CN106772141A - Industrial frequency noise squelch device based on SQUID magnetometers - Google Patents
Industrial frequency noise squelch device based on SQUID magnetometers Download PDFInfo
- Publication number
- CN106772141A CN106772141A CN201710041852.9A CN201710041852A CN106772141A CN 106772141 A CN106772141 A CN 106772141A CN 201710041852 A CN201710041852 A CN 201710041852A CN 106772141 A CN106772141 A CN 106772141A
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- Prior art keywords
- squid
- frequency noise
- industrial frequency
- magnetometers
- gradiometers
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R33/00—Arrangements or instruments for measuring magnetic variables
- G01R33/02—Measuring direction or magnitude of magnetic fields or magnetic flux
- G01R33/035—Measuring direction or magnitude of magnetic fields or magnetic flux using superconductive devices
- G01R33/0354—SQUIDS
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R15/00—Details of measuring arrangements of the types provided for in groups G01R17/00 - G01R29/00, G01R33/00 - G01R33/26 or G01R35/00
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R33/00—Arrangements or instruments for measuring magnetic variables
- G01R33/007—Environmental aspects, e.g. temperature variations, radiation, stray fields
- G01R33/0082—Compensation, e.g. compensating for temperature changes
Abstract
The present invention provides a kind of industrial frequency noise squelch device based on SQUID magnetometers, including screened room, Dewar, SQUID gradiometers, SQUID magnetometers and reading circuit；The SQUID gradiometers and the SQUID magnetometers are arranged in the Dewar, and the Dewar and the reading circuit are arranged in the screened room；The SQUID gradiometers are used to detect the NMR signal in extremely low field nuclear magnetic resonance system；The SQUID magnetometers are used to detect the industrial frequency noise in environmental magnetic field；The reading circuit is used to read the output voltage of the SQUID gradiometers and the SQUID magnetometers, and treatment obtains the NMR signal after industrial frequency noise squelch.Industrial frequency noise squelch device based on SQUID magnetometers of the invention effectively inhibits industrial frequency noise to disturb, and improves the signal to noise ratio of NMR signal.
Description
Technical field
The present invention relates to the technical field of superconducting electronics, more particularly to a kind of power frequency based on SQUID magnetometers is made an uproar
Sound inhibitor.
Background technology
SPUID (Superconducting Quantum Interference Device, SQUID) is
A kind of extremely delicate that can measure faint magnetic signal, is functionally a kind of magnetic flux transducer, can not only be used
To measure the change of magnetic flux, other physical quantitys that can be converted to magnetic flux can also be measured, such as voltage, electric current, resistance, inductance,
Magnetic induction intensity, magnetic field gradient, magnetic susceptibility etc..The general principle of SQUID is built upon flux quautization and Josephson effect
On the basis of.According to the difference of bias current, it is divided into direct current and the class of radio frequency two.SQUID can be measured as detector
10-11The Weak magentic-field of Gauss, just corresponds to 1st/10000000000th of earth's magnetic field, improves several than conventional Magnetic Sensor sensitivity
The individual order of magnitude, is the underlying instrument equipment for carrying out the research of the material such as superconduction, nanometer, magnetic and semiconductor magnetic property, particularly
It is required to micro-examples such as film and nanometers.DC magnetic susceptibility signal is detected using SQUID detectors, sensitivity is reachable
10-8emu；Sample temperature excursion is 1.9K~400K；Change of magnetic field strength scope is 0~70000 Gauss.
Nuclear magnetic resonance technique is widely used in the fields such as Condensed Matter Physics, analytical chemistry, biology and medical science, is based on
The main field strength of the extremely low field nuclear magnetic resonance of SQUID is proved in detection heteronuclear scalar coupling, longitudinal direction in magnetic field of the earth magnitude
The aspects such as relaxation time weighted imaging have a clear superiority.
However, as shown in figure 1, power frequency and its harmonic wave interference in environmental magnetic field can have a strong impact on extremely low field nuclear magnetic resonance system
The NMR signal of sample in system, and then influence spectral line or image quality.
The content of the invention
The shortcoming of prior art in view of the above, it is an object of the invention to provide a kind of based on SQUID magnetometers
Industrial frequency noise squelch device, signalling channel is built by SQUID gradiometers, reference channel is built by SQUID magnetometers, using power frequency
Correlation of the harmonic wave in reference channel and signalling channel compensates the output of SQUID gradiometers, so that suppress industrial frequency noise interference,
Improve the signal to noise ratio of NMR signal.
In order to achieve the above objects and other related objects, the present invention provides a kind of industrial frequency noise based on SQUID magnetometers
Restraining device, is applied in extremely low field nuclear magnetic resonance system, including screened room, Dewar, SQUID gradiometers, SQUID magnetometers and
Reading circuit；The SQUID gradiometers and the SQUID magnetometers are arranged in the Dewar, the Dewar and the reading
Go out circuit to be arranged in the screened room；The screened room is used to shield the Radio frequency interference in environmental magnetic field；The Dewar is used
In storage cryogenic liquid with the low temperature environment needed for providing the SQUID gradiometers and SQUID magnetometers work；It is described
SQUID gradiometers are used to detect the NMR signal in extremely low field nuclear magnetic resonance system；The SQUID magnetometers are used to detect
Industrial frequency noise in environmental magnetic field；The reading circuit is connected with the SQUID gradiometers and the SQUID magnetometers respectively,
Output voltage for reading the SQUID gradiometers and the SQUID magnetometers, and process obtain industrial frequency noise squelch after
NMR signal.
In one embodiment of the invention, the SQUID gradients are calculated as First-order Gradient meter, two gradiometers or multistage gradient
Meter.
In one embodiment of the invention, the SQUID gradiometers include gradiometer antenna, antenna holder and SQUID chips；
The gradiometer antenna is wound on the antenna holder, and is fixed with the SQUID chips by epoxide component.
In one embodiment of the invention, the antenna holder is made up of ceramics.
In one embodiment of the invention, the SQUID magnetometers include search coil, epoxy rods and SQUID chips；It is described
Search coil is wound in the epoxy rods, is fixed with the SQUID chips by epoxide component.
In one embodiment of the invention, the reading circuit is by low temperature line and the SQUID with radio shielding layer
Gradiometer and the SQUID magnetometers are respectively connected with.
In one embodiment of the invention, by thunder, connector is not fixed on the Dewar plug of the Dewar to the reading circuit
On.
In one embodiment of the invention, epoxy plate, the SQUID magnetometers and the SQUID are provided with the Dewar
Gradiometer is each attached on the epoxy plate, and the epoxy plate is fixed on the Dewar of the Dewar beyond the Great Wall.
In one embodiment of the invention, the reading circuit includes magnetic flux lock-in circuit and control circuit；The magnetic flux lock
Circuit is determined for providing operating current to the SQUID gradiometers and the SQUID magnetometers；The control circuit is used to control
The size of provided operating current.
In one embodiment of the invention, the NMR signal that the reading circuit detects the SQUID gradiometers
The industrial frequency noise that the SQUID magnetometers are detected is subtracted, the NMR signal after industrial frequency noise squelch is obtained.
As described above, the industrial frequency noise squelch device based on SQUID magnetometers of the invention, has the advantages that：
(1) signalling channel is built by SQUID gradiometers, reference channel is built by SQUID magnetometers, existed using industrial frequency harmonic
The output of the tested SQUID gradiometers of correlation compensation in reference channel and signalling channel, suppresses industrial frequency noise interference；
(2) it is obviously improved the signal to noise ratio of NMR signal in extremely low field nuclear magnetic resonance system；
(3) the industrial frequency harmonic interference noise of frequency range about 1kHz -6kHz can be suppressed.
Brief description of the drawings
Fig. 1 is shown as the industrial frequency harmonic noise schematic diagram in environmental magnetic field in the prior art；
Fig. 2 is shown as the structural representation of the industrial frequency noise squelch device based on SQUID magnetometers of the invention；
Fig. 3 is shown as the industrial frequency noise squelch device based on SQUID magnetometers of the invention nuclear magnetic resonance before and after to be believed
Number contrast schematic diagram.
Component label instructions
1 screened room
2 Dewars
3 SQUID gradiometers
4 SQUID magnetometers
5 reading circuits
Specific embodiment
Embodiments of the present invention are illustrated below by way of specific instantiation, those skilled in the art can be by this specification
Disclosed content understands other advantages of the invention and effect easily.The present invention can also be by specific realities different in addition
The mode of applying is embodied or practiced, the various details in this specification can also based on different viewpoints with application, without departing from
Various modifications or alterations are carried out under spirit of the invention.
It should be noted that the diagram provided in the present embodiment only illustrates basic conception of the invention in a schematic way,
Then component count, shape and size when only display is with relevant component in the present invention rather than according to actual implementation in schema are painted
System, it is actual when the implementing kenel of each component, quantity and ratio can be a kind of random change, and its assembly layout kenel also may be used
Can be increasingly complex.
As shown in Fig. 2 the industrial frequency noise squelch device based on SQUID magnetometers of the invention, is applied to extremely low field nuclear-magnetism
In resonator system, including screened room 1, Dewar 2, SQUID gradiometers 3, SQUID magnetometers 4 and reading circuit 5.SQUID gradiometers
3 and SQUID magnetometers 4 are arranged in Dewar 2, and Dewar 2 and reading circuit 5 are arranged in screened room 1.Preferably, it is extremely low
Field refers to that magnetic field intensity is less than 2.5 Gausses.
Screened room 1 is used to shield the Radio frequency interference in environmental magnetic field.Specifically, screened room 1 can both shield environmental magnetic field
In Radio frequency interference, such as broadcast station signal, radar signal, mobile phone signal etc., it is also possible to suppress the low frequency in environmental magnetic field
Magnetic fluctuation, so as to avoid highly sensitive SQUID magnetometers output saturation.
Dewar 2 is used to storing cryogenic liquid to provide SQUID gradiometers 3 and SQUID magnetometers 4 work required low temperature ring
Border.Preferably, Dewar 2 includes Dewar bucket and Dewar plug, and the cryogenic liquid for being provided with low temperature environment, such as liquid are placed in Dewar bucket
Helium.
SQUID gradiometers 3 are used to detect the NMR signal in extremely low field nuclear magnetic resonance system.Preferably, SQUID ladders
Degree meter 3 is First-order Gradient meter, two gradiometers or multistage gradiometer.
SQUID magnetometers 4 are used to detect the industrial frequency noise in environmental magnetic field.
Reading circuit 5 is connected with SQUID gradiometers 3 and SQUID magnetometers 4 respectively, for reading the He of SQUID gradiometers 3
The output voltage of SQUID magnetometers 4, and treatment obtains the NMR signal after industrial frequency noise squelch.Due to SQUID magnetometers
The industrial frequency harmonic noise contained in 4 industrial frequency noises for detecting and SQUID gradiometers 3 has a uniformity of height, therefore SQUID magnetic
The industrial frequency noises that strong meter 4 is detected can effectively eliminate the work in the Nmr Lines that SQUID gradiometers 3 detect or image
Frequency noise, so as to significantly improve the signal to noise ratio of the NMR signal acquired in SQUID gradiometers 3.Specifically, by SQUID ladders
The NMR signal that degree meter 3 is detected subtracts the industrial frequency noise that SQUID magnetometers 4 are detected, you can the power frequency that is inhibited is made an uproar
NMR signal after sound, so as to significantly improve the signal to noise ratio of NMR signal.As shown in figure 3, lower curve is SQUID
The NMR signal that gradiometer 3 is obtained；Top curve suppresses the nuclear magnetic resonance after industrial frequency noise via SQUID magnetometers 4 and believes
Number.As seen from the figure, after being processed through the industrial frequency noise squelch device based on SQUID magnetometers of the invention, the institute of SQUID gradiometers 3
Industrial frequency noise in the NMR signal of acquisition is significantly suppressed, so as to improve its signal to noise ratio.
In one embodiment of the invention, SQUID gradiometers include gradiometer antenna, antenna holder and SQUID chips；Gradient
Meter antenna is wound on antenna holder, and is fixed with SQUID chips by epoxide component.Preferably, gradiometer antenna is by niobium line
Coiling is integrated on silicon chip；Antenna holder is made up of ceramics.When the nuclear-magnetism for needing to detect multiple SQUID gradiometers simultaneously
When resonance signal carries out industrial frequency noise squelch, multiple SQUID gradiometers can be set in Dewar.
In one embodiment of the invention, SQUID magnetometers include search coil, epoxy rods and SQUID chips；Search coil
It is wound in epoxy rods, is fixed with SQUID chips by epoxide component.Preferably, a diameter of 1mm of epoxy rods；Search coil
By the coiling of niobium line or it is integrated on silicon chip.The direction of search coil must be consistent with the detection direction of SQUID gradiometers.
In one embodiment of the invention, reading circuit includes magnetic flux lock-in circuit and control circuit.Magnetic flux lock-in circuit is used
In offer operating current to SQUID gradiometers and SQUID magnetometers；Control circuit is used to control to provide the big of operating current
It is small, to ensure that SQUID gradiometers and SQUID magnetometers being capable of normal works.
Preferably, epoxy plate is provided with Dewar, SQUID magnetometers are each attached on epoxy plate with SQUID gradiometers, ring
Oxygen plate is fixed on the Dewar of Dewar beyond the Great Wall.
In one embodiment of the invention, reading circuit by low temperature line and the SQUID gradiometers with radio shielding layer and
SQUID magnetometers are respectively connected with, so as to improve the electromagnetic compatibility and adaptive capacity to environment of superelectron equipment.Preferably, read
Circuit by the core thunder of standard 10 Dewar that connector is not fixed on Dewar beyond the Great Wall, to reduce the length of low temperature line.
In sum, the industrial frequency noise squelch device based on SQUID magnetometers of the invention is built by SQUID gradiometers and believed
Number passage, reference channel is built by SQUID magnetometers, and the correlation using industrial frequency harmonic in reference channel and signalling channel is mended
The output of SQUID gradiometers is repaid, suppresses industrial frequency noise interference；It is obviously improved the noise of the NMR signal of SQUID gradiometers
Than；The industrial frequency harmonic interference noise of frequency range about 1kHz -6kHz can be suppressed.So, the present invention effectively overcomes existing
Various shortcoming in technology and have high industrial utilization.
The above-described embodiments merely illustrate the principles and effects of the present invention, not for the limitation present invention.It is any ripe
The personage for knowing this technology all can carry out modifications and changes under without prejudice to spirit and scope of the invention to above-described embodiment.Cause
This, those of ordinary skill in the art is complete with institute under technological thought without departing from disclosed spirit such as
Into all equivalent modifications or change, should be covered by claim of the invention.
Claims (10)
1. a kind of industrial frequency noise squelch device based on SQUID magnetometers, it is characterised in that：It is applied to extremely low field nuclear magnetic resonance system
In system, including screened room, Dewar, SQUID gradiometers, SQUID magnetometers and reading circuit；SQUID gradiometers and described
SQUID magnetometers are arranged in the Dewar, and the Dewar and the reading circuit are arranged in the screened room；
The screened room is used to shield the Radio frequency interference in environmental magnetic field；
The Dewar be used for store cryogenic liquid with provide the SQUID gradiometers and the SQUID magnetometers work needed for
Low temperature environment；
The SQUID gradiometers are used to detect the NMR signal in extremely low field nuclear magnetic resonance system；
The SQUID magnetometers are used to detect the industrial frequency noise in environmental magnetic field；
The reading circuit is connected with the SQUID gradiometers and the SQUID magnetometers respectively, for reading the SQUID
The output voltage of gradiometer and the SQUID magnetometers, and treatment obtains the NMR signal after industrial frequency noise squelch.
2. the industrial frequency noise squelch device based on SQUID magnetometers according to claim 1, it is characterised in that：It is described
SQUID gradients are calculated as First-order Gradient meter, two gradiometers or multistage gradiometer.
3. the industrial frequency noise squelch device based on SQUID magnetometers according to claim 1, it is characterised in that：It is described
SQUID gradiometers include gradiometer antenna, antenna holder and SQUID chips；The gradiometer antenna is wound on the antenna branch
On frame, and fixed with the SQUID chips by epoxide component.
4. the industrial frequency noise squelch device based on SQUID magnetometers according to claim 3, it is characterised in that：The day
Line bracket is made up of ceramics.
5. the industrial frequency noise squelch device based on SQUID magnetometers according to claim 1, it is characterised in that：It is described
SQUID magnetometers include search coil, epoxy rods and SQUID chips；The search coil is wound in the epoxy rods, is passed through
Epoxide component is fixed with the SQUID chips.
6. the industrial frequency noise squelch device based on SQUID magnetometers according to claim 1, it is characterised in that：The reading
Go out circuit to be respectively connected with the SQUID gradiometers and the SQUID magnetometers by the low temperature line with radio shielding layer.
7. the industrial frequency noise squelch device based on SQUID magnetometers according to claim 1, it is characterised in that：The reading
Go out circuit by the thunder Dewar that connector is not fixed on the Dewar beyond the Great Wall.
8. the industrial frequency noise squelch device based on SQUID magnetometers according to claim 1, it is characterised in that：Du
Epoxy plate is provided with watt, the SQUID magnetometers are each attached on the epoxy plate with the SQUID gradiometers, the ring
Oxygen plate is fixed on the Dewar of the Dewar beyond the Great Wall.
9. the industrial frequency noise squelch device based on SQUID magnetometers according to claim 1, it is characterised in that：The reading
Going out circuit includes magnetic flux lock-in circuit and control circuit；The magnetic flux lock-in circuit is used to provide operating current to the SQUID
Gradiometer and the SQUID magnetometers；The control circuit is used for the size for controlling to provide operating current.
10. the industrial frequency noise squelch device based on SQUID magnetometers according to claim 1, it is characterised in that：The reading
Go out circuit the NMR signal that the SQUID gradiometers are detected subtracted into the power frequency that the SQUID magnetometers detect to make an uproar
Sound, obtains the NMR signal after industrial frequency noise squelch.
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| CN201710041852.9A CN106772141A (en) | 2017-01-20 | 2017-01-20 | Industrial frequency noise squelch device based on SQUID magnetometers |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109283476A (en) * | 2018-09-07 | 2019-01-29 | 中国科学院上海微系统与信息技术研究所 | The low frequency intrinsic noise test macro and test method of Magnetic Sensor |
| CN113008155A (en) * | 2021-03-03 | 2021-06-22 | 哈尔滨工业大学 | Fiber grating and piezoelectric ceramic combined magnetic noise suppression active vibration isolation device |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101477211A (en) * | 2009-01-22 | 2009-07-08 | 北京老村科技发展有限公司 | Magnetic anomaly detection system |
| CN103744035A (en) * | 2014-01-25 | 2014-04-23 | 吉林大学 | Working point migrated counter-type superconducting magnetometer and method for determining magnetic field change direction |
| CN105022005A (en) * | 2014-04-23 | 2015-11-04 | 中国科学院上海微系统与信息技术研究所 | SQUID magnetic sensor measuring sensitivity enhancement method, device and system |
| CN105203978A (en) * | 2014-06-03 | 2015-12-30 | 中国科学院上海微系统与信息技术研究所 | Lock-losing reset compensation device and method of SQUID magnetic sensor |
| CN105866710A (en) * | 2016-03-30 | 2016-08-17 | 中国科学院上海微系统与信息技术研究所 | Environmental noise suppression method and equipment |
-
2017
- 2017-01-20 CN CN201710041852.9A patent/CN106772141A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101477211A (en) * | 2009-01-22 | 2009-07-08 | 北京老村科技发展有限公司 | Magnetic anomaly detection system |
| CN103744035A (en) * | 2014-01-25 | 2014-04-23 | 吉林大学 | Working point migrated counter-type superconducting magnetometer and method for determining magnetic field change direction |
| CN105022005A (en) * | 2014-04-23 | 2015-11-04 | 中国科学院上海微系统与信息技术研究所 | SQUID magnetic sensor measuring sensitivity enhancement method, device and system |
| CN105203978A (en) * | 2014-06-03 | 2015-12-30 | 中国科学院上海微系统与信息技术研究所 | Lock-losing reset compensation device and method of SQUID magnetic sensor |
| CN105866710A (en) * | 2016-03-30 | 2016-08-17 | 中国科学院上海微系统与信息技术研究所 | Environmental noise suppression method and equipment |
Non-Patent Citations (1)
| Title |
|---|
| 章立源 等: "《超导物理学》", 31 May 1995, 电子工业出版社 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109283476A (en) * | 2018-09-07 | 2019-01-29 | 中国科学院上海微系统与信息技术研究所 | The low frequency intrinsic noise test macro and test method of Magnetic Sensor |
| CN113008155A (en) * | 2021-03-03 | 2021-06-22 | 哈尔滨工业大学 | Fiber grating and piezoelectric ceramic combined magnetic noise suppression active vibration isolation device |
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Application publication date: 20170531 |