WO2015120888A1 - Procédé et dispositif de détection distribuée optique de brillouin stimulée sans balayage et à sonde double - Google Patents

Procédé et dispositif de détection distribuée optique de brillouin stimulée sans balayage et à sonde double Download PDF

Info

Publication number
WO2015120888A1
WO2015120888A1 PCT/EP2014/052729 EP2014052729W WO2015120888A1 WO 2015120888 A1 WO2015120888 A1 WO 2015120888A1 EP 2014052729 W EP2014052729 W EP 2014052729W WO 2015120888 A1 WO2015120888 A1 WO 2015120888A1
Authority
WO
WIPO (PCT)
Prior art keywords
probe
optical
wave
brillouin
frequency
Prior art date
Application number
PCT/EP2014/052729
Other languages
English (en)
Inventor
Chin SANGHOON
Original Assignee
Omnisens Sa
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Omnisens Sa filed Critical Omnisens Sa
Priority to PCT/EP2014/052729 priority Critical patent/WO2015120888A1/fr
Publication of WO2015120888A1 publication Critical patent/WO2015120888A1/fr

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
    • G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
    • G01D5/26—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light
    • G01D5/266—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light by interferometric means
    • 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
    • G01B11/18—Measuring arrangements characterised by the use of optical techniques for measuring the deformation in a solid, e.g. optical strain gauge using photoelastic elements
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
    • G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
    • G01D5/26—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light
    • G01D5/268—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light using optical fibres
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
    • G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
    • G01D5/26—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light
    • G01D5/32—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light
    • G01D5/34—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light the beams of light being detected by photocells
    • G01D5/353—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light the beams of light being detected by photocells influencing the transmission properties of an optical fibre
    • G01D5/35338—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light the beams of light being detected by photocells influencing the transmission properties of an optical fibre using other arrangements than interferometer arrangements
    • G01D5/35354—Sensor working in reflection
    • G01D5/35358—Sensor working in reflection using backscattering to detect the measured quantity
    • G01D5/35364—Sensor working in reflection using backscattering to detect the measured quantity using inelastic backscattering to detect the measured quantity, e.g. using Brillouin or Raman backscattering
    • 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
    • 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
    • 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

