CN108007603B - Multi-parameter distribution measuring system based on asymmetric double-core optical fiber - Google Patents
Multi-parameter distribution measuring system based on asymmetric double-core optical fiber Download PDFInfo
- Publication number
- CN108007603B CN108007603B CN201711361638.8A CN201711361638A CN108007603B CN 108007603 B CN108007603 B CN 108007603B CN 201711361638 A CN201711361638 A CN 201711361638A CN 108007603 B CN108007603 B CN 108007603B
- Authority
- CN
- China
- Prior art keywords
- core
- optical fiber
- coupler
- circulator
- double
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 239000013307 optical fiber Substances 0.000 title claims abstract description 81
- 238000005259 measurement Methods 0.000 claims abstract description 25
- 239000002344 surface layer Substances 0.000 claims abstract description 12
- 230000035945 sensitivity Effects 0.000 claims abstract description 5
- 239000011159 matrix material Substances 0.000 claims abstract description 4
- 239000000835 fiber Substances 0.000 claims description 49
- 238000000034 method Methods 0.000 claims description 4
- 230000003287 optical effect Effects 0.000 claims description 4
- 238000003491 array Methods 0.000 claims description 3
- 230000005540 biological transmission Effects 0.000 claims description 3
- 230000001808 coupling effect Effects 0.000 claims description 3
- 239000000126 substance Substances 0.000 claims description 2
- 230000011218 segmentation Effects 0.000 abstract description 2
- 238000005516 engineering process Methods 0.000 description 6
- 230000004044 response Effects 0.000 description 4
- 239000000523 sample Substances 0.000 description 4
- 238000001069 Raman spectroscopy Methods 0.000 description 3
- 238000012544 monitoring process Methods 0.000 description 3
- 238000000253 optical time-domain reflectometry Methods 0.000 description 3
- 238000011161 development Methods 0.000 description 2
- 230000018109 developmental process Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000000969 carrier Substances 0.000 description 1
- 239000012792 core layer Substances 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000010259 detection of temperature stimulus Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000010287 polarization Effects 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
- G01K11/00—Measuring temperature based upon physical or chemical changes not covered by groups G01K3/00, G01K5/00, G01K7/00 or G01K9/00
- G01K11/32—Measuring temperature based upon physical or chemical changes not covered by groups G01K3/00, G01K5/00, G01K7/00 or G01K9/00 using changes in transmittance, scattering or luminescence in optical fibres
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L1/00—Measuring force or stress, in general
- G01L1/24—Measuring force or stress, in general by measuring variations of optical properties of material when it is stressed, e.g. by photoelastic stress analysis using infrared, visible light, ultraviolet
- G01L1/242—Measuring force or stress, in general by measuring variations of optical properties of material when it is stressed, e.g. by photoelastic stress analysis using infrared, visible light, ultraviolet the material being an optical fibre
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Optical Transform (AREA)
- Length Measuring Devices By Optical Means (AREA)
Abstract
The invention relates to the technical field of multi-parameter distributed measurement systems, in particular to a multi-parameter distributed measurement system based on asymmetric double-core optical fibers. According to the invention, through the characteristic that the on-axis core and the surface layer core of the asymmetric double-core optical fiber have different sensitivity coefficients to temperature and strain, a temperature and strain solving matrix is constructed by using Rayleigh scattering signals of the double cores; the space segmentation positioning is carried out on Rayleigh scattering in the full optical fiber range by using the weak grating array, so that the space resolution and the measurement precision of the sensing system are improved, and the simultaneous accurate measurement of temperature and strain and the accurate positioning of the temperature and the strain in an interval are realized.
Description
Technical Field
The invention relates to the technical field of multi-parameter distributed measurement systems, in particular to a multi-parameter distributed measurement system based on asymmetric double-core optical fibers.
Background
With the development of scientific technology and the improvement of application requirements of the internet of things, an optical fiber sensing network is developing towards high-capacity and multi-parameter measurement, a distributed optical fiber sensing network based on Rayleigh scattering, Brillouin scattering and Raman scattering provides a feasible new means for measuring physical parameters such as temperature, strain and the like of various points continuously distributed in space in severe environments such as high voltage, strong magnetic field interference, large current, complex geometric space, flammability, explosiveness and the like, and the distributed optical fiber sensing technology is developed along with the generation of Optical Time Domain Reflectometry (OTDR), for example: measuring the intensity and polarization state of a backward Rayleigh scattering signal by using an optical time domain reflection technology to monitor temperature/strain; measuring the intensity of a backward Raman scattering signal by using an optical time domain reflection technology to monitor the temperature; temperature/strain is monitored by measuring the intensity and frequency shift of the brillouin signal using optical time domain reflectometry.
The distributed optical fiber sensor based on Brillouin scattering and the distributed optical fiber sensor based on Raman scattering have low response speed and spatial resolution, are not suitable for monitoring requirements of many application occasions on quick response of accidents, and the complex and expensive system also limits the engineering application of the two types of distributed measurement technologies. The distributed optical fiber sensor based on rayleigh scattering has a fast response speed and high sensitivity, and is beginning to be emphasized. However, the distributed optical fiber sensing system based on single-mode optical fiber rayleigh scattering uses weak backward rayleigh scattering signals as information carriers, the signal-to-noise ratio of the system is low, the measurement accuracy and the spatial resolution are low, the sensing function is single, quantitative detection of temperature and strain is difficult to realize, and the like, and the development of the distributed optical fiber sensing technology based on rayleigh scattering is restricted. Particularly, because the optical fiber is sensitive to the cross of temperature and strain, the optical fiber is difficult to be guaranteed not to be disturbed by stress by adding an additional temperature-sensing optical fiber, the measurement precision is difficult to be guaranteed due to the position deviation of the temperature compensation grating and the measurement grating, and the like, and the optical fiber is difficult to be applied in engineering. At present, no report that strain and temperature continuous distributed optical fiber sensing detection can be simultaneously carried out on all positions along an optical fiber by adopting a weak optical fiber grating array is available. If the strain, temperature and other measurements can be simultaneously and rapidly monitored in a distributed manner in a long distance, the monitoring cost can be greatly reduced, and the effectiveness and reliability of monitoring can be improved. Therefore, innovative sensing mechanisms and methods are needed to meet the requirements of practical applications.
Disclosure of Invention
Aiming at the problems, the invention provides a multi-parameter distributed measurement system based on asymmetric double-core optical fibers, which can realize high spatial resolution and high-precision distributed measurement of temperature and strain signals.
In order to achieve the purpose, the technical scheme adopted by the invention is as follows:
the utility model provides a many parameter distributed measurement system based on asymmetric two-core optical fiber, includes broadband light source, pulse modulator, first coupler, two-core optical fiber, first circulator, second circulator, the second coupler, the optical fiber delay line, first notch filter, second notch filter, first photodiode, second photodiode, third photodiode, information acquisition unit and computer, two-core optical fiber include on-axis core and surface layer core, be equipped with weak grating array on-axis core and the surface layer core respectively.
Further, the broadband light source is connected to a pulse modulator, the pulse modulator is connected to an input end of a first coupler of the first coupler, a first output end of the first coupler is connected to a first port of a first circulator of the first circulator, a second port of the first circulator is connected to a first input end of a dual-core fiber coupler of the dual-core fiber coupler, a first output end of the dual-core fiber coupler is coupled to an on-axis core of the dual-core fiber, and a second output end of the dual-core fiber coupler is coupled to a surface core of the dual-core fiber.
Further, a third port of the first circulator is connected to a first input end of a second coupler of the second coupler, a first output end of the second coupler is connected to a first port of the information acquisition unit through a first photodiode, and a second output end of the second coupler is connected to a second port of the information acquisition unit through a first notch filter and a second photodiode.
Further, a second output end of the first coupler is connected to a first port of a second circulator of the second circulator, a second port of the second circulator is connected to a second input end of the dual-core fiber coupler, and a third port of the second circulator is connected to a third port of the information acquisition unit through the fiber delay line, the second notch filter and the third photodiode.
Further, the information acquisition unit is connected to a computer, and the computer is connected to the pulse modulator.
Furthermore, the dual-core optical fiber is a transmission type dual-chip optical fiber, the on-axis core and the surface layer core have different sensitivity coefficients to pressure and temperature, and no coupling effect exists between the on-axis core and the surface layer core.
Furthermore, the weak grating array is an identical weak fiber grating, is manufactured by adopting the same mask plate, and has consistent central wavelength.
The invention has the beneficial effects that:
1. the method comprises the steps of exciting Rayleigh scattering light by using a modulated pulse light source to perform distributed measurement, performing space segmentation positioning on Rayleigh scattering in an all-fiber range by using pulses and weak grating arrays to improve the spatial resolution and the measurement precision of a sensing system, and constructing a temperature and strain solving matrix by using Rayleigh scattering signals of every two adjacent weak grating regions of a double-core fiber to realize simultaneous accurate measurement of temperature and strain and accurate positioning of the temperature and strain in the regions;
2. the distributed measurement is carried out by combining Rayleigh scattering and weak grating arrays in the double-core optical fiber, the measurement precision is high, the spatial resolution is high, and the simultaneous measurement of temperature and strain is realized on one optical fiber;
3. the distributed optical fiber sensing device has the advantages of simple structure, high response speed and high spatial resolution, and can simultaneously realize high-precision distributed optical fiber sensing measurement of temperature and strain parameters.
Drawings
FIG. 1 is a block diagram of a measurement system of the present invention;
FIG. 2 is a graph of time versus fiber length;
FIG. 3 is a graph of temperature versus time;
FIG. 4 is a plot of strain versus time;
FIG. 5 is a temperature distribution curve in the spatial domain;
fig. 6 is a strain distribution curve in the spatial domain.
1. A broadband light source; 2. a pulse modulator; 3. a first coupler; 301. a first coupler input; 302. a first coupler first output; 303. a first coupler second output; 4. a dual-core fiber coupler; 401. a first input end of the double-core optical fiber coupler; 402. a second input end of the double-core optical fiber coupler; 403. a first output end of the dual-core optical fiber coupler; 404. a second output end of the dual-core optical fiber coupler; 5. a dual-core optical fiber; 501. an on-axis core; 502. a skin core; 6. a weak grating array; 7. a first circulator; 701. a first circulator first port; 702. a first circulator second port; 703. a first circulator third port; 8. a second circulator; 801. a second circulator first port; 802. a second circulator second port; 803. a second circulator third port; 9. a second coupler; 901. a second coupler first input; 902. a second coupler first output; 903. a second coupler second output; 10. a fiber delay line; 11. a first notch filter; 12. a second notch filter; 13. a first photodiode; 14. a second photodiode; 15. a third photodiode; 16. an information acquisition unit; 1601. a first port of an information acquisition unit; 1602. a second port of the information acquisition unit; 1603. a third port of the information acquisition unit; 17. and (4) a computer.
Detailed Description
The technical solution of the present invention is described below with reference to the accompanying drawings and examples.
As shown in fig. 1, the multiparameter distributed measurement system based on the asymmetric dual-core fiber of the present invention includes a broadband light source 1, a pulse modulator 2, a first coupler 3, a dual-core fiber coupler 4, a dual-core fiber 5, a first circulator 7, a second circulator 8, a second coupler 9, a fiber delay line 10, a first notch filter 11, a second notch filter 12, a first photodiode 13, a second photodiode 14, a third photodiode 15, an information acquisition unit 16, and a computer 17, where the dual-core fiber 5 includes an on-axis core 501 and a surface core 502, and the on-axis core 501 and the surface core 502 are respectively provided with a weak grating array 6.
More specifically, the broadband light source 1 is connected to the pulse modulator 2, the pulse modulator 2 is connected to the first coupler input end 301 of the first coupler 3, and the broadband light output by the broadband light source 1 is output as pulsed light through the pulse modulator 2, input to the first coupler 3, and divided into a first beam of probe light and a second beam of probe light.
More specifically, the first coupler first output end 302 of the first coupler 3 is connected to the first circulator first port 701 of the first circulator 7, the first circulator second port 702 of the first circulator 7 is connected to the dual-core fiber coupler first input end 401 of the dual-core fiber coupler 4, the dual-core fiber coupler first output end 403 of the dual-core fiber coupler 4 is coupled to the on-axis core 501 of the dual-core fiber 5, the third port 703 of the first circulator 7 is connected to the first input port 901 of the second coupler 9, the first output port 902 of the second coupler 9 of the second coupler is connected to the first port 1601 of the information acquisition unit 16 through the first photodiode 13, and the second output port 903 of the second coupler 9 of the second coupler is connected to the second port 1602 of the information acquisition unit 16 through the first notch filter 11 and the second photodiode 14. By adopting the structure, the working principle is as follows: the first beam of probe light is incident on the first circulator first port 701 of the first circulator 7, is emitted from the first circulator second port 702 of the first circulator 7, enters the dual-core optical fiber coupler first input end 401 of the dual-core optical fiber coupler 4, is coupled into the on-axis core 501 of the dual-core optical fiber 5 from the dual-core optical fiber coupler first output end 403 of the dual-core optical fiber coupler 4, is incident on the dual-core optical fiber coupler first output end 403 of the dual-core optical fiber coupler 4 from the weak grating array 6 on the on-axis core 501 and the first reflected light generated by the rayleigh scattering effect, is emitted from the dual-core optical fiber coupler first input end 401 of the dual-core optical fiber coupler 4, is incident on the first circulator second port 702 of the first circulator 7, is emitted from the third port 703 of the first circulator 7, is subsequently incident on the second coupler 9, and is divided into two beams of on-axis core reflected light and on-axis core reflected light, the reflected light of the on-axis core grating is incident to the first photodiode 13 and converted into a grating electric signal, and then transmitted to the first port 1601 of the information acquisition unit 16, and the rayleigh reflected light of the on-axis core grating passes through the first notch filter 11, is incident to the second photodiode 14 and converted into a rayleigh electric signal, and then transmitted to the second port 1602 of the information acquisition unit 16.
More specifically, the first coupler second output end 303 of the first coupler 3 is connected to the second circulator first port 801 of the second circulator 8, the second circulator second port 802 of the second circulator 8 is connected to the two-core optical fiber coupler second input end 402 of the two-core optical fiber coupler 4, the two-core optical fiber coupler second output end 404 of the two-core optical fiber coupler 4 is coupled to the sheath core 502 of the two-core optical fiber 5, and the second circulator third port 803 of the second circulator 8 is connected to the information acquisition unit third port 1603 of the information acquisition unit 16 through the optical fiber delay line 10 and the second notch filter 12. By adopting the structure, the working principle is as follows: the second beam of probe light is incident on the second circulator first port 801 of the second circulator 8, exits from the second circulator second port 802 of the second circulator 8, enters the dual-core fiber coupler second input end 402 of the dual-core fiber coupler 4, is coupled into the sheath core 502 of the dual-core fiber 5 from the dual-core fiber coupler second output end 404 of the dual-core fiber coupler 4, enters the dual-core fiber coupler second output end 404 of the dual-core fiber coupler 4 through the weak grating array 6 on the sheath core 502 and the rayleigh scattering effect, exits from the dual-core fiber coupler second input end 402 of the dual-core fiber coupler 4, enters the second circulator second port 802 of the second circulator 8, exits from the second circulator third port 803 of the second circulator 8, enters the third photodiode 15 through the fiber delay line 10 and the second notch filter 12, and is converted into a sheath electrical signal, and then to the information gathering unit third port 1603 of the information gathering unit 16.
More specifically, the information acquisition unit 16 is connected to a computer 17, and the computer 17 is connected to the pulse modulator 2. With such a configuration, the three electrical signals collected by the information collecting unit 16 are finally transmitted to the computer 17 for signal processing for image display.
More specifically, the two-core optical fiber 5 is a transmission type two-chip optical fiber, the on-axis core 501 and the surface core 502 have different sensitivity coefficients to pressure and temperature, and there is no coupling effect between the on-axis core 501 and the surface core 502.
More specifically, the weak grating array 6 is an identical weak fiber grating, and is made of the same mask plate, and the central wavelengths are identical.
The invention also provides a measuring method of the multi-parameter distributed measuring system based on the asymmetric double-core optical fiber, which comprises the following steps:
step one, setting the pulse interval tau of a pulse modulator to be required to be longer than the time of transmitting a pulse in a double-core optical fiber, namely:
τ＞2nL/c
wherein n is the refractive index of the fiber core of the dual-core fiber, L is the length of the dual-core fiber, and c is the speed of light;
step two, the position of the weak fiber bragg grating (wFBG) can be calculated by using the pulse signal in the first grating electrical signal as follows:
d＝(t-t0)c/2n
where t is the time of receiving the corresponding pulse signal in the reference electrical signal, t0For the sending time of the square wave driving signal sent to the pulse modulator by the computer 17, a relation curve between time and weak grating distance, that is, a relation curve between time and optical fiber length can be obtained by a formula, as shown in fig. 2, so that each grating in the weak grating array can be positioned;
and step three, after the pulse enters the double-core optical fiber, Rayleigh scattering light with certain intensity is reflected back after passing through one point, so that Rayleigh scattering signals received by the optical detector are continuous and variable, and the light intensity received at a certain moment is related to the stress and the temperature at a certain position on the double-core optical fiber.
Step four, through simultaneous first Rayleigh electric signal I12And a second electrical signal I2Solving the matrix of (1):
wherein the content of the first and second substances,
the temperature sensitive coefficients of the on-axis core and the surface layer core of the double-core optical fiber are respectively,
strain sensitive coefficients of an on-axis core and a surface layer core of the dual-core optical fiber are respectively, and a relation curve of temperature and time can be obtained through a formula, as shown in fig. 3; strain versus time, as shown in fig. 4;
and step five, combining the obtained relation curve of time and optical fiber length, the obtained relation curve of temperature and time and the obtained relation curve of strain and time to obtain the respective distribution conditions of temperature and strain on the spatial domain, as shown in fig. 5 and 6.
While the present invention has been described with reference to the embodiments shown in the drawings, the present invention is not limited to the embodiments, which are illustrative and not restrictive, and those skilled in the art can make various modifications without departing from the spirit and scope of the present invention.
Claims (1)
1. A multi-parameter distributed measurement system based on asymmetric double-core optical fibers is characterized in that: the broadband optical fiber (1), a pulse modulator (2), a first coupler (3), a double-core optical fiber coupler (4), a double-core optical fiber (5), a first circulator (7), a second circulator (8), a second coupler (9), an optical fiber delay line (10), a first notch filter (11), a second notch filter (12), a first photodiode (13), a second photodiode (14), a third photodiode (15), an information acquisition unit (16) and a computer (17), wherein the double-core optical fiber (5) comprises an on-axis core (501) and a surface core (502), and weak grating arrays (6) are respectively arranged on the on-axis core (501) and the surface core (502),
the broadband light source (1) is connected with the pulse modulator (2), the pulse modulator (2) is connected with the first coupler input end (301) of the first coupler (3),
the first output end (302) of the first coupler (3) is connected to the first circulator first port (701) of the first circulator (7), the first circulator second port (702) of the first circulator (7) is connected to the first input end (401) of the dual-core fiber coupler (4), the first output end (403) of the dual-core fiber coupler (4) is coupled to the on-axis core (501) of the dual-core fiber (5), the second output end (404) of the dual-core fiber coupler (4) is coupled to the surface layer core (502) of the dual-core fiber (5),
a third port (703) of the first circulator (7) is connected to a first input end (901) of a second coupler of the second coupler (9), a first output end (902) of the second coupler (9) is connected to a first port (1601) of an information acquisition unit of the information acquisition unit (16) through a first photodiode (13), a second output end (903) of the second coupler (9) is connected to a second port (1602) of the information acquisition unit (16) through a first notch filter (11) and a second photodiode (14),
a second output end (303) of the first coupler (3) is connected with a first port (801) of a second circulator of the second circulator (8), a second port (802) of the second circulator (8) is connected with a second input end (402) of the double-core optical fiber coupler (4), a third port (803) of the second circulator (8) is connected with a third port (1603) of an information acquisition unit (16) through an optical fiber delay line (10), a second notch filter (12) and a third photodiode (15),
the information acquisition unit (16) is connected with a computer (17), and the computer (17) is connected with the pulse modulator (2); the double-core optical fiber (5) is a transmission type double-chip optical fiber, the on-axis core (501) and the surface layer core (502) have different sensitivity coefficients to pressure and temperature, and no coupling effect exists between the on-axis core (501) and the surface layer core (502); the weak grating array (6) is an identical weak fiber grating and is made of the same mask plate, and the central wavelengths are consistent;
the measuring method of the multi-parameter distributed measuring system based on the asymmetric double-core optical fiber comprises the following steps:
step one, setting the pulse interval tau of a pulse modulator to be required to be longer than the time of transmitting a pulse in a double-core optical fiber, namely:
τ＞2nL/c
wherein n is the refractive index of the fiber core of the dual-core fiber, L is the length of the dual-core fiber, and c is the speed of light;
step two, the position of the weak fiber bragg grating (wFBG) can be calculated by using the pulse signal in the first grating electrical signal as follows:
d＝(t-t0)c/2n
where t is the time of receiving the corresponding pulse signal in the reference electrical signal, t0For the sending time of a square wave driving signal sent to a pulse modulator by a computer (17), a relation curve between time and weak grating distance, namely a relation curve between time and optical fiber length can be obtained through a formula, so that each grating in a weak grating array can be positioned;
step three, after the pulse enters the double-core optical fiber, Rayleigh scattering light with certain intensity is reflected back after passing through one point, so that Rayleigh scattering signals received by the optical detector are continuous and variable, and the light intensity received at a certain moment is related to the stress and the temperature at a certain position on the double-core optical fiber;
step four, through simultaneous first Rayleigh electric signal I12And a second electrical signal I2Solving the matrix of (1):
wherein the content of the first and second substances,
the temperature sensitive coefficients of the on-axis core and the surface layer core of the double-core optical fiber are respectively,
strain sensitive coefficients of an on-axis core and a surface layer core of the double-core optical fiber are respectively obtained, and a temperature-time relation curve and a strain-time relation curve can be obtained through a formula;
and step five, combining the obtained relation curve of time and optical fiber length, the relation curve of temperature and time and the relation curve of strain and time to obtain the respective distribution conditions of temperature and strain on a spatial domain.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711361638.8A CN108007603B (en) | 2017-12-18 | 2017-12-18 | Multi-parameter distribution measuring system based on asymmetric double-core optical fiber |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711361638.8A CN108007603B (en) | 2017-12-18 | 2017-12-18 | Multi-parameter distribution measuring system based on asymmetric double-core optical fiber |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108007603A CN108007603A (en) | 2018-05-08 |
| CN108007603B true CN108007603B (en) | 2020-05-05 |
Family
ID=62059711
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201711361638.8A Active CN108007603B (en) | 2017-12-18 | 2017-12-18 | Multi-parameter distribution measuring system based on asymmetric double-core optical fiber |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108007603B (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108801304B (en) * | 2018-06-13 | 2019-11-26 | 武汉理工大学 | A method of improving Rayleigh scattering many reference amounts distributed measurement precision |
| CN113984126B (en) * | 2021-11-04 | 2024-05-14 | 武汉理工大学威海研究院 | Temperature strain monitoring system and method based on differently doped double-core weak reflection FBG array |
| CN114354974B (en) * | 2021-12-30 | 2023-06-16 | 广东工业大学 | Distributed wind speed sensor based on double-core optical fiber, measuring device and method |
| CN116989832B (en) * | 2023-09-26 | 2023-12-26 | 北京大学 | Variable multi-space sensing scale seismic exploration method and system |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1828229A (en) * | 2006-04-19 | 2006-09-06 | 黑龙江大学 | Time division multiplex optical fiber grating sensing testing system based on CPLD |
| CN105181111A (en) * | 2015-09-21 | 2015-12-23 | 电子科技大学 | Ultraweak fiber bragg grating array and Phi-OTDR combined optical fiber vibration sensing system |
| CN105698831A (en) * | 2016-01-26 | 2016-06-22 | 武汉理工大学 | Double-core FBG (fiber bragg grating) array sensing network and distributed sensing information obtaining method |
| CN107036733A (en) * | 2017-04-21 | 2017-08-11 | 武汉理工大学 | The many reference amounts Distributed Measurement System and measuring method of twin-core dim light grid array based on dark pulse light source |
-
2017
- 2017-12-18 CN CN201711361638.8A patent/CN108007603B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1828229A (en) * | 2006-04-19 | 2006-09-06 | 黑龙江大学 | Time division multiplex optical fiber grating sensing testing system based on CPLD |
| CN105181111A (en) * | 2015-09-21 | 2015-12-23 | 电子科技大学 | Ultraweak fiber bragg grating array and Phi-OTDR combined optical fiber vibration sensing system |
| CN105698831A (en) * | 2016-01-26 | 2016-06-22 | 武汉理工大学 | Double-core FBG (fiber bragg grating) array sensing network and distributed sensing information obtaining method |
| CN107036733A (en) * | 2017-04-21 | 2017-08-11 | 武汉理工大学 | The many reference amounts Distributed Measurement System and measuring method of twin-core dim light grid array based on dark pulse light source |
Also Published As
| Publication number | Publication date |
|---|---|
| CN108007603A (en) | 2018-05-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109238355B (en) | Device and method for simultaneously sensing and measuring distributed dynamic and static parameters of optical fiber | |
| CN108007603B (en) | Multi-parameter distribution measuring system based on asymmetric double-core optical fiber | |
| US6285446B1 (en) | Distributed sensing system | |
| CN107036733B (en) | The many reference amounts Distributed Measurement System and measurement method of twin-core dim light grid array based on dark pulse light source | |
| CN102506904B (en) | Spontaneous Brillouin scattering optical time domain reflectometer based on superconductive nanowire single-proton detector | |
| CN103364070B (en) | Fiber bragg grating vibration sensing system based on volume phase grating demodulation | |
| CN107238412B (en) | A kind of while monitoring vibration, stress, temperature distributed fiberoptic sensor | |
| CN103674117B (en) | Measure entirely method and device with weak optical fiber Bragg grating temperature and strain based on Raman scattering simultaneously | |
| CN102937416B (en) | A kind of fully distributed fiber switched based on orthogonal polarisation state strains and vibration sensing method and device | |
| CN105698871A (en) | Distributed strain and temperature simultaneous measurement device and distributed strain and temperature simultaneous measurement method based on optical frequency domain reflection | |
| CN102607621A (en) | Distributed optical fiber Brillouin sensing device and method thereof for detecting temperature and strain synchronously | |
| CN103591971B (en) | A kind of localization method of fiber grating | |
| CN108844614B (en) | Chaotic Brillouin optical correlation domain analysis system and method based on phase spectrum measurement | |
| CN106643832A (en) | Phase-sensitive optical time-domain reflectometer based on linear frequency-modulation pulse and measurement method of phase-sensitive optical time-domain reflectometer | |
| CN109959403B (en) | Multi-parameter large-capacity sensing system | |
| CN110307920B (en) | Optical fiber temperature and stress sensing system based on noise modulation and measuring method | |
| CN108760080B (en) | A kind of distributed fiber Raman temperature measuring equipment and method based on ASE noise | |
| CN102269573A (en) | Quasi-distributed composite structure strain and temperature detection system | |
| CN103940360A (en) | Strain monitoring device based on cascade chirped fiber gratings | |
| CN103575313A (en) | Multi-longitudinal mode annular cavity laser sensor frequency division multiplexing device based on beat frequency technology | |
| CN111811554A (en) | Optical cavity ring-down-based large-range high-precision fiber grating sensing method and device | |
| CN110806259A (en) | Device for high-frequency disturbance positioning and detection of optical fiber sensing | |
| CN107727122B (en) | Double-end detection combined Raman and Brillouin scattering distributed optical fiber sensing device | |
| CN104458080A (en) | Optical fiber pressure sensing measurement method and device | |
| CN203587125U (en) | Positioning system of fiber grating |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |