CN114526684B - Brillouin optical time domain reflection temperature and strain detection device with chaotic external modulation - Google Patents
Brillouin optical time domain reflection temperature and strain detection device with chaotic external modulation Download PDFInfo
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
- G01B11/16—Measuring arrangements characterised by the use of optical techniques for measuring the deformation in a solid, e.g. optical strain gauge
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- 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
- G01K11/322—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 using Brillouin scattering
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Abstract
The invention relates to a Brillouin optical time domain reflection temperature and strain detection device with chaotic external modulation, belonging to the technical field of distributed optical fiber sensing; the problem of cross sensitivity of the Brillouin optical time domain reflectometer in simultaneous measurement of temperature and strain is solved; the Brillouin backscattering intensity is represented by the ratio of the Rayleigh backscattering intensity and the Brillouin backscattering intensity through measuring the Brillouin backscattering intensity, the Rayleigh backscattering intensity and the Brillouin frequency shift information in the sensing optical fiber, so that the simultaneous measurement of temperature and strain is realized; the coherent Rayleigh noise existing in the system is greatly suppressed by carrying out chaotic external modulation on the narrow linewidth laser signal, so that the signal-to-noise ratio of the system is improved, and high-precision detection on temperature and strain is realized; chaotic cross-correlation is carried out on the detection optical signal and the reference optical signal, so that high spatial resolution detection is realized; the invention can be applied to the fields of cable icing monitoring, perimeter security protection, gas pipeline security detection and the like.
Description
Technical Field
The invention relates to a Brillouin optical time domain reflectometer, belongs to the technical field of distributed optical fiber sensing, and particularly relates to a Brillouin optical time domain reflection temperature and strain detection device with chaotic external modulation.
Background
In recent years, the Brillouin optical time domain reflectometer has the advantages of single-ended injection, electromagnetic interference resistance, corrosion resistance and the like, and is widely applied to the fields of cable icing monitoring, perimeter security protection, gas pipeline security detection and the like. Because of the cross-sensitivity problem, the brillouin optical time domain reflectometer is only used for single-parameter measurement of temperature or strain for a long time, and along with the development of the technology level, an optical fiber sensing system for single-parameter measurement cannot meet the practical application requirement. In the existing cross-sensitive problem solution, the scheme for paving the double-path sensing optical fiber has the problems of difficult construction and higher cost; the scheme of setting the dual-parameter matrix demodulation temperature and strain by utilizing the Brillouin scattering spectrum features has the problems of larger influence by external environment and insufficient measurement accuracy. The use of brillouin combined raman scattering is a practical solution to the cross-sensitivity problem, but in the conventional solution, due to the influence of noise such as coherent rayleigh noise, there is a problem that signal-to-noise ratio in the system is low. Therefore, the measurement accuracy and the signal-to-noise ratio of the system are improved, and the problem that the simultaneous measurement of temperature and strain is urgently needed to be solved is solved by the Brillouin combined Raman scattering.
Disclosure of Invention
The invention aims to overcome the defects in the prior art, and solves the technical problems that: the hardware structure of the Brillouin optical time domain reflection temperature and strain detection device is improved by chaotic external modulation.
In order to solve the technical problems, the invention adopts the following technical scheme: the Brillouin optical time domain reflection temperature and strain detection device comprises a narrow linewidth chaotic external modulation laser module, an optical fiber back scattering optical signal acquisition module, a Rayleigh back scattering optical intensity information acquisition module, a Brillouin frequency shift information, a temperature/strain position information acquisition module and a signal processing module, wherein the narrow linewidth chaotic external modulation laser module modulates a continuous narrow linewidth laser signal into a narrow linewidth chaotic signal, then enters the optical fiber back scattering optical signal acquisition module, obtains a Brillouin back scattering optical signal and a Rayleigh back scattering optical signal in an optical fiber, the Rayleigh back scattering optical signal is input into the Rayleigh back scattering optical intensity information acquisition module to obtain Rayleigh back scattering optical intensity information and is transmitted to the signal processing module, and the Brillouin back scattering optical intensity information is input into the Brillouin back scattering optical intensity information acquisition module to be transmitted to the signal processing module, and the Brillouin frequency shift information obtained through the Brillouin frequency shift information and the temperature/strain position information acquisition module and the temperature/strain position information obtained through the chaotic cross-correlation processing module are transmitted to the signal processing module.
The narrow linewidth chaotic external modulation laser module comprises a narrow linewidth laser, an electro-optical modulation module, a first optical coupler, a spontaneous radiation source, a second optical circulator, a fourth optical filter, a tunable optical attenuator, a third optical circulator, a semiconductor laser and a fifth photoelectric detector, wherein the output end of the spontaneous radiation source is connected with the a end of the second optical circulator, the fourth optical filter is connected with the b end of the second optical circulator, the c end of the second optical circulator is connected with the a end of the third optical circulator through the tunable optical attenuator, the semiconductor laser is connected with the b end of the third optical circulator, the c end of the third optical circulator is connected with the electro-optical modulation module through the fifth photoelectric detector, a continuous optical signal output by the narrow linewidth laser is modulated into chaotic light outside the electro-optical modulation module, the output end of the electro-optical modulation module is connected with the a end of the first optical coupler, the chaotic light signal is divided into a detection light path and a reference light path, and the acquisition optical signal is respectively input into an optical fiber backward scattered light signal acquisition module, a Brillouin frequency shift information module and a temperature/strain position information module.
The optical fiber backscattering optical signal acquisition module comprises a pulse optical modulation module, a first optical amplifier, a first optical filter, a first optical circulator, a sensing optical fiber, a second optical amplifier, a second optical filter, a scrambler, a second optical coupler and a third optical coupler, wherein a b end of the first optical coupler outputs a first path of optical signal serving as detection light, the first path of optical signal is sequentially input into an a end of the first optical circulator through the pulse optical modulation module, the first optical amplifier and the first optical filter, a b end of the first optical circulator is connected with the sensing optical fiber to obtain a Brillouin backscattering optical signal and a Rayleigh backscattering optical signal in the optical fiber, the backscattering optical signal is output through a c end of the first optical circulator, then is transmitted to an a end of the third optical coupler through the second optical amplifier and the second optical filter, light output from the third optical coupler is divided into two paths, the Brillouin backscattering optical intensity information acquisition module, the Brillouin backscattering optical frequency shift information and the temperature/strain position information are respectively input into a reference optical frequency shift module and a second optical coupler, and a temperature/strain position information is acquired by the second optical coupler and the optical coupler is input into a position information through the second optical coupler.
The Rayleigh backward scattered light intensity information acquisition module comprises a first photoelectric detector and a low-pass filter, and a first path of light output by the c end of the third optical coupler is input to the input end of the first photoelectric detector; the output end of the first photoelectric detector is connected with the input end of the low-pass filter, and the signals are input into the signal processing module after the Rayleigh back-scattered light signals are filtered out, so that the Rayleigh back-scattered light intensity information is acquired.
The Brillouin back scattering light intensity information acquisition module comprises a tunable filter, a third optical amplifier, a third optical filter, a fourth optical coupler and a second photoelectric detector, wherein the second path of light output by the b end of the third optical coupler is filtered out by the tunable filter, a Brillouin back scattering light signal is input into the a end of the fourth optical coupler through the third optical amplifier and the third optical filter in sequence, the fourth optical coupler divides light into two paths, and the first path of light output by the c end of the fourth optical coupler is input into the signal processing module through the second photoelectric detector, so that the Brillouin back scattering intensity information is acquired.
The Brillouin frequency shift information and temperature/strain position information acquisition module comprises a fifth optical coupler, a third photoelectric detector, a mixer, a microwave source and a fourth photoelectric detector, wherein the output light of the second optical coupler is divided into two paths, the first path of light output by the c end of the second optical coupler and the second path of light output by the b end of the fourth optical coupler are respectively input into the a end and the b end of the fifth optical coupler for beat frequency treatment, the light output by the c end of the fifth optical coupler is input into the a end of the mixer through the third photoelectric detector, the b end of the mixer is connected with the microwave source, signals output by the third photoelectric detector and signals output by the microwave source are shifted in the mixer, and the c end of the mixer is connected with the first input end of the analog-digital conversion module; the second path of light output by the b end of the second optical coupler is input into the signal processing module through the fourth photoelectric detector.
The signal processing module comprises an FPGA module, an analog-to-digital conversion module and a data acquisition processing module, wherein the input end of the analog-to-digital conversion module is respectively connected with the C end of the mixer and the output end of the fourth photoelectric detector, the output end of the analog-to-digital conversion module is connected with the FPGA module, chaotic cross-correlation processing is carried out in the FPGA module, temperature/strain position information is demodulated based on cross-correlation peaks, then the temperature/strain position information is accessed into the C end of the data acquisition processing module, brillouin frequency shift information is demodulated in the data acquisition processing module, the A end of the data acquisition processing module is connected with the output end of the low-pass filter, and the B end of the data acquisition processing module is connected with the output end of the second photoelectric detector.
Compared with the prior art, the invention has the following beneficial effects:
1. according to the invention, the narrow linewidth laser signal is modulated into the chaotic light, the measurement precision of the Brillouin frequency shift is ensured by the narrow linewidth, the spatial resolution depends on the detection pulse width, and the full width at half maximum of the chaotic cross correlation peak influences the spatial resolution of the system, so that the method is not limited by the detection pulse width on the spatial resolution of the system, and high-spatial resolution and high-precision detection can be realized;
2. according to the invention, the narrow linewidth laser signal is modulated into the narrow linewidth chaotic signal, so that coherent Rayleigh noise existing in the system is well suppressed when the narrow linewidth laser signal is used as detection light, the signal-to-noise ratio of the system is improved, and high-precision detection of temperature and strain is realized;
3. according to the invention, the loss of the intensity of the Brillouin back scattering light in the optical fiber is compensated by detecting the intensity information of the Rayleigh back scattering light, and the frequency shift information and the intensity information of the Brillouin back scattering light are detected, so that the characteristic that the frequency shift information and the intensity information of the back scattering light are sensitive to temperature and strain simultaneously is utilized, the cross sensitivity problem is solved, and the simultaneous measurement of the temperature and the strain is realized.
Drawings
The invention is further described below with reference to the accompanying drawings:
FIG. 1 is a schematic diagram of the structure of the present invention;
in the figure: 1. the optical modulator comprises a narrow linewidth laser 2, an electro-optical modulation module 3, a first optical coupler 4, a pulse optical modulation module 5, a first optical amplifier 6, a first optical filter 7, a first optical circulator 8, a sensing optical fiber 9, a second optical amplifier 10, a second optical filter 11, a scrambler 12, a second optical coupler 13, a third optical coupler 14, a first photoelectric detector 15, a low-pass filter 16, a tunable filter 17, a third optical amplifier 18, a third optical filter 19, a fourth optical coupler 20, a second photoelectric detector 21, a fifth optical coupler 22, a third photoelectric detector 23, a mixer 24, a microwave source 25, an FPGA module 26, a fourth photoelectric detector 27, an analog-to-digital conversion module 28, a spontaneous emission source 29, a second optical circulator 30, a fourth optical filter 31, a tunable optical attenuator 32, a third optical circulator 33, a semiconductor laser 34, a fifth photoelectric detector 35 and a data acquisition processing module.
Detailed Description
As shown in FIG. 1, the invention provides a Brillouin optical time domain reflection temperature and strain detection device based on chaotic external modulation. The cross sensitivity problem of temperature and strain is overcome by simultaneously detecting the conditions of the intensity of the Brillouin backward scattering light, the intensity of the Rayleigh backward scattering light and the Brillouin frequency shift, and the simultaneous measurement of the temperature and the strain is realized; high-precision and high-spatial resolution measurement of temperature and strain is ensured by the chaos cross-correlation principle. The optical fiber array comprises a narrow linewidth laser 1, an electro-optical modulation module 2, a first optical coupler 3, a pulse optical modulation module 4, a first optical amplifier 5, a first optical filter 6, a first optical circulator 7, a sensing optical fiber 8, a second optical amplifier 9, a second optical filter 10, a scrambler 11, a second optical coupler 12, a third optical coupler 13, a first photoelectric detector 14, a low-pass filter 15, a tunable filter 16, a third optical amplifier 17, a third optical filter 18, a fourth optical coupler 19, a second photoelectric detector 20, a fifth optical coupler 21, a third photoelectric detector 22, a mixer 23, a microwave source 24, an FPGA module 25, a fourth photoelectric detector 26, an analog-to-digital conversion module 27, a spontaneous emission source 28, a second optical circulator 29, a fourth optical filter 30, a tunable optical attenuator 31, a third optical circulator 32, a semiconductor laser 33, a fifth photoelectric detector 34 and a data acquisition processing module 35.
Fig. 1 is a schematic structural diagram of a brillouin optical time domain reflection temperature strain simultaneous detection device based on chaotic external modulation according to the present invention, and a specific embodiment of the present invention is described below with reference to fig. 1:
the optical path is divided into A, B, C paths according to the difference of the detection data.
The narrow linewidth laser 1 emits 1550nm laser signals, and the output end of the narrow linewidth laser is connected with the input end of the electro-optic modulation module 2; the light generated by the spontaneous emission source 28 is connected with the a end of the second optical circulator 29, and the b end of the light is connected with the fourth optical filter 30 to filter out amplified spontaneous emission noise; the c-end of the second optical circulator 29 is connected to the adjustable optical attenuator 31 to reduce the power, an optical signal with proper power is input to the a-end of the third optical circulator 32, the b-end of the third optical circulator 32 is connected to the semiconductor laser 33 to generate a chaotic laser signal, the c-end of the third optical circulator 32 is connected to the electro-optical modulation module 2 through the fifth photodetector 34, the generated chaotic laser signal is used for externally modulating the electro-optical modulation module 2, and the 1550nm laser signal emitted by the narrow-linewidth laser 1 is modulated into chaotic light. The output end of the electro-optical modulation module 2 is connected with the end a of the first optical coupler 3, and the chaotic optical signal is divided into a detection optical path with the optical power accounting for 80% and a reference optical path with the optical power accounting for 20%; the b end of the first optical coupler 3 is connected with the input end of the pulse optical modulation module 4, and chaotic light signals are modulated into chaotic pulse light; the output end of the pulse light modulation module 4 is connected with the input end of the first optical amplifier 5, and the pulse light power is amplified; the output end of the first optical amplifier 5 is connected with the input end of the first optical filter 6, and spontaneous radiation noise is filtered out; the output end of the first optical filter 6 is connected with the input end a end of the first optical circulator 7; the reflection end b of the first optical circulator 7 is connected with a sensing optical fiber 8 to obtain a Brillouin backscattering optical signal and a Rayleigh backscattering optical signal in the optical fiber, and the backscattering optical signal is output through the c end of the first optical circulator 7; the output end c of the first optical circulator 7 is connected with the input end of the second optical amplifier 9, and the backward scattered optical power is amplified; the output end of the second optical amplifier 9 is connected with the input end of the second optical filter 10, noise is filtered and then connected with the a end of the third optical coupler 13, and in the third optical coupler 13, the optical signal is divided into an optical power ratio 80: 20.
In the path a, the output end c of the third optical coupler 13 is connected with the input end of the first photodetector 14, and converts the optical signal into an electrical signal; the output end of the first photodetector 14 is connected with the input end of the low-pass filter 15, and the rayleigh back-scattered light signal is filtered and then connected with the input end A of the data acquisition and processing module 35, so as to acquire rayleigh back-scattered light intensity information.
In the path B, the output end B of the third optical coupler 13 is connected with the input end of the tunable filter 16, and the brillouin backscattering optical signal is filtered out; the output end of the tunable filter 16 is connected with the input end of the third optical amplifier 17, and the back scattering optical signal is amplified; the output end of the third optical amplifier 17 is connected with the input end of the third optical filter 18, and amplified spontaneous emission noise is filtered; the output end of the third optical filter 18 is connected to the input end a of the fourth optical coupler 19, and is divided into an optical power ratio of 50: two paths 50; the output end c of the fourth optical coupler 19 is connected with the input end of the second photoelectric detector 20, and converts the optical signal into an electric signal; the output end of the second photodetector 20 is connected to the B input end of the data acquisition processing module 35, and acquires the brillouin backscattering light intensity information. And compensating the loss of the Brillouin back scattering light intensity in the sensing optical fiber by utilizing the Rayleigh back scattering light intensity information, and demodulating the intensity information of the optical signal in the optical fiber.
In the path C, the C end of the first optical coupler 3 is connected with the input end of the scrambler 11, so that the polarization state of light becomes a random state; the output end of the scrambler 11 is connected with the a end of the second optical coupler 12, and divides the reference light into an optical power ratio of 50: two paths 50; the c end of the second optical coupler 12 and the b end of the output end of the fourth optical coupler 19 are respectively connected with the a input end and the b input end of the fifth optical coupler 21, and the detection optical signal and the reference optical signal are subjected to beat frequency; the output end of the fifth optical coupler 21 is connected with the input end of the third photoelectric detector 22, and performs photoelectric conversion on beat frequency light; the output end of the third photodetector 22 is connected with the input end a of the mixer 23 for mixing; the output end of the microwave source 24 is connected with the input end b of the mixer 23 and outputs a local oscillation signal; the output end c of the mixer 23 is connected with the first input end of the analog-to-digital conversion module 27 for analog-to-digital conversion processing; the output end of the analog-to-digital conversion module 27 is connected with the input end of the FPGA module 25; the output end c of the second optical coupler 12 is connected with the input end of the fourth photoelectric detector 26 for photoelectric conversion treatment; the output end of the fourth photoelectric detector 26 is connected with the second input end of the analog-to-digital conversion module 27 for analog-to-digital conversion processing; the output of the analog-to-digital conversion module 27 is connected to the input of the FPGA module 25. In the FPGA module 25, the reference signal and the detection signal are subjected to cross-correlation processing, and the position where the frequency shift occurs can be demodulated according to the position of the cross-correlation peak by using the characteristics of the chaotic light, so that the temperature and strain occurrence position information can be demodulated. The output end of the FPGA module 25 is connected with the C input end of the data acquisition processing module 35, and the acquisition of the frequency shift information of the Brillouin backscattering is carried out.
The Brillouin scattering intensity and Brillouin frequency shift information in the sensing optical fiber are affected by temperature and strain as follows:
；
wherein epsilon refers to strain information of the optical fiber, T refers to temperature information of the optical fiber,v B referring to the brillouin shift in the system,P B referring to the brillouin backscatter intensity in the system,P R referring to the rayleigh backscatter intensity in the system,、/>parameters of brillouin shift relative strain and temperature, respectively, ">、/>Respectively the brillouin intensity versus strain and temperature.
From the above formula, the brillouin intensity and brillouin frequency shift are linear with temperature and strain. Because the optical fiber has the condition of Brillouin backscattering intensity signal loss, the ratio of the Brillouin scattering signal intensity to the Rayleigh backscattering signal intensity is taken as the Brillouin scattering intensity in the actual measurement process. Because the frequency shift information and the intensity information of the Brillouin backscattering are both sensitive to temperature and strain, the acquired frequency shift and intensity information of the Brillouin backscattering can be utilized to simultaneously demodulate the change condition of the temperature and the strain in the optical fiber.
The specific structure of the invention needs to be described that the connection relation between the component modules adopted by the invention is definite and realizable, and besides the specific description in the embodiment, the specific connection relation can bring corresponding technical effects, and solves the technical problems of the invention on the premise of not depending on the execution of corresponding software programs.
Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present invention, and not for limiting the same; although the invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the invention.
Claims (2)
1. The Brillouin optical time domain reflection temperature and strain detection device based on chaotic external modulation is characterized in that: the Brillouin backscattering optical fiber processing system comprises a narrow-linewidth chaotic external modulation laser module, an optical fiber backscattering optical signal acquisition module, a Rayleigh backscattering optical intensity information acquisition module, a Brillouin frequency shift information, a temperature/strain position information acquisition module and a signal processing module, wherein the narrow-linewidth chaotic external modulation laser module externally modulates continuous narrow-linewidth laser signals into narrow-linewidth chaotic signals, the narrow-linewidth chaotic signals enter the optical fiber backscattering optical signal acquisition module to obtain Brillouin backscattering optical signals and Rayleigh backscattering optical signals in the optical fiber, the Rayleigh backscattering optical signals are input into the Rayleigh backscattering optical intensity information acquisition module to acquire Rayleigh backscattering optical intensity information and are transmitted to the signal processing module, the Brillouin backscattering optical intensity information is input into the Brillouin backscattering optical intensity information acquisition module to acquire the Brillouin backscattering optical intensity information and are transmitted to the signal processing module, and the Brillouin frequency shift information acquired through the Brillouin frequency shift information and the temperature/strain position information acquisition module and the temperature/strain position information acquired through cross-correlation are transmitted to the signal processing module;
the narrow-linewidth chaotic external modulation laser module comprises a narrow-linewidth laser (1), an electro-optic modulation module (2), a first optical coupler (3), a spontaneous emission source (28), a second optical circulator (29), a fourth optical filter (30), an adjustable optical attenuator (31), a third optical circulator (32), a semiconductor laser (33) and a fifth photoelectric detector (34), wherein the output end of the spontaneous emission source (28) is connected with the a end of the second optical circulator (29), the fourth optical filter (30) is connected with the b end of the second optical circulator (29), the c end of the second optical circulator (29) is connected with the a end of the third optical circulator (32) through an adjustable optical attenuator (31), the c end of the third optical circulator (32) is connected with the electro-optic modulation module (2) through the fifth photoelectric detector (34), a continuous optical signal output by the narrow-linewidth laser (1) is modulated at the b end of the second optical circulator (29), the c end of the second optical circulator (29) is connected with the optical fiber chaotic external modulation module, the optical fiber is subjected to optical signal acquisition, and the optical fiber acquisition optical fiber position information is carried out by the optical fiber acquisition optical fiber position chaotic information acquisition module, and the optical fiber position acquisition optical fiber acquisition optical fiber position information acquisition module is respectively;
the optical fiber back scattering optical signal acquisition module comprises a pulse optical modulation module (4), a first optical amplifier (5), a first optical filter (6), a first optical circulator (7), a sensing optical fiber (8), a second optical amplifier (9), a second optical filter (10), a scrambler (11), a second optical coupler (12) and a third optical coupler (13), wherein the b end of the first optical coupler (3) outputs a first path of optical signal as detection light to sequentially pass through the pulse optical modulation module (4), the first optical amplifier (5) and the first optical filter (6) to be input into the a end of the first optical circulator (7), the b end of the first optical circulator (7) is connected with the sensing optical fiber (8), the Brillouin backward scattering optical signal and the Rayleigh backward scattering optical signal in the optical fiber are obtained, the backward scattering optical signal is output by the c end of the first optical circulator (7) and then is transmitted to the a end of the third optical coupler (13) through the second optical amplifier (9) and the second optical filter (10), the light output by the third optical coupler (13) is divided into two paths, the two paths are respectively input into the Rayleigh backward scattering light intensity information acquisition module, the Brillouin frequency shift information and the temperature/strain position information acquisition module, the second path optical signal output by the c end of the first optical coupler (3) is used as reference light to be input into the a end of the second optical coupler (12) through the scrambler (11), the output light of the second optical coupler (12) is divided into two paths, and the two paths are input into the Brillouin frequency shift information and temperature/strain position information acquisition module;
the Brillouin backward scattering light intensity information acquisition module comprises a tunable filter (16), a third optical amplifier (17), a third optical filter (18), a fourth optical coupler (19) and a second photoelectric detector (20), wherein a second path of light output by the b end of the third optical coupler (13) is filtered out by the tunable filter (16) and then is input into the a end of the fourth optical coupler (19) through the third optical amplifier (17) and the third optical filter (18), the fourth optical coupler (19) divides light into two paths, and a first path of light output by the c end of the fourth optical coupler (19) is input into the signal processing module through the second photoelectric detector (20) to acquire Brillouin backward scattering light intensity information;
the brillouin frequency shift information and temperature/strain position information acquisition module comprises a fifth optical coupler (21), a third photoelectric detector (22), a mixer (23), a microwave source (24) and a fourth photoelectric detector (26), wherein the output light of the second optical coupler (12) is divided into two paths, the first path of light output by the c end of the second optical coupler (12) and the second path of light output by the b end of the fourth optical coupler (19) are respectively input into the a end and the b end of the fifth optical coupler (21) for beat frequency treatment, the light output by the c end of the fifth optical coupler (21) is input into the a end of the mixer (23) through the third photoelectric detector (22), the b end of the mixer (23) is connected with the microwave source (24), the signal output by the third photoelectric detector (22) and the signal output by the microwave source (24) are subjected to frequency shift in the mixer (23), and the c end of the mixer (23) is connected with the first input end of the analog-digital conversion module (27); the second path of light output by the b end of the second optical coupler (12) is input into the signal processing module through a fourth photoelectric detector (26);
the signal processing module comprises an FPGA module (25), an analog-to-digital conversion module (27) and a data acquisition processing module (35), wherein the input end of the analog-to-digital conversion module (27) is respectively connected with the C end of the mixer (23) and the output end of the fourth photoelectric detector (26), the output end of the analog-to-digital conversion module (27) is connected with the FPGA module (25), the FPGA module (25) is subjected to chaotic cross-correlation processing, temperature/strain position information is demodulated based on a cross-correlation peak, the data acquisition processing module (35) is connected with the C end, the data acquisition processing module (35) is subjected to demodulation of Brillouin frequency shift information, the A end of the data acquisition processing module (35) is connected with the output end of the low-pass filter (15), and the B end of the data acquisition processing module (35) is connected with the output end of the second photoelectric detector (20).
2. The device for detecting the temperature and strain of brillouin optical time domain reflection by chaotic external modulation according to claim 1, wherein the device is characterized in that: the Rayleigh back scattering light intensity information acquisition module comprises a first photoelectric detector (14) and a low-pass filter (15), and a first path of light output by the c end of the third optical coupler (13) is input to the input end of the first photoelectric detector (14); the output end of the first photoelectric detector (14) is connected with the input end of the low-pass filter (15), and the rayleigh back-scattered light signals are filtered out and then input into the signal processing module for collecting rayleigh back-scattered light intensity information.
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Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7526149B1 (en) * | 2008-07-21 | 2009-04-28 | Qorex, Llc | Dual wavelength strain-temperature Brillouin sensing system and method |
| EP3232165A1 (en) * | 2016-04-15 | 2017-10-18 | Viavi Solutions Inc. | Brillouin and rayleigh distributed sensor |
| CN107941254A (en) * | 2017-11-22 | 2018-04-20 | 朱秋华 | A kind of fiber grating sensing system and its demodulation method |
| CN108180853A (en) * | 2017-12-22 | 2018-06-19 | 太原理工大学 | A kind of Brillouin light Time Domain Reflectometry strain-Sensing device based on chaotic modulation |
| CN109556659A (en) * | 2018-12-21 | 2019-04-02 | 闽南师范大学 | A kind of method and device thereof of single-ended detection Brillouin's dynamic raster sensing |
| CN110617854A (en) * | 2019-10-25 | 2019-12-27 | 华北电力大学（保定） | High-order phase modulation Rayleigh BOTDA temperature/strain measurement method and device |
| CN111141414A (en) * | 2019-12-27 | 2020-05-12 | 太原理工大学 | Temperature and strain simultaneous measurement device and method based on chaos BOCDA |
| CN112033568A (en) * | 2020-08-07 | 2020-12-04 | 太原理工大学 | Temperature and strain optical fiber sensing system adopting double-pulse modulation |
| CN113091783A (en) * | 2021-04-29 | 2021-07-09 | 太原理工大学 | High-sensitivity sensing device and method based on two-stage Brillouin scattering |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2011050136A1 (en) * | 2009-10-21 | 2011-04-28 | Redfern Integrated Optics, Inc. | System and method for using coherently locked optical oscillator with brillouin frequency offset for fiber-optics-based applications |
| US9983094B2 (en) * | 2016-09-09 | 2018-05-29 | Viavi Solutions Inc. | Temperature or strain distribution sensor comprising a coherent receiver to determine a temperature or a strain associated with a device under test |
-
2022
- 2022-01-19 CN CN202210060323.4A patent/CN114526684B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7526149B1 (en) * | 2008-07-21 | 2009-04-28 | Qorex, Llc | Dual wavelength strain-temperature Brillouin sensing system and method |
| EP3232165A1 (en) * | 2016-04-15 | 2017-10-18 | Viavi Solutions Inc. | Brillouin and rayleigh distributed sensor |
| CN107941254A (en) * | 2017-11-22 | 2018-04-20 | 朱秋华 | A kind of fiber grating sensing system and its demodulation method |
| CN108180853A (en) * | 2017-12-22 | 2018-06-19 | 太原理工大学 | A kind of Brillouin light Time Domain Reflectometry strain-Sensing device based on chaotic modulation |
| CN109556659A (en) * | 2018-12-21 | 2019-04-02 | 闽南师范大学 | A kind of method and device thereof of single-ended detection Brillouin's dynamic raster sensing |
| CN110617854A (en) * | 2019-10-25 | 2019-12-27 | 华北电力大学（保定） | High-order phase modulation Rayleigh BOTDA temperature/strain measurement method and device |
| CN111141414A (en) * | 2019-12-27 | 2020-05-12 | 太原理工大学 | Temperature and strain simultaneous measurement device and method based on chaos BOCDA |
| CN112033568A (en) * | 2020-08-07 | 2020-12-04 | 太原理工大学 | Temperature and strain optical fiber sensing system adopting double-pulse modulation |
| CN113091783A (en) * | 2021-04-29 | 2021-07-09 | 太原理工大学 | High-sensitivity sensing device and method based on two-stage Brillouin scattering |
Non-Patent Citations (1)
| Title |
|---|
| 微波电光调制的布里渊散射分布式光纤传感技术;宋牟平;光学学报(08);全文 * |
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