Definitions

  • the invention relates to a stimulated Brillouin optical distributed sensing method which allows fast measurement rates and improved detection sensitivity.
  • the invention relates also to a device implementing the method.
  • the field of the invention is, but not limited to, distributed temperature and/or strain sensing using Brillouin scattering.
  • Brillouin scattering in optical fibers is a well-known technique for performing measurements of temperature and/or strain along long distances.
  • Brillouin scattering occurs when a light wave propagating in a medium
  • acoustic waves such as an optical fiber
  • the light wave interacts with these variations of index of refraction and a fraction of the light is scattered accordingly. Since acoustic waves propagate at the speed of sound in the medium, deflected light is also subjected to a Doppler shift, so its frequency changes.
  • the speed of sound in the medium depends on the temperature of the medium or on the strain. So, a variation of any of these parameters induces a variation of the frequency shift of the scattered light due to Brillouin scattering, and so may be measured .
  • an intense beam such as a laser beam travels in a medium such as an optical fiber
  • the variations in the electric field of the beam itself may produce acoustic vibrations in the medium.
  • the beam may undergo Brillouin scattering from these vibrations, usually in opposite direction to the incoming beam.
  • Brillouin optical time domain instruments have been done on the basis of this principle. They allow measuring the temperature and/or the strain along distributed sensors based on single-mode optical fibers which may be several kilometers long.
  • the applications relate main ly to the domains of geosciences, mining , oil exploitation, energy transportation, and civil engineering for the mon itoring of large structures.
  • BOTDA Bril louin Optical Time Domain Analyzers
  • An optical pulsed pump wave is launched into a sensing optical fiber of the d istributed sensor.
  • a continuous optical probe wave is launched into the same sensing fiber from the opposite end , so that the pump and the probe signals travel in the sensing fiber in opposite directions. So, the pump and the probe sig nals can interfere to activate electrostriction and mutually interact throug h the stimulated Bril louin scattering process (SBS) . Due to the pulsed nature of the pump, the SBS interaction between the pump and the probe takes place at different position along the fiber at different time .
  • SBS stimulated Bril louin scattering process
  • the SBS interaction results in an energy transfer between the pulsed pump wave and the probe wave.
  • the probe wave emerg ing from the sensing fiber is detected and processed so as to determine the SBS interaction and thus the variations of temperature and/or strain along the sensing fiber.
  • the Stokes spontaneous Brillouin spectrum is located at frequencies about 1 1 G Hz lower than the freq uency of the pump wave, while the anti-Stokes spontaneous Bril louin spectrum is located at frequencies about 11 G Hz higher than the freq uency of the pump wave .
  • Both Stokes and anti-Stokes Bril louin spectra have a Lorentzian shape, with the intrinsic bandwidth of about 30 MHz at full width at half maximum (FWHM).
  • the respective peak frequencies where the Brillouin gain and the Brillouin loss are the largest are usually defined as Brillouin frequencies. In standard conditions these Brillouin frequencies have a linear relationship with temperature and strain, typically of 1 MHz/K or 1 ⁇ /20 ⁇ respectively, ⁇ being the axial elongation or compression of the fiber.
  • measurements are usually done in loss mode.
  • the frequency of the probe wave is varied step-by- step across a frequency range covering the Brillouin loss spectrum.
  • a signal is acquired in the time domain whose local amplitude depends on the Brillouin interaction strength at the corresponding location along the sensing fiber.
  • the measurements at different frequencies are combined to reconstruct the shape of the Brillouin loss interaction spectrum and to compute the corresponding local Brillouin frequency.
  • the probe wave is positioned at a frequency which is shifted relative to the Brillouin frequency (in pre-defined conditions of strain and temperature) so as to fall in a region of the Brillouin gain spectrum where the variability is high, such as for instance the frequency corresponding to the half maximum of the spectrum or the -3dB frequency.
  • the Brillouin gain spectrum shifts locally in frequency with variations of temperature and/or strain, the amplitude of the probe wave varies accordingly. Under these conditions, the Brillouin frequency may be obtained directly from the amplitude of the probe wave at a single frequency around the -3dB frequency.
  • the average probe frequency is different, but close to within a half spectral width of the Stokes or the anti-Stokes Brillouin spectrum, from the pump frequency.
  • the method of the invention may further comprise steps of:
  • the pre-established relation may take into account gains and losses respectively undergone by the first and the second optical probe waves through stimulated Brillouin scattering interactions.
  • the pump generation means and the probe generation means may comprise respectively a laser source.
  • Fig. 4 shows the spectral arrangement of the pump and probe signals
  • the source coupler 12 directs also a part of the light issued from the source 11 towards a probe modulator 15 for generating a first probe wave 44 and a second probe wave 45 with respective frequencies v PR i and v PR2 located symmetrically relative to the frequency V
  • the probe modulator 15 is preferably an electro-optic modulator 15 configured so as to modulate the intensity of the incoming signal according to a Dual Side Band with Suppressed Carrier (DBS-SC) modulation scheme. It generates at its output an optical signal which comprises the two spectral components with respective frequencies v PR i and v PR2 located symmetrically relative to the frequency V
  • DBS-SC Dual Side Band with Suppressed Carrier
  • the first laser source 20 emits an optical wave with frequency v p , which is fed to a pulse generator 14 for generating the optical pulsed pump wave 41 with frequency v p .
  • a first laser source 30 is used for generating the pulsed pump signal
  • a second laser 31 is used for generating the first probe signal 44
  • a third laser source 32 is used for generating the second probe signal 45.
  • the first laser source 30 emits an optical wave with frequency v p , which is fed to a pulse generator 14 for generating an optical pulsed pump wave 41 with frequency v p .
  • the second laser source 31 and the third laser source 32 are adjusted at frequencies v PR i and v PR2 , respectively.
  • the frequencies v p , v PR i and v PR2 are adjusted to that the average frequency V
  • the light from the second laser source 31 (the first probe signal 44) and the light from the third laser source 32 (the second probe signal 45) are combined by a coupler 34 for being directed into the sensing fiber 16.
  • the principle of dynamic measurement of the invention relies on the unbalanced respective Brillouin gain and loss of the first and the second probe signals 44, 45.
  • These Brillouin gain and loss resonances 42, 43 correspond respectively to the Stokes and the anti-Stokes Brillouin spectra around the pulsed pump frequency v p .
  • the maxima 46, 47 of these gain and loss resonances 42, 43 are respectively located at the Stokes and the anti-Stokes Brillouin frequencies.
  • the difference between these Brillouin frequencies 46, 47 and the pulsed pump frequency v p corresponds to the Brillouin frequency shift v Bo -
  • the pump frequency v p is equal to the laser frequency V
  • aS er, hence v p V
  • the amount of Brillouin gain 42 that the first probe wave 44 with frequency v PRi experiences through the Stimulated Brillouin Scattering (SBS) interaction with the pump signal 41 is equivalent to the amount of Brillouin loss that the second probe wave 45 with frequency v PR2 experiences. Therefore, the net Brillouin gain for the first and the second probe signal 44, 45 remains constant while scanning the modulation frequency v m0 d in the vicinity of the Brillouin frequency v Bo of the sensing fiber 16.
  • the pulsed pump signal at v p When the pump frequency v p is different from the laser frequency V
  • both stimulated Brillouin scattering sig nals resulting from the respective interactions in the sensing fiber 16 of the first and the second probe waves 44, 45 with the optical pulsed pump wave 41 are detected simultaneously on the photodetector 19. So, we obtain a measurement sig nal the amplitude of which is representative of the net Bril louin gain (comprising the Brillouin gain 42 at freq uency v PR i and the Bril louin loss at freq uency v PR2 ).
  • Fig . 5 shows the amplitude of the net Brillouin gain 51 that the probe signals experiences in function of the modulation freq uency v m0 d, in a preferred measurement config uration as explained below.
  • the modulation freq uency v m0 d and the pump frequency v p are adjusted so that :
  • the first probe sig nal 44 with freq uency v PR i is spectrally placed at the freq uency correspond ing to the half maximum of the Brillouin gain spectrum 42 (-3d B Brillouin gain), for instance on the upper frequencies side of the Bril louin gain spectrum 42;
  • the pump freq uency v p is shifted relative to the laser freq uency V
  • the first and the second probe signal 44, 45 are spectral ly placed on the same frequencies side (the upper or the lower) of the respective Brillouin loss and gain spectra 42, 43. Under these conditions, the respective Brillouin loss and gain for the spectral lines at v PR i and v PR2 compensate perfectly, resulting in a zero net Brillouin gain .
  • the initial adjustment step is done in conditions of temperature and/or strain along the sensing fiber 16 which are considered as reference temperature and/or strain conditions.
  • the modulation frequency v m0d is adjusted in function of the Brillouin frequency shift v Bo corresponding to these reference conditions.
  • the Brillouin loss resonance shifts towards higher frequency while the Brillouin gain resonance shifts towards lower frequency.
  • the Brillouin gain for the spectral component at v PR i decreases while the Brillouin loss for the spectral component at v PR2 increases. As a result, the net Brillouin gain 51 becomes negative.
  • the net Brillouin gain 51 as measured by the detector 19 vary with respect to the shift of Brillouin gain/loss resonance, which is caused by any change of temperature and/or strain, as shown in Fig . 5.
  • the sensing system of the invention is able to measure fast variation of temperature and/or strain .
  • the system of the invention takes the advantage of push-pull effect in terms of Brillouin gain and loss
  • the system of the invention doesn't need an optical filter for filtering out the Brillouin gain or the Brillouin loss contribution, as usually done in the BOTDA systems of the prior art. So, since the optical power of the probe signal is two times higher, the SNR can be also enhanced, thus improving the measurement accuracy.
  • the system can overcome the detrimental nonlinear phenomena such as modulation instability and four-wave mixing, which may act as actual limitation in terms of measurement accuracy (SNR) and measurement distance in some methods;
  • SNR measurement accuracy
  • the SNR can be enhanced, hence improving the measurement accuracy
  • the maximum achievable sensing distance can be enhanced

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Optical Transform (AREA)

Abstract

La présente invention concerne un procédé de détection distribuée optique de Brillouin comprenant les étapes consistant à (i) fournir une onde (41) de pompe pulsée optique à une fréquence de pompe, (ii) fournir une première et une seconde onde (44, 45) de sonde optique respectivement à une première et une seconde fréquence de sonde, (iii) détecter un signal de diffusion de Brillouin stimulée obtenue des interactions respectives dans une fibre optique de détection des première et seconde ondes (44, 45) de sonde optique avec l'onde (41) de pompe pulsée optique, la première et la seconde onde (44, 45) de sonde optique étant respectivement situées spectralement à l'intérieur des spectres de Stokes et anti-Stokes Brillouin (42, 43) de l'onde (41) de pompe pulsée optique, et la fréquence de sonde moyenne correspondant à une valeur moyenne des première et seconde fréquences de sonde étant différente, mais proche d'une demie largeur spectrale du spectre de Stokes ou anti-Stokes Brillouin (42, 43) à partir de la fréquence de la pompe. L'invention concerne en outre un dispositif mettant en œuvre le procédé.
PCT/EP2014/052729 2014-02-12 2014-02-12 Procédé et dispositif de détection distribuée optique de brillouin stimulée sans balayage et à sonde double WO2015120888A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
PCT/EP2014/052729 WO2015120888A1 (fr) 2014-02-12 2014-02-12 Procédé et dispositif de détection distribuée optique de brillouin stimulée sans balayage et à sonde double

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/EP2014/052729 WO2015120888A1 (fr) 2014-02-12 2014-02-12 Procédé et dispositif de détection distribuée optique de brillouin stimulée sans balayage et à sonde double

Publications (1)

Publication Number Publication Date
WO2015120888A1 true WO2015120888A1 (fr) 2015-08-20

Family

ID=50231119

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP2014/052729 WO2015120888A1 (fr) 2014-02-12 2014-02-12 Procédé et dispositif de détection distribuée optique de brillouin stimulée sans balayage et à sonde double

Country Status (1)

Country Link
WO (1) WO2015120888A1 (fr)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109579726A (zh) * 2018-12-24 2019-04-05 南京东智安全科技有限公司 一种长标距分布式光纤布里渊传感-解调系统及应变测量方法
CN111721438A (zh) * 2020-06-08 2020-09-29 太原理工大学 一种噪声调制线阵ccd采集的免扫频botda装置
CN113532303A (zh) * 2021-07-05 2021-10-22 浙江大学 一种利用外加应变对物体应变位置测试装置和方法
WO2023248437A1 (fr) * 2022-06-23 2023-12-28 日本電信電話株式会社 Dispositif d'analyse de gain de brillouin et procédé d'analyse de gain de brillouin

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6237421B1 (en) * 1998-06-19 2001-05-29 Mitsubishi Denki Kabushiki Kaisha Apparatus for measuring a characteristic of an object using an optical fiber and light pulses
WO2012098036A2 (fr) * 2011-01-20 2012-07-26 Omnisens Sa Appareil de capteur de déformation et procédé de détection de déformation
WO2012101592A1 (fr) 2011-01-27 2012-08-02 Ramot At Tel Aviv University Ltd. Détection brillouin distribuée et dynamique dans des fibres optiques
US20130020486A1 (en) * 2010-04-13 2013-01-24 China Jiliang University Distributed optical fiber sensor based on roman and brillouin scattering
WO2013013712A1 (fr) * 2011-07-27 2013-01-31 Omnisens Sa Capteur et procédé de détection
WO2013185810A1 (fr) * 2012-06-13 2013-12-19 Omnisens Sa Système de détection et procédé de détection de diffusion de brillouin répartie

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6237421B1 (en) * 1998-06-19 2001-05-29 Mitsubishi Denki Kabushiki Kaisha Apparatus for measuring a characteristic of an object using an optical fiber and light pulses
US20130020486A1 (en) * 2010-04-13 2013-01-24 China Jiliang University Distributed optical fiber sensor based on roman and brillouin scattering
WO2012098036A2 (fr) * 2011-01-20 2012-07-26 Omnisens Sa Appareil de capteur de déformation et procédé de détection de déformation
WO2012101592A1 (fr) 2011-01-27 2012-08-02 Ramot At Tel Aviv University Ltd. Détection brillouin distribuée et dynamique dans des fibres optiques
WO2013013712A1 (fr) * 2011-07-27 2013-01-31 Omnisens Sa Capteur et procédé de détection
WO2013185810A1 (fr) * 2012-06-13 2013-12-19 Omnisens Sa Système de détection et procédé de détection de diffusion de brillouin répartie

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109579726A (zh) * 2018-12-24 2019-04-05 南京东智安全科技有限公司 一种长标距分布式光纤布里渊传感-解调系统及应变测量方法
CN109579726B (zh) * 2018-12-24 2023-03-07 南京东智安全科技有限公司 一种长标距分布式光纤布里渊传感-解调系统及应变测量方法
CN111721438A (zh) * 2020-06-08 2020-09-29 太原理工大学 一种噪声调制线阵ccd采集的免扫频botda装置
CN113532303A (zh) * 2021-07-05 2021-10-22 浙江大学 一种利用外加应变对物体应变位置测试装置和方法
WO2023248437A1 (fr) * 2022-06-23 2023-12-28 日本電信電話株式会社 Dispositif d'analyse de gain de brillouin et procédé d'analyse de gain de brillouin

Similar Documents

Publication Publication Date Title
US9804001B2 (en) Brillouin optical distributed sensing device and method with improved tolerance to sensor failure
US10048115B2 (en) Optical sensor and method of use
JP3780322B2 (ja) 分布型の歪み及び温度センシングシステム
JP6308160B2 (ja) 光ファイバ歪み測定装置及び光ファイバ歪み測定方法
JP5855693B2 (ja) 振動検出装置及び振動検出方法
US20160109222A1 (en) Hybrid raman and brillouin scattering in few-mode fibers
KR101310783B1 (ko) 브릴루앙 이득 및 손실 동시 측정을 이용한 분포형 광섬유 센서 및 센싱 방법
WO2015120888A1 (fr) Procédé et dispositif de détection distribuée optique de brillouin stimulée sans balayage et à sonde double
Huang et al. Hybrid distributed fiber-optic sensing system by using Rayleigh backscattering lightwave as probe of stimulated Brillouin scattering
WO2014177197A1 (fr) Procédé et dispositif de détection à fibre optique distribuée de diffusion brillouin stimulée par double pompage
KR101292549B1 (ko) 분포형 광섬유 센서 및 분포형 광섬유 센서의 비트 노이즈 억제 방법
Bian et al. Vibration measurement technique for repeated fiber-optic hydrophone transmission cable system
EP3100005A1 (fr) Dispositif de détection optique distribué et procédé de mesure sur des plages étendues
WO2014177198A1 (fr) Procédé et dispositif de détection à fibre optique distribuée de diffusion de brillouin stimulée par double pompage sans balayage
AU2015201357B2 (en) Optical sensor and method of use
Ishimaru et al. Fast BOTDA acquiring method based on broadband light as a probe signal
RU170943U1 (ru) Распределенный волоконно-оптический датчик
RU170925U1 (ru) Протяженный распределенный волоконно-оптический датчик
Sandah et al. Mitigation of spectral shadowing effect in direct detection double-pulse FBG-assisted phase-OTDR
Ding et al. Dynamic Linewidth Measurements of Tunable Fiber Lasers for Optical Frequency Domain Reflectometry
Iribas Pardo et al. Simplified Brillouin sensor for structural health monitoring applications based on passive optical filtering

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 14707955

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 14707955

Country of ref document: EP

Kind code of ref document: A1