CN102829812B - Brillouin optical time domain analysis meter capable of locking frequencies of two lasers based on optical phase-locked loop - Google Patents
Brillouin optical time domain analysis meter capable of locking frequencies of two lasers based on optical phase-locked loop Download PDFInfo
- Publication number
- CN102829812B CN102829812B CN201210299485.XA CN201210299485A CN102829812B CN 102829812 B CN102829812 B CN 102829812B CN 201210299485 A CN201210299485 A CN 201210299485A CN 102829812 B CN102829812 B CN 102829812B
- Authority
- CN
- China
- Prior art keywords
- optical
- frequency
- communicated
- phase
- laser
- 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
Landscapes
- Optical Communication System (AREA)
Abstract
The invention discloses a Brillouin optical time domain analysis meter capable of locking frequencies of two lasers based on an optical phase-locked loop, relates to a Brillouin optical time domain analysis meter, and solves the problems of high price, complicated structure and large volume of the conventional device for detecting a beat frequency signal obtained after frequency mixing of the two lasers by utilizing a microwave frequency counter, and slow frequency scanning speed and narrow frequency scanning range caused by slow response speed of an optical delay line due to frequency locking and scanning between two distributed feedback type semiconductor lasers through the optical delay line. The Brillouin optical time domain analysis meter comprises a 1# laser, a 2# laser, a 1# optical fiber coupler, a 2# optical fiber coupler, a 3# optical fiber coupler, a phase-locked loop module, an electro-optical modulator, a pulse generator, a scrambler, a detection amplification module, an optical attenuator, an erbium doped fiber amplifier, a circulator, a photoelectric detector and a data acquisition module. The invention is suitable for the Brillouin optical time domain analysis meter.
Description
Technical field
The present invention relates to Brillouin optical time domain analysis instrument.
Background technology
Continuous distribution formula Brillouin fiber optic sensing instrument utilizes Brillouin scattering in optical fiber as sensor mechanism, can provide the high resolving power in distributed extra long distance, high-precision strain and temperature monitoring.This sensor-based system adopts the optical communication fiber of standard as sensor information, not only may be used for the monitoring of temperature and strain but also can communicate, can realize sensing with communicate multiplexing.Continuous distribution formula Brillouin fiber optic temperature and strain sensing instrument application comprises: the temperature of oil and gas pipeline and storage tank and deformation monitoring, the temperature of seabed or land high-tension cable and strain monitoring, the distributed monitoring of geologic hazard (such as landslide, rubble flow etc.), the monitoring structural health conditions of the buildings such as bridge, dam and tunnel, and fire alarm etc.
Brillouin optical time domain analysis instrument is a kind of version realizing continuous distribution formula Brillouin fiber optic temperature and strain sensing instrument, and it is paid close attention to widely because the advantage having that signal to noise ratio (S/N ratio) is high, spatial resolution is high, measuring accuracy is high and measuring distance is long obtains and study.Comprise two light sources inside Brillouin optical time domain analysis instrument to provide pump light and detection light, its gordian technique is
How to obtain two light sources that difference on the frequency is stable.At present, a kind of scheme is had to use a laser instrument to provide light source, it adopts the way of microwave modulation to obtain the detection light (M.Nikles that another relative pump light has stable frequency displacement, L.Thevenaz, and P.A.Robert, " Simple distributed fiber sensor based on Brillouin gain spectrum analysis; " Optics Letters, 21,758-760,, but this technology needs to use expensive and baroque frequency to be microwave signal generator and the high-speed electro-optic modulator of about tens GHz 1996).Another kind of scheme is that employing two laser instruments provide light source, by obtaining the stable pump light of difference on the frequency and detection light to the difference on the frequency locking of two laser instruments.Beat signal after the people such as A.W.Brown adopt microwave frequence counter to detect two laser instrument mixing and by FEEDBACK CONTROL wherein laser instrument realize the stable (A.W.Brown of difference on the frequency between two laser instruments, J.P.Smith, and X.Bao, " Brillouin scattering based distributed sensors for structural applications; " J.Intell.Mater.Syst.Struct.10,340-349,, but the price of microwave frequence counter is higher, complex structure, volume are larger 1999.).US Patent No. 7,499,151B2 propose the external optical time delay line of employing one to realize two distributed feedback (DFB) semiconductor lasers between Frequency Locking and scanning, but the shortcoming of this technology is because the response speed of optical time delay line is slow, reference time delay is little, such that frequency-scan speed is comparatively slow and frequency sweeping ranges is narrow.
Summary of the invention
The object of the invention is to solve that the price that existing employing microwave frequence counter detects the device of the beat signal after two laser instrument mixing is high, complex structure, volume are larger, adopt optical time delay line to realize two distributed feedback type semiconductor lasers between Frequency Locking and the slow and problem that frequency sweeping ranges is narrow of the frequency-scan speed that causes slowly of the response speed that scans the optical time delay line produced, a kind of Brillouin optical time domain analysis instrument locking two laser frequency based on optical phase-locked loop is provided.
The Brillouin optical time domain analysis instrument of two laser frequency is locked based on optical phase-locked loop, it is by a laser instrument, No. two laser instruments, a fiber coupler, No. two fiber couplers, No. three fiber couplers, phase-locked loop module, electrooptic modulator, pulse producer, scrambler, detection amplification module, optical attenuator, Erbium-Doped Fiber Amplifier (EDFA), circulator, photodetector and data acquisition module composition, the output terminal of a laser instrument is communicated with the optical signal input of a fiber coupler, the light signal output end of a fiber coupler is communicated with the optical signal input of electrooptic modulator with No. three fiber couplers simultaneously, the output terminal of No. two laser instruments is communicated with the optical signal input of No. two fiber couplers, the light signal output end of No. two fiber couplers is communicated with the optical signal input of optical attenuator with No. three fiber couplers simultaneously, the light signal output end of optical attenuator is communicated with one end of testing fiber, the light signal output end of No. three fiber couplers is communicated with the optical signal input of detection amplification module, the detection electrical signal of amplification module is communicated with the electric signal input end of phase-locked loop module, the control signal output terminal of phase-locked loop module is communicated with the Injection Current control end of No. two laser instruments, the pulse signal output end of pulse producer is communicated with the pulse signal input terminal of electrooptic modulator, the light signal output end of electrooptic modulator is communicated with the optical signal input of scrambler, the light signal output end of scrambler is communicated with the optical signal input of Erbium-Doped Fiber Amplifier (EDFA), circulator comprises a light signal port, No. two light signal ports and No. three light signal ports, the light signal output end of Erbium-Doped Fiber Amplifier (EDFA) is communicated with circulator light signal port, No. three light signal ports of circulator are communicated with the optical signal input of photodetector, No. two light signal ports of circulator are communicated with the other end of testing fiber, the electrical signal of photodetector is communicated with the Information Monitoring input end of data acquisition module,
Phase-locked loop module is made up of directional coupler, frequency divider, phase/frequency Discr., derived reference signal, loop filter and frequency counting unit, the electric signal input end of directional coupler is the electric signal input end of phase-locked loop module, the output terminal of a signal of directional coupler is communicated with the input end of the signal of frequency divider, and the output terminal of another signal of directional coupler is communicated with the input end of frequency counting unit; The output terminal of the signal of frequency divider is communicated with a signal input part of phase/frequency Discr., the signal output part of derived reference signal is communicated with another signal input part of phase/frequency Discr., the signal output part of phase/frequency Discr. is communicated with the signal input part of loop filter, the signal output part of loop filter is the control signal output terminal of phase-locked loop module, and the sweep limit of phase/frequency Discr. is 8 ~ 12GHz.
The present invention, owing to not comprising microwave frequence counter, achieves that Brillouin optical time domain analysis instrument price is low, structure is simple, volume is little; Optical phase-locked loop of the present invention to provide between two laser instruments accurately, fast, difference on the frequency locking and scanning on a large scale, and then obtain quick and high-precision measurement; Use frequency splitting technology that the signal after mixing is dropped to tens to hundreds of MHz from tens GHz in optical phase-locked loop, thus the device compared with low frequency and derived reference signal can be used, significantly reduce cost, simplify system.
Accompanying drawing explanation
Fig. 1 is composition structural representation of the present invention, Fig. 2 is the structural representation of the phase-locked loop module of embodiment two, Fig. 3 is the difference on the frequency schematic diagram that the employing PHASE-LOCKED LOOP PLL TECHNIQUE of embodiment two locks two external-cavity semiconductor laser, within figure the 10th minute, opens phaselocked loop.
Embodiment
Embodiment one: composition graphs 1 illustrates present embodiment, locks the Brillouin optical time domain analysis instrument of two laser frequency based on optical phase-locked loop described in present embodiment, it is by a laser instrument 1-1, No. two laser instrument 1-2, a fiber coupler 2-1, No. two fiber coupler 2-2, No. three fiber coupler 2-3, phase-locked loop module 3, electrooptic modulator 4, pulse producer 5, scrambler 6, detection amplification module 7, optical attenuator 8, Erbium-Doped Fiber Amplifier (EDFA) 9, circulator 10, photodetector 11 and data acquisition module 12 form, the output terminal of a laser instrument 1-1 is communicated with the optical signal input of a fiber coupler 2-1, the light signal output end of a fiber coupler 2-1 is communicated with the optical signal input of electrooptic modulator 4 with No. three fiber coupler 2-3 simultaneously, the output terminal of No. two laser instrument 1-2 is communicated with the optical signal input of No. two fiber coupler 2-2, the light signal output end of No. two fiber coupler 2-2 is communicated with the optical signal input of optical attenuator 8 with No. three fiber coupler 2-3 simultaneously, and the light signal output end of optical attenuator 8 is communicated with one end of testing fiber, the light signal output end of No. three fiber coupler 2-3 is communicated with the optical signal input of detection amplification module 7, the electrical signal of detection amplification module 7 is communicated with the electric signal input end of phase-locked loop module 3, the control signal output terminal of phase-locked loop module 3 is communicated with the Injection Current control end of No. two laser instrument 1-2, the pulse signal output end of pulse producer 5 is communicated with the pulse signal input terminal of electrooptic modulator 4, the light signal output end of electrooptic modulator 4 is communicated with the optical signal input of scrambler 6
The light signal output end of scrambler 6 is communicated with the optical signal input of Erbium-Doped Fiber Amplifier (EDFA) 9, circulator 10 comprises a light signal port 10-1, No. two light signal port 10-2 and No. three light signal port 10-3, the light signal output end of Erbium-Doped Fiber Amplifier (EDFA) 9 is communicated with a light signal port 10-1 of circulator 10, No. three light signal port 10-3 of circulator 10 are communicated with the optical signal input of photodetector 11, and No. two light signal port 10-2 of circulator 10 are communicated with the other end of testing fiber; The electrical signal of photodetector 11 is communicated with the Information Monitoring input end of data acquisition module 12.
The present invention is not owing to comprising microwave frequence counter, and the price achieving Brillouin optical time domain analysis instrument is low, structure is simple, volume is little; Optical phase-locked loop of the present invention to provide between two laser instruments accurately, fast, difference on the frequency locking and scanning on a large scale, and then obtain quick and high-precision measurement; Use frequency splitting technology that the signal after mixing is dropped to tens to hundreds of MHz from tens GHz in optical phase-locked loop, thus the device compared with low frequency and derived reference signal can be used, significantly reduce cost, simplify system.
The present invention adopts a laser instrument 1-1 and No. two laser instrument 1-2 two laser instruments, pump light is provided by a laser instrument 1-1, detection light is provided by No. two laser instrument 1-2, described laser instrument can be single mode narrow linewidth fiber laser, distributed feedback type semiconductor laser (DFB) and external cavity semiconductor laser (ECL), output power is 10 ~ 50mW, and wavelength is near 1550nm.By a fiber coupler 2-1 and No. two fiber coupler 2-2, No. three fiber coupler 2-3 that the laser that a laser instrument 1-1 and No. two laser instrument 1-2 exports extracts a part (5% ~ 20%) injection 50:50 are respectively carried out mixing, and convert beat signal to by detection amplification module 7.The beat signal that phase-locked loop module exports after detecting two laser instrument mixing, then provides an error signal and carrys out the frequency of regulation output light as the Injection Current control port that feedback is loaded into a wherein laser instrument thus realize the difference on the frequency of locking two laser instruments.
Embodiment two: composition graphs 2 and Fig. 3 illustrate present embodiment, present embodiment is the further restriction to the Brillouin optical time domain analysis instrument locking two laser frequency described in embodiment one based on optical phase-locked loop, phase-locked loop module 3 is by directional coupler 3-1, frequency divider 3-2, phase/frequency Discr. 3-3, derived reference signal 3-4, loop filter 3-5 and frequency counting unit 3-6 forms, the electric signal input end of directional coupler 3-1 is the electric signal input end of phase-locked loop module 3, the output terminal of a signal of directional coupler 3-1 is communicated with the input end of the signal of frequency divider 3-2, the output terminal of another signal of directional coupler 3-1 is communicated with the input end of frequency counting unit 3-6, the output terminal of the signal of frequency divider 3-2 is communicated with a signal input part of phase/frequency Discr. 3-3, the signal output part of derived reference signal 3-4 is communicated with another signal input part of phase/frequency Discr. 3-3, the signal output part of phase/frequency Discr. 3-3 is communicated with the signal input part of loop filter 3-5, and the signal output part of loop filter 3-5 is the control signal output terminal of phase-locked loop module 3.
Directional coupler 3-1 beat signal a part coupling power out for the difference on the frequency of Real-Time Monitoring two laser instruments, another part signal connects frequency divider, the function of frequency divider carries out frequency reducing to beat signal, and its output frequency equals the frequency dividing ratio N of frequency divided by frequency divider of beat signal.Phase/frequency Discr. by compare frequency divider export signal and reference signal after provide an error signal, error signal is by being loaded into the Injection Current control port of a wherein laser instrument after a loop filter, after loop-locking, the frequency of output signal of frequency divider just equals the frequency f of reference signal
r, the difference on the frequency between two laser instruments equals N × f
r.Frequency due to beat signal is approximately tens GHz, larger to its direct intractability, by signal frequency being dropped to hundreds of MHz after frequency divider, so just can use the device of lower low frequency to process, and, the frequency of derived reference signal also greatly reduces, and drop to tens to hundreds of MHz from tens GHz and make cost reduction, structure simplification, this is an innovation of this patent.Phase/frequency Discr. has response faster and wider bandwidth, and therefore can realize quick lock in and the large area scanning of difference on the frequency between two laser instruments, general sweep limit is 8 ~ 12GHz.Figure 3 shows that the difference on the frequency adopting PHASE-LOCKED LOOP PLL TECHNIQUE to lock two external-cavity semiconductor laser, within the 10th minute, open phaselocked loop.
In two laser instruments of Frequency Locking, wherein a laser instrument provides continuous print to detect light, and obtains required power by optical attenuator, then connects one end of sensor fibre.Another laser instrument obtains pumping pulse light by pulse producer and electrooptic modulator, the polarization state of pumping pulse is changed at random by scrambler, by Erbium-Doped Fiber Amplifier (EDFA), pumping pulse is amplified to required power, then is connected to the other end of sensor fibre by circulator.Continuous probe light is by entering photodetector through circulator after sensor fibre, and the signal that photodetector exports is collected by data collecting card.Described scrambler changes the polarization state of pumping pulse at random, and does multiple averaging to the signal collected and can eliminate polarization state in single-mode fiber and change the signal fluctuation caused.
Embodiment three: present embodiment is the further restriction to the Brillouin optical time domain analysis instrument locking two laser frequency described in embodiment one based on optical phase-locked loop, a laser instrument 1-1 and No. two laser instrument 1-2 all adopts single mode narrow linewidth fiber laser, distributed feedback type semiconductor laser or external cavity semiconductor laser.
Embodiment four: present embodiment is the further restriction to the Brillouin optical time domain analysis instrument locking two laser frequency described in embodiment one based on optical phase-locked loop, a fiber coupler 2-1 is identical with the value of the coupling ratio of No. two fiber coupler 2-2, and the value scope of described coupling ratio is between 95:5 and 80:20.
Embodiment five: present embodiment is the further restriction to the Brillouin optical time domain analysis instrument locking two laser frequency described in embodiment one based on optical phase-locked loop, a laser instrument 1-1 and No. two laser instrument 1-2 all adopts polarization maintaining optical fibre to export.
Embodiment six: present embodiment is the further restriction to the Brillouin optical time domain analysis instrument locking two laser frequency described in embodiment one based on optical phase-locked loop, fiber coupler 2-1, No. two fiber coupler 2-2 and No. three fiber coupler 2-3 all adopt the fiber coupler of polarization maintaining optical fibre type.
Embodiment seven: present embodiment is the further restriction to the Brillouin optical time domain analysis instrument locking two laser frequency described in embodiment one based on optical phase-locked loop, the frequency dividing ratio N of frequency divider 3-2 is: 8≤N≤200, and the range of signal after the mixing of the corresponding frequency dividing ratio N of 10GHz signal is: 1.25GHz to 100MHz.
Embodiment eight: present embodiment is the further restriction to the Brillouin optical time domain analysis instrument locking two laser frequency described in embodiment one based on optical phase-locked loop, between a laser instrument 1-1 and No. two laser instrument 1-2, the lock-in range of difference on the frequency is 8 ~ 12GHz.
Claims (7)
1. lock the Brillouin optical time domain analysis instrument of two laser frequency based on optical phase-locked loop, it is by a laser instrument (1-1), No. two laser instruments (1-2), a fiber coupler (2-1), No. two fiber couplers (2-2), No. three fiber couplers (2-3), phase-locked loop module (3), electrooptic modulator (4), pulse producer (5), scrambler (6), detection amplification module (7), optical attenuator (8), Erbium-Doped Fiber Amplifier (EDFA) (9), circulator (10), photodetector (11) and data acquisition module (12) composition, the output terminal of a laser instrument (1-1) is communicated with the optical signal input of a fiber coupler (2-1), the light signal output end of a fiber coupler (2-1) is communicated with the optical signal input of electrooptic modulator (4) with No. three fiber couplers (2-3) simultaneously, the output terminal of No. two laser instruments (1-2) is communicated with the optical signal input of No. two fiber couplers (2-2), the light signal output end of No. two fiber couplers (2-2) is communicated with the optical signal input of optical attenuator (8) with No. three fiber couplers (2-3) simultaneously, the light signal output end of optical attenuator (8) is communicated with one end of testing fiber, the light signal output end of No. three fiber couplers (2-3) is communicated with the optical signal input of detection amplification module (7), the electrical signal of detection amplification module (7) is communicated with the electric signal input end of phase-locked loop module (3), the control signal output terminal of phase-locked loop module (3) is communicated with the Injection Current control end of No. two laser instruments (1-2), the pulse signal output end of pulse producer (5) is communicated with the pulse signal input terminal of electrooptic modulator (4), the light signal output end of electrooptic modulator (4) is communicated with the optical signal input of scrambler (6), the light signal output end of scrambler (6) is communicated with the optical signal input of Erbium-Doped Fiber Amplifier (EDFA) (9), circulator (10) comprises a light signal port (10-1), No. two light signal ports (10-2) and No. three light signal ports (10-3), the light signal output end of Erbium-Doped Fiber Amplifier (EDFA) (9) is communicated with a light signal port (10-1) of circulator (10), No. three light signal ports (10-3) of circulator (10) are communicated with the optical signal input of photodetector (11), No. two light signal ports (10-2) of circulator (10) are communicated with the other end of testing fiber, the electrical signal of photodetector (11) is communicated with the Information Monitoring input end of data acquisition module (12),
It is characterized in that, phase-locked loop module (3) is by directional coupler (3-1), frequency divider (3-2), phase/frequency Discr. (3-3), derived reference signal (3-4), loop filter (3-5) and frequency counting unit (3-6) composition, the electric signal input end of directional coupler (3-1) is the electric signal input end of phase-locked loop module (3), the output terminal of a signal of directional coupler (3-1) is communicated with the input end of the signal of frequency divider (3-2), the output terminal of another signal of directional coupler (3-1) is communicated with the input end of frequency counting unit (3-6), the output terminal of the signal of frequency divider (3-2) is communicated with a signal input part of phase/frequency Discr. (3-3), the signal output part of derived reference signal (3-4) is communicated with another signal input part of phase/frequency Discr. (3-3), the signal output part of phase/frequency Discr. (3-3) is communicated with the signal input part of loop filter (3-5), the signal output part of loop filter (3-5) is the control signal output terminal of phase-locked loop module (3), and the sweep limit of phase/frequency Discr. (3-3) is 8 ~ 12GHz.
2. the Brillouin optical time domain analysis instrument of two laser frequency is locked according to claim 1 based on optical phase-locked loop, it is characterized in that, a laser instrument (1-1) and No. two laser instruments (1-2) all adopt single mode narrow linewidth fiber laser, distributed feedback type semiconductor laser or external cavity semiconductor laser.
3. the Brillouin optical time domain analysis instrument of two laser frequency is locked according to claim 1 based on optical phase-locked loop, it is characterized in that, a fiber coupler (2-1) is identical with the value of the coupling ratio of No. two fiber couplers (2-2), and the value scope of described coupling ratio is between 95:5 and 80:20.
4. lock the Brillouin optical time domain analysis instrument of two laser frequency according to claim 1 based on optical phase-locked loop, it is characterized in that, a laser instrument (1-1) and No. two laser instruments (1-2) all adopt polarization maintaining optical fibre to export.
5. the Brillouin optical time domain analysis instrument of two laser frequency is locked according to claim 1 based on optical phase-locked loop, it is characterized in that, a fiber coupler (2-1), No. two fiber couplers (2-2) and No. three fiber couplers (2-3) all adopt the fiber coupler of polarization maintaining optical fibre type.
6. the Brillouin optical time domain analysis instrument of two laser frequency is locked according to claim 1 based on optical phase-locked loop, it is characterized in that, the frequency dividing ratio N of frequency divider (3-2) is: 8≤N≤200, and the range of signal after the mixing of the corresponding frequency dividing ratio N of 10GHz signal is: 1.25GHz to 100MHz.
7. the Brillouin optical time domain analysis instrument of two laser frequency is locked according to claim 1 based on optical phase-locked loop, it is characterized in that, between a laser instrument (1-1) and No. two laser instruments (1-2), the lock-in range of difference on the frequency is 8 ~ 12GHz.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210299485.XA CN102829812B (en) | 2012-08-22 | 2012-08-22 | Brillouin optical time domain analysis meter capable of locking frequencies of two lasers based on optical phase-locked loop |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210299485.XA CN102829812B (en) | 2012-08-22 | 2012-08-22 | Brillouin optical time domain analysis meter capable of locking frequencies of two lasers based on optical phase-locked loop |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102829812A CN102829812A (en) | 2012-12-19 |
| CN102829812B true CN102829812B (en) | 2015-01-07 |
Family
ID=47333029
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201210299485.XA Active CN102829812B (en) | 2012-08-22 | 2012-08-22 | Brillouin optical time domain analysis meter capable of locking frequencies of two lasers based on optical phase-locked loop |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102829812B (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103344614B (en) * | 2013-07-02 | 2015-09-23 | 中国科学院合肥物质科学研究院 | A kind of atmospheric transmissivity at high precision measurement mechanism and measuring method |
| CN103727969B (en) * | 2014-01-10 | 2016-08-17 | 电子科技大学 | Based on delay pulse Raman amplifiction distributed sensing system |
| CN105092141B (en) * | 2015-07-22 | 2018-09-07 | 哈尔滨工业大学 | Highly sensitive distributed hydrostatic pressure method for sensing |
| CN105241482B (en) * | 2015-10-14 | 2018-02-23 | 中国船舶重工集团公司第七一五研究所 | A kind of Active Optical Fiber grating sensor Wavelength demodulation system and method |
| CN107044862B (en) * | 2017-01-20 | 2023-09-05 | 石家庄铁道大学 | Hybrid fiber optic sensing system |
| CN110412538B (en) * | 2019-01-29 | 2021-06-04 | 苏州溯光科技信息有限公司 | Linear frequency-sweeping laser source and laser radar |
| CN109959627B (en) * | 2019-04-10 | 2021-07-06 | 哈尔滨工业大学 | Rapid gas absorption spectrum measuring device and method based on optical frequency agility |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5574588A (en) * | 1994-02-23 | 1996-11-12 | Nippon Telegraph And Telephone Corporation | Phase lock loop circuit using optical correlation detection |
| CN101800395A (en) * | 2010-03-04 | 2010-08-11 | 浙江大学 | Digitalized laser phase-locking device and phase-locking method |
| CN101929880A (en) * | 2010-08-09 | 2010-12-29 | 宁波诺驰光电科技发展有限公司 | Novel Brillouin optical time domain analyzer |
| CN102128639A (en) * | 2010-12-24 | 2011-07-20 | 中国计量学院 | Spontaneous Brillouin scattered light time-domain reflectometer on basis of double laser frequency locking |
-
2012
- 2012-08-22 CN CN201210299485.XA patent/CN102829812B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5574588A (en) * | 1994-02-23 | 1996-11-12 | Nippon Telegraph And Telephone Corporation | Phase lock loop circuit using optical correlation detection |
| CN101800395A (en) * | 2010-03-04 | 2010-08-11 | 浙江大学 | Digitalized laser phase-locking device and phase-locking method |
| CN101929880A (en) * | 2010-08-09 | 2010-12-29 | 宁波诺驰光电科技发展有限公司 | Novel Brillouin optical time domain analyzer |
| CN102128639A (en) * | 2010-12-24 | 2011-07-20 | 中国计量学院 | Spontaneous Brillouin scattered light time-domain reflectometer on basis of double laser frequency locking |
Also Published As
| Publication number | Publication date |
|---|---|
| CN102829812A (en) | 2012-12-19 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102829812B (en) | Brillouin optical time domain analysis meter capable of locking frequencies of two lasers based on optical phase-locked loop | |
| CN102620857B (en) | Brillouin optical time domain reflectometer for single-photon detection based on edged filter method | |
| CN102829806B (en) | Optical fiber sensing system based on phase-shifted optical fiber grating | |
| CN102759371B (en) | COTDR (coherent detection based optical time-domain reflectometry) fused long-distance coherent detection brilouin optical time-domain analyzer | |
| CN102809430B (en) | Device for Brillouin optical time domain reflectometer based on optical phase-locked ring | |
| CN103123285B (en) | Distributed optical fiber sensing device based on chaotic laser coherence method, and measurement method of distributed optical fiber sensing device | |
| CN102589592B (en) | Multi-wavelength light source-based Brillouin optical time domain reflectometer | |
| CN107917738A (en) | A kind of while measurement temperature, strain and the distributed optical fiber sensing system of vibration | |
| CN102384799B (en) | Frequency sweeping and data processing method based on Brillouin distributed fiber sensing system correlation detection scheme | |
| CN104677396A (en) | Dynamic distributed Brillouin optical fiber sensing device and method | |
| CN104180833A (en) | Optical time domain reflectometer simultaneously sensing temperature and stress | |
| CN108120525A (en) | Optical fiber grating temperature/strain sensing system and its demodulation method | |
| CN203310428U (en) | Distributed Brillouin optical fiber sensing system based on coherent detection | |
| CN101929880B (en) | Novel Brillouin optical time domain analyzer | |
| US10145726B2 (en) | Fiber optic acoustic wave detection system | |
| CN103674497B (en) | Narrow linewidth laser linewidth high-precision measuring system | |
| CN101949743B (en) | Novel Brillouin time domain analyzer | |
| CN103323041A (en) | Distributed Brillouin optical fiber sensing system based on coherent detection | |
| CN103604450A (en) | Seed injection BOTDR distributed optical fiber sensing system | |
| CN105180823A (en) | Fiber laser static state strain demodulation system based on frequency locking technology and beat frequency principle | |
| CN204439100U (en) | Dynamic distributed Brillouin light fiber sensing equipment | |
| CN103837165A (en) | Brillouin time-domain analysis system based on Brillouin laser and automatic heterodyne detection | |
| CN110243493A (en) | Brillouin optical time-domain reflectometer device and method based on super continuous spectrums | |
| CN103674082B (en) | A kind of High-spatial-resolutoptical optical frequency domain reflectometer system based on four-wave mixing process | |
| CN104729750A (en) | Distributed optical fiber temperature sensor based on Brillouin scattering |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |