CN101963516A - Polarization-sensitive distributed perturbation sensing and measuring method and system - Google Patents

Polarization-sensitive distributed perturbation sensing and measuring method and system Download PDF

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CN101963516A
CN101963516A CN201010286857.6A CN201010286857A CN101963516A CN 101963516 A CN101963516 A CN 101963516A CN 201010286857 A CN201010286857 A CN 201010286857A CN 101963516 A CN101963516 A CN 101963516A
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polarization
beam apparatus
balance
photoelectric commutator
polarization beam
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CN101963516B (en
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张旭苹
陈勐勐
王峰
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Nanjing University
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Nanjing University
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Abstract

The invention discloses a polarization-sensitive distributed perturbation sensing method and a polarization-sensitive distributed perturbation sensing system. The better embodiment of the polarization-sensitive distributed perturbation sensing system comprises a function generator (1), a pulse laser (2), a polarization controller (3), a circulator (4), a sensing optical fiber (5), a polarization beam splitter (6), a balanced amplification photoelectric converter (7), a data acquisition unit (8) and a data processing unit (9), wherein the intensity of two paths of optical signals of which the polarization directions are vertical mutually is subjected to substraction by the balanced amplification photoelectric converter so as to obtain the intensity difference reflecting the change of the polarization state of the two paths of optical signals; and data acquired by a data acquisition module is detailedly analyzed to realize the sensitive monitoring on optical perturbation signals. The method has the advantage of improving the detection sensitivity of the sensing system greatly.

Description

A kind of Polarization-Sensitive distributed perturbation sensing measuring method and system
Technical field
The present invention relates to a kind of optical fiber sensing system, relate in particular to a kind of Polarization-Sensitive distributed perturbation method for sensing and system based on polarization beam apparatus and balance amplification photoelectric commutator.
Background technology
Extraneous extruding, impact, vibration etc. all can cause the disturbance of optical fiber, and these perturbation meetings cause the variation of fiber birefringence axle and then cause the variation of the light signal polarization state of transmitting in the optical fiber.Utilize above-described polarization state variation characteristic just based on the moving optical fiber sensing system of Polarization-Sensitive distributed perturbation, come perception optical fiber whether to be subjected to external interference along the line by the polarization state of analyzing the Rayleigh scattering light signal that transmits dorsad in the optical fiber.
In the prior art, the measuring method of light signal polarization state has multiple, comprise analyzing meter method and based on the method for polarization beam apparatus and double detector, analyzing meter method is the variation of reacting polarization state through the light signal strength of analyzing meter by measuring, and the method can not make full use of the energy of tested light signal; Method based on polarization beam apparatus and double detector is to use polarization beam apparatus that tested light signal is divided into orthogonal two ways of optical signals, two ways of optical signals with polarization beam apparatus output is input to two photodetectors respectively then, gather the data of two paths of signals then respectively and do data processing respectively, though the method can make full use of the energy of light signal but need use two photodetectors because of system, structure is complicated, and data volume is big, the data processing time that needs is longer, causes the response time of system longer.Find after deliberation in addition after carrying out spectrum transformation, to cause the reason of measuring blind spot not to be because polarized light signal is zero with vertical this road light signal output intensity that causes of a polarization axle wherein based on Polarization-Sensitive distributed perturbation sensor, but because the polarization state that causes by perturbation change with change before compare very faintly, the method that therefore how to provide a kind of highly sensitive measurement polarization state to change is to optimize the problem that need solve based on Polarization-Sensitive distributed perturbation sensor-based system.
Summary of the invention
The purpose of this invention is to provide the method that a kind of highly sensitive measurement polarization state changes, and based on this method proposition a kind of Polarization-Sensitive distributed perturbation sensing measuring method and system, to overcome the deficiency of prior art scheme based on polarization beam apparatus and balance amplification photoelectric commutator.
Above-mentioned measuring method of amplifying the Polarization-Sensitive distributed perturbation optical fiber sensing system of photoelectric commutator based on polarization beam apparatus and balance of the present invention is meant the method that polarization state changes of measuring, technical scheme of the present invention is: a kind of Polarization-Sensitive distributed perturbation method for sensing, to in the sensor fibre or react optical fiber by a circulator to the polarization state measurement of the light signal of Rayleigh scattering dorsad that detectable signal produced of sensor fibre and whether be subjected to external interference along the line, at first use a polarization beam apparatus to be divided into mutually orthogonal two-way polarized light in the sensor fibre or through the tested rayleigh backscattering light signal of circulator output, then this two-way polarized light signal is imported balance respectively and amplified two input ports of photoelectric commutator, the polarization state that draws two ways of optical signals changes the poor of the light intensity that causes.Balance is amplified the output of photoelectric commutator (being the difference photo amplifier), and the polarization state that draws two ways of optical signals changes the poor of the light intensity that causes.
Device of the present invention is achieved through the following technical solutions: based on the Polarization-Sensitive distributed perturbation optical fiber sensing system of polarization beam apparatus and balance amplification photoelectric commutator, comprise: function generator 1, pulsed laser 2, Polarization Controller 3, circulator 4, sensor fibre 5, polarization beam apparatus 6, balance is amplified photoelectric commutator 7, data acquisition unit 8, data processing unit 9; Two synchronous triggering output ports of described function generator 1 connect respectively and trigger the input end of described pulsed laser 2 and the triggering input port of described data acquisition unit 8; The output terminal of described pulsed laser 2 connects the input end of described Polarization Controller 3; The output terminal of described Polarization Controller 3 connects described circulator 4 ports
Figure 337468DEST_PATH_IMAGE001
The port of described circulator 4
Figure 835446DEST_PATH_IMAGE002
Connect described sensor fibre 5; Described circulator 4 ports The input end that connects described polarization beam apparatus 6; Two output ports of described polarization beam apparatus 6 connect two input ports that balance is amplified photoelectric commutator 7; Described balance is amplified the data acquisition input port of the output port connection data acquisition unit 8 of photoelectric commutator 7; The output terminal of described data acquisition unit 8 connects the input end of data processing unit 9.
The above-mentioned tested rayleigh backscattering flashlight of sensor fibre (or passing through circulator) being exported based on the photoelectric commutator of balance amplification described in the Polarization-Sensitive distributed perturbation optical fiber sensing system of polarization beam apparatus and amplification photoelectric commutator (balance photodetector) of the present invention subtracts each other through the intensity of the two-way polarized light signal of polarization beam apparatus (PBS) beam splitting gained, and the energy difference that makes full use of the polarization signal of two-way energy complement reacts the polarization state variation that extraneous perturbation brings.
As seen from the above technical solution provided by the invention, of the present invention based on the Polarization-Sensitive distributed perturbation sensor-based system of polarization beam apparatus and balance amplification photoelectric commutator and the method that the measurement polarization state changes thereof, the polarization state of using balance amplification photoelectric commutator that the intensity of two-way quadrature input optical signal is subtracted each other and obtaining changes the intensity difference that causes, utilizes data processing unit that the signal that is obtained by data acquisition is carried out analyzing and processing again.Can realize Sensitive Detection to optical fiber perturbation signal.
The invention has the beneficial effects as follows: propose the method that a kind of highly sensitive measurement polarization state changes, and based on a kind of Polarization-Sensitive distributed perturbation sensing measurement system of this method proposition based on polarization beam apparatus and balance amplification photoelectric commutator, overcome the deficiency of prior art scheme, with compare based on the method for polarization beam apparatus and double detector, the present invention has simplified system and has saved cost; Compare with analyzing meter method, the present invention can improve 3dB with the measurable dynamic range of system, the detectable minimum energy of system can have been improved 3dB again simultaneously.
Description of drawings
Fig. 1 is an analyzing meter method schematic diagram of measuring polarization state in the prior art
Fig. 2 is the method schematic diagram based on polarization beam apparatus and double detector of measuring polarization state in the prior art
Fig. 3 is the method block diagram based on polarization beam apparatus and balance amplification photoelectric commutator of the measurement polarization state among the present invention
Fig. 4 is the structured flowchart of the optical fiber perturbation sensor-based system among the present invention.
Embodiment
Describe preferred embodiment of the present invention in detail below in conjunction with accompanying drawing.
Polarization-Sensitive distributed perturbation optical fiber sensing system based on polarization beam apparatus and balance amplification photoelectric commutator of the present invention, its preferable embodiment as shown in Figure 4, comprise function generator 1, pulsed laser 2, Polarization Controller 3, circulator 4, sensor fibre 5, polarization beam apparatus 6, balance is amplified photoelectric commutator 7, data acquisition unit 8, data processing unit 9.
Concrete implementation step when the present invention is used to monitor is as follows:
1) described function generator 1 sends two synchronous triggering signals and is respectively applied for described pulsed laser 2 of triggering and described data acquisition unit 8.
2) the direct impulse light signal of described pulsed laser 2 outputs passes through described Polarization Controller 3, described circulator 4
Figure 869316DEST_PATH_IMAGE001
,
Figure 564870DEST_PATH_IMAGE002
Port enters described sensor fibre 5.
3) light of Rayleigh scattering signal dorsad that produces in described sensor fibre 5 of described direct impulse light is through described circulator 4
Figure 2010102868576100002DEST_PATH_IMAGE005
,
Figure 291256DEST_PATH_IMAGE003
Port enters described polarization beam apparatus 6.
4) described polarization beam apparatus 6 is with after Rayleigh scattering signal light is divided into orthogonal two polarization modes dorsad, and two output ports through described polarization beam apparatus 6 enter two input ports that described balance is amplified photoelectric commutator 7 respectively.
5) described balance is amplified photoelectric commutator 7 and described two input polarization light intensities is subtracted each other and be converted to the output port that electric signal amplifies photoelectric commutator 7 through described balance and arrive described data acquisition unit 8.
6) data of described data acquisition unit 8 acquisitions are passed to described data processing unit 9 and are done the post analysis processing.
Above embodiment only is a better embodiment of the present invention, but protection scope of the present invention is not limited thereto, and does not break away from any modification and local replacement of spirit and scope of the invention, all should be encompassed within protection scope of the present invention.

Claims (8)

1. Polarization-Sensitive distributed perturbation method for sensing, it is characterized in that in the sensor fibre or react optical fiber by a circulator to the polarization state measurement of the light signal of Rayleigh scattering dorsad that detectable signal produced of sensor fibre and whether be subjected to external interference along the line, at first use a polarization beam apparatus to be divided into mutually orthogonal two-way polarized light in the sensor fibre or through the tested rayleigh backscattering light signal of circulator output, then this two-way polarized light signal is imported balance respectively and amplified two input ports of photoelectric commutator, the polarization state that draws two ways of optical signals changes the poor of the light intensity that causes.
2. the Polarization-Sensitive distributed perturbation method for sensing based on polarization beam apparatus and balance amplification photoelectric commutator according to claim 1 is characterized in that the monitoring step of described sensor-based system comprises:
1) described function generator (1) sends two synchronous triggering signals and is respectively applied for triggering described pulsed laser (2) and described data acquisition unit (8);
2) the direct impulse light signal of described pulsed laser 2 outputs enters described sensor fibre (5) through two ports of described Polarization Controller 3, described circulator (4);
3) light of Rayleigh scattