signal detection circuit include from the sensing probe acquire the magnetic field signal signalling channel and to sensing probe output drive signal's excitation passageway, and signalling channel is including the probe input circuit, frequency -selecting amplifier circuit, phase sensitivity detection circuit, integrating circuit and the feedback circuit that connect gradually, wherein feedback circuit includes: the the first feedback route is configured as linear feedback circuit, and the second feedback path, it is parallelly connected with the the first feedback route, be configured as the nonlinear feedback circuit, and the magnetic field signal that detects at the sensing probe of this second feedback path is worked when reaching the biggest measuring range of relative observation. The utility model discloses a non -linear negative feedback method, change different feedback branch at little signal input during with big signal input, solved the problem that traditional signal detection circuit can not compromise the resolution ratio of guaranteeing the signal and permit big signal input.
Description
Technical field
The utility model is related to seismic technology field, the signal deteching circuit of more particularly to a kind of flux-gate magnetometer and
The flux-gate magnetometer.
Background technology
Geomagnetic signal carries the geophysical information of non-lipid, therefore geomagnetic observation is that Earthquake In China Precursor Network is important
Observation method, and flux-gate magnetometer is wherein mostly important observation instrument.Flux-gate magnetometer is that one kind is used to measure
The vector mode fast-response probe of D.C. magnetic field or low frequency magnetic field, using most when it is measurement quasistatic and slow change vector magnetic field
It is extensive instrument, is also vector mode magnetic field sensor most accurate at room temperature, is capable of intensity and the side in accurate measurement earth's magnetic field
To, there is good low noise, high resolution, temperature stability, Wide measuring range, weak magnetic survey, low-power consumption and high accuracy,
So as to turn into magnetic survey instrument the most frequently used at room temperature, it is widely used in from accurate geophysics to safety and medical domain, this
It is outer to be also usually applied to the fields such as archaeology, subsurface investigation and military surveillance.
As shown in figure 1, the signal deteching circuit of current flux-gate magnetometer is main by with the output signal of sensing probe 1
Vi(output signal ViThe magnetic field signal that i.e. sensing probe is detected) exported as the signalling channel of input signal and to sensing probe 1
Pumping signal VdExcitation passage two parts composition, signalling channel mainly include probe input circuit 2, selective frequency amplifier circuit 3, phase sensitivity
Detecting circuit 4, integrating circuit 5, the several parts of feedback circuit 6, output signal V is obtained after its integrated circuito, output signal Vo
Processed through feedback circuit 6 again and generate the final feedback signal V for feeding back to sensing probe 1f；Excitation passage can then include high frequency vibrating
Circuit, frequency dividing circuit, phase-shift circuit and the several parts of power amplification are swung, its output reference signal VrTo phase-sensitive detection circuit 4.Wherein
Selective frequency amplifier circuit 3 is used to suppress significantly fundamental wave and other non-second harmonic noises, and amplifies useful sensor second harmonic
Signal, improves signal detection resolution ratio.Selective frequency amplifier circuit 3 can bring the phase place change of signal, and the linear of saturation is not up in circuit
In the range of, this phase change is fixed, can be compensated by configuring phase-shift circuit in signal deteching circuit.But,
As the input signal V of signalling channeliIt is excessive and make signal deteching circuit enter saturation when, generate new additional phase shift, make rear end pair
The detection efficiency reduction of the phase-sensitive detection circuit 4 of phase sensitive, or even output polarity reversion, so that whole signal deteching circuit becomes
It is unstable.Therefore, there is the resolution ratio and appearance that can not take into account signal to signal in the signal deteching circuit of existing flux-gate magnetometer
The problem of perhaps big signal input, is difficult to further improve its resolution ratio for the Geomagnetic signal with " weak signal, strong background " feature.
Utility model content
The purpose of this utility model is to provide the signal deteching circuit and the flux-gate magnetometer of a kind of flux-gate magnetometer,
Signal deteching circuit for solving existing flux-gate magnetometer can not be taken into account and ensure the resolution ratio of signal and allow big signal
The problem of input.
To achieve these goals, the utility model provides a kind of signal deteching circuit of flux-gate magnetometer, the signal
Detection circuit includes obtaining the signalling channel of magnetic field signal and swashing to the sensing probe output drive signal from sensing probe
Passage is encouraged, the signalling channel includes the probe input circuit, selective frequency amplifier circuit, phase-sensitive detection circuit, the integration that are sequentially connected
Circuit and feedback circuit, wherein, the feedback circuit includes：First feedback network, is configured as linear feedback circuit；And the
Two feedback networks, it is in parallel with first feedback network, non-linear feedback circuit, and second feedback network are configured as in institute
The magnetic field signal for stating sensing probe detection works when reaching the maximum measurement range of relative observation.
Alternatively, the feedback circuit also includes：Adder, its described first feedback network of connection and the second feedback network
Signal output part, the output signal of first feedback network and the second feedback network is exported for phase adduction.
Alternatively, first feedback network includes first resistor.
Alternatively, second feedback network includes：Breakover element, its described integrating circuit of connection, and be configured as
The magnetic field signal of the sensing probe detection is turned on when reaching the maximum measurement range of relative observation；Amplifier, its input connects
The breakover element is connect, for when the breakover element is turned on, amplifying the output signal of the breakover element；And second electricity
Resistance, the output end of its connection amplifier.
Alternatively, the conducting voltage of the breakover element is equal to the magnetic field that the integrating circuit is detected in the sensing probe
Signal reaches maximum available output power during the maximum measurement range of relative observation.
Alternatively, the signalling channel also includes the amplitude limiter circuit being connected with the integrating circuit, for making the integration
The output voltage of circuit is limited in the maximum that the integrating circuit reaches relative observation in the magnetic field signal that the sensing probe is detected
In the range of maximum available output power during measurement range.
Alternatively, the breakover element uses voltage-stabiliser tube, piezo-resistance or voltage comparator.
Alternatively, the voltage-stabiliser tube uses bi-directional voltage stabilizing pipe, and its one end connects the output end of the integrating circuit, the other end
The positive input terminal of the amplifier is connected, the positive input terminal and negative input end of the amplifier are respectively grounded respectively by resistance, and
Resistance is connected between the negative input end of the amplifier and its output end.
The utility model additionally provides a kind of flux-gate magnetometer, and the flux-gate magnetometer is provided with above-mentioned signal inspection
Slowdown monitoring circuit.
By above-mentioned technical proposal, the beneficial effects of the utility model are：The utility model make use of non-linear negative-feedback
Method, different feedback branches are converted in small-signal input (in linear measurement range) and during big signal input, solve biography
System signal deteching circuit there is a problem of that the resolution ratio of guarantee signal can not be taken into account and allow big signal input.
Other features and advantages of the utility model will be described in detail in subsequent specific embodiment part.
Brief description of the drawings
Accompanying drawing is further understood to of the present utility model for providing, and constitutes a part for specification, and following
Specific embodiment be used to explain the utility model together, but do not constitute to limitation of the present utility model.In the accompanying drawings：
Fig. 1 is the structural representation of the signal deteching circuit of flux-gate magnetometer in the prior art；
Fig. 2 is the input/output signal relation schematic diagram of the signal deteching circuit of flux-gate magnetometer in the prior art；
Fig. 3 is the structural representation of the signal deteching circuit of the flux-gate magnetometer of the utility model embodiment；
Fig. 4 is the input/output characteristic schematic diagram of the signal deteching circuit of the utility model embodiment；
Fig. 5 is a kind of schematic diagram of preferred structure of the feedback circuit of the utility model embodiment；
Fig. 6 is the particular circuit configurations schematic diagram of the feedback circuit of pie graph 5 in the utility model embodiment.
Description of reference numerals
The probe input circuit of 1 sensing probe 2
The phase-sensitive detection circuit of 3 selective frequency amplifier circuit 4
The feedback circuit of 5 integrating circuit 6
The feedback network of 61 first feedback network 62 second
The first resistor of 63 adder 611
The amplifier of 621 breakover element 622
623 second resistances
Specific embodiment
Specific embodiment of the present utility model is described in detail below in conjunction with accompanying drawing.It should be appreciated that herein
Described specific embodiment is merely to illustrate and explains the utility model, is not limited to the utility model.
With reference to Fig. 1, the feedback circuit 6 of the existing signal deteching circuit of flux-gate magnetometer is by single resistance RfConstitute,
It is linear feedback circuit that it substantially belongs to.
The input/output signal relation of integrating circuit is as shown in Fig. 2 abscissa is defeated in figure in existing signal deteching circuit
Enter, unit is nT, ordinate is output, unit is that solid line is preferable normal output in V, and figure, and corresponding dotted line is actual
Unstable output.With reference to Fig. 1 and Fig. 2, when the input signal (magnetic field signal for detecting) of sensing probe 1 is relative beyond earth magnetism
During linear measurement range (such as ± 2500nT) of observation, the output of integrating circuit 5 reaches saturation, and feedback circuit 6 exported and also reach most
Greatly.When external magnetic field enhancing makes the input signal of sensing probe 1 further increase, due to feedback signal VfCan not again with input
Increase and continue to increase, the links such as selective frequency amplifier circuit 3 is entered saturation state, so as to generate new additional phase shift,
So that reference signal V of the signal of these links output with phase-sensitive detection circuit 4rPhase it is no longer identical, then generate with
The size of input signal and the phase difference that changes, the phase difference can cause the reduction of detection efficiency, and by the flat of integrating circuit 5
V is exported after cunningoAlso may change, or even make polarity inversion, be i.e. output signal VoBecome unstable, be no longer able to linear anti-
Reflect the size of input magnetic field signal.Further, in practice in order to ensure the stability of signal deteching circuit, the frequency-selecting of front end
Amplifying circuit etc. pretreatment circuit link quality factor q value can not be too high, therefore, it is difficult to ensure selective frequency amplifier circuit etc. have compared with
Good filter effect, so that during small-signal, magnetometer system signal noise ratio is not high, have impact on magnetic force instrument system to faint small letter
Number resolution ratio.
On this basis, the utility model embodiment proposes a kind of new fluxgate magnetic force based on nonlinear feedback theory
The signal deteching circuit of instrument, as shown in figure 3, the signal deteching circuit also includes signalling channel and excitation passage, the signal leads to
Road includes the probe input circuit 2, selective frequency amplifier circuit 3, phase-sensitive detection circuit 4, integrating circuit 5 and the feedback circuit that are sequentially connected
6, wherein phase-sensitive detection circuit 4 is preferably phase-sensitive detector PSD, and integrating circuit 5 is preferably regular integral device.And encourage passage
Construction is similar to existing flux-gate magnetometer, and concrete function and structure refer to pertinent literature, and it is not belonging to the utility model
Embodiment wants improved plan content, therefore seldom states herein.
Relative to existing flux-gate magnetometer, the feedback circuit of the signal deteching circuit involved by the utility model embodiment
6 include：First feedback network 61, it is configured as linear feedback circuit；And second feedback network 62, with the described first feedback
Path 61 is in parallel, is configured as non-linear feedback circuit, the magnetic field letter that second feedback network 62 is detected in the sensing probe 1
Worked during the maximum measurement range for number reaching relative observation.
Further, feedback circuit 6 also includes described in the present embodiment：Adder 63, its described first feedback network of connection
61 and second feedback network 62 signal output part, export the feedback network of the first feedback network 61 and second for phase adduction
62 output signal.
Fig. 4 is the output characteristics schematic diagram of the feedback circuit of the utility model embodiment.In the input of the signalling channel
Signal ViWhen being the small-signal input in linear measurement range, as shown in figure 4, as in ± 2500nT linear measurement ranges
When small-signal is input into, only the first feedback network 61 is worked and output feedback signal, and the second feedback network 62 is exported in high resistant
State, does not contribute feedback signal.When input exceedes the linear measurement range of ± 2500nT, the second feedback network 62 enters
Working condition, feedback signal is exported by the first feedback network 61 and constituted plus the output of the second feedback network 62, and the second feedback is logical
The output of road 62 is exported much larger than the first feedback network 61, i.e., now feedback signal is mainly made up of the second feedback network 62, now
Signal deteching circuit feedback quantity is big, and magnetometer system detectio sensitivity is low, selective frequency amplifier circuit of front end etc. is simulated pretreatment
Circuit will not enter saturation state, hereby it is ensured that the stability of the output such as phase-sensitive detection circuit.Additionally, the feedback of adjustment second is logical
The output on road 62, can be such that the signal deteching circuit when external magnetic field reaches the largest of about 50000nT exports close to the full width of supply voltage VCC
Degree output, then voltage output is limited in the spiking output ± U of integrating circuit by amplitude limiter circuitomThe range of linearity in.
Further, as shown in figure 5, the utility model embodiment provides the feedback in the corresponding signal deteching circuits of Fig. 3
One kind of circuit preferably comprises mode, wherein first feedback network 61 can include first resistor 611, it constitutes typical
Linear feedback circuit.Second feedback network 62 can include：Breakover element 621, its described integrating circuit 5 of connection, and quilt
The magnetic field signal being configured in the detection of the sensing probe 1 is turned on when reaching the maximum measurement range of relative observation；Amplifier
622, its input connects the breakover element 621, for when the breakover element 621 is turned on, amplifying the breakover element
621 output signal；And second resistance 623, the output end of its connection amplifier 622.
Wherein, the breakover element 621 can use voltage-stabiliser tube, piezo-resistance or voltage comparator, the amplifier 622
Conventional operational amplifiers can be used with the adder 63.With the breakover element 621 using bi-directional voltage stabilizing pipe, the amplification
Device 622 and the adder 63 are implemented using as a example by conventional operational amplifiers as shown in fig. 6, giving and constituting the utility model
One particular circuit configurations of the feedback circuit of example, in the circuit structure, the first feedback circuit 61 is made up of resistance R1, its one end
Connect the output end of integrating circuit 5, the negative input end output feedback signal of the adder that the other end is constituted to operational amplifier A 1
Vf1, and resistance R6 is connected between the negative input end and output end of the operational amplifier A 1, the second feedback circuit 62 then includes：It is double
To voltage-stabiliser tube D, its one end connects the output end of integrating circuit 5, the positive input terminal of other end concatenation operation amplifier A2；Computing is put
Big device A2 constitutes the amplifier 622, and its positive input terminal is also grounded by resistance R5, and negative input end is grounded by resistance R4, is born
Resistance R3 is connected between input and output end；Resistance R2 constitutes second resistance 623, its one end concatenation operation amplifier A2's
Output end, negative input end output feedback signal V from the other end to operational amplifier A 1f2。
For the circuit shown in Fig. 6, two-way feedback signal Vf1、Vf2After the adder constituted through operational amplifier A 1 is added
As total feedback signal Vf.With reference to Fig. 4, when tested magnetic field is less than relative measurement scope (such as ± 2500nT), integration electricity
The output V on roadoLess than its maximum effectively output signal ± Uom, output voltage VoLess than the conducting voltage V of bi-directional voltage stabilizing pipe DZ(i.e.
VZ=Uom) and the second feedback network 62 is output as zero, therefore feedback signal is only provided by the first feedback network 61, and size with
Output VoIt is directly proportional.When the conducting voltage of the breakover element is equal to or more than the maximum available output power of the integrating circuit
When, when being tested magnetic field more than opposite linear measurement range, the output V of integrating circuitoMore than maximum effectively output signal ± Uom, make
Bi-directional voltage stabilizing pipe D is turned on, now feedback signal VfBy Vf1And Vf2Composition is added, makes signal deteching circuit sensitivity decrease.
The resistance ratio of the second feedback network is adjusted, can be made defeated when tested magnetic field reaches maximum measurement range (such as ± 50000nT)
Go out VoClose to power supply amplitude VCC.Furthermore it is also possible to for the signalling channel sets the amplitude limit being connected with integrating circuit electricity
Road, for making the output voltage V of the integrating circuitoIt is limited in the maximum available output power ± U of the integrating circuitomScope
It is interior.
Further, on the basis of above-mentioned signal deteching circuit, the utility model embodiment additionally provides a kind of magnetic flux
Door magnetometer, the flux-gate magnetometer is provided with above-mentioned signal deteching circuit.Composition on the signal deteching circuit can join
Text is admitted to, be will not be repeated here.
In sum, the signal deteching circuit of the flux-gate magnetometer of the utility model embodiment make use of non-linear negative anti-
Feedback method, different feedback branches are converted in small-signal input (in linear measurement range) and during big signal input, it is ensured that
Sensing probe always works near zero field, it is ensured that front end analogue channel circuit will not enter saturation state, will not produce phase
The change of shifting, thus the stability of phase-sensitive detection circuit output is also ensure that, therefore can be made by the frequency-selective amplifier of high-order
Significantly fundamental wave noise obtains very big suppression, and useful signal is got a promotion amplification, solves classical signal detection circuit
There is a problem of taking into account and ensure the resolution ratio of signal and allow big signal input.
Preferred embodiment of the present utility model is described in detail above in association with accompanying drawing, but, the utility model is not limited
Detail in above-mentioned implementation method, in range of the technology design of the present utility model, can be to skill of the present utility model
Art scheme carries out various simple variants, and these simple variants belong to protection domain of the present utility model.
It is further to note that each particular technique feature described in above-mentioned specific embodiment, in not lance
In the case of shield, can be combined by any suitable means.In order to avoid unnecessary repetition, the utility model is to each
Possible combination is planted no longer separately to illustrate.
Additionally, can also be combined between a variety of implementation methods of the present utility model, as long as it is not disobeyed
Thought of the present utility model is carried on the back, it should equally be considered as content disclosed in the utility model.
Claims (9)
1. a kind of signal deteching circuit of flux-gate magnetometer, the signal deteching circuit includes obtaining magnetic field from sensing probe (1)
The signalling channel of signal and the excitation passage to the sensing probe (1) output drive signal, the signalling channel are included successively
The probe input circuit (2) of connection, selective frequency amplifier circuit (3), phase-sensitive detection circuit (4), integrating circuit (5) and feedback circuit
(6), it is characterised in that the feedback circuit (6) includes：
First feedback network (61), is configured as linear feedback circuit；And
Second feedback network (62), it is in parallel with first feedback network (61), be configured as non-linear feedback circuit, and this
Two feedback networks (62) work when the magnetic field signal that the sensing probe (1) is detected reaches the maximum measurement range of relative observation
Make.
2. signal deteching circuit according to claim 1, it is characterised in that the feedback circuit (6) also includes：
The signal output part of adder (63), its described first feedback network (61) of connection and the second feedback network (62), is used for
Phase adduction exports the output signal of first feedback network (61) and the second feedback network (62).
3. signal deteching circuit according to claim 1 and 2, it is characterised in that first feedback network (61) includes
First resistor (611).
4. signal deteching circuit according to claim 1 and 2, it is characterised in that second feedback network (62) includes：
Breakover element (621), its described integrating circuit (5) of connection, and be configured as in the magnetic field of the sensing probe (1) detection
Signal is turned on when reaching the maximum measurement range of relative observation；
Amplifier (622), its input connects the breakover element (621), for when the breakover element (621) is turned on,
Amplify the output signal of the breakover element (621)；And
Second resistance (623), the output end of its connection amplifier (622).
5. signal deteching circuit according to claim 4, it is characterised in that the conducting voltage of the breakover element (621)
Equal to the maximum measurement range that the integrating circuit (5) reaches relative observation in the magnetic field signal that the sensing probe (1) is detected
When maximum available output power.
6. signal deteching circuit according to claim 5, it is characterised in that the signalling channel also includes and the integration
The amplitude limiter circuit of circuit (5) connection, the output voltage for making the integrating circuit (5) is limited in the integrating circuit (5) in institute
The magnetic field signal for stating sensing probe (1) detection reaches the model of maximum available output power during with respect to the maximum measurement range observed
In enclosing.
7. signal deteching circuit according to claim 4, it is characterised in that the breakover element (621) using voltage-stabiliser tube,
Piezo-resistance or voltage comparator.
8. signal deteching circuit according to claim 7, it is characterised in that the voltage-stabiliser tube uses bi-directional voltage stabilizing pipe, its
One end connects the output end of the integrating circuit (5), and the other end connects the positive input terminal of the amplifier (622), the amplification
The positive input terminal and negative input end of device (622) are respectively grounded respectively by resistance, and the negative input end of the amplifier (622) and its
Resistance is connected between output end.
9. a kind of flux-gate magnetometer, it is characterised in that the flux-gate magnetometer is provided with any one in claim 1 to 8
Described signal deteching circuit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201621270096.4U CN206193264U (en) | 2016-11-22 | 2016-11-22 | Flux -gate magnetometer's signal detection circuit and this flux -gate magnetometer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201621270096.4U CN206193264U (en) | 2016-11-22 | 2016-11-22 | Flux -gate magnetometer's signal detection circuit and this flux -gate magnetometer |
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| Publication Number | Publication Date |
|---|---|
| CN206193264U true CN206193264U (en) | 2017-05-24 |
Family
ID=58723883
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201621270096.4U Withdrawn - After Issue CN206193264U (en) | 2016-11-22 | 2016-11-22 | Flux -gate magnetometer's signal detection circuit and this flux -gate magnetometer |
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| CN (1) | CN206193264U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106443805A (en) * | 2016-11-22 | 2017-02-22 | 中国地震局地球物理研究所 | Signal detection circuit of magnetic-flux-gate magnetometer, and the magnetic-flux-gate magnetometer |
-
2016
- 2016-11-22 CN CN201621270096.4U patent/CN206193264U/en not_active Withdrawn - After Issue
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106443805A (en) * | 2016-11-22 | 2017-02-22 | 中国地震局地球物理研究所 | Signal detection circuit of magnetic-flux-gate magnetometer, and the magnetic-flux-gate magnetometer |
| CN106443805B (en) * | 2016-11-22 | 2019-02-19 | 中国地震局地球物理研究所 | A kind of signal deteching circuit and the flux-gate magnetometer of flux-gate magnetometer |
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| AV01 | Patent right actively abandoned |
Granted publication date: 20170524 Effective date of abandoning: 20190219 |
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| AV01 | Patent right actively abandoned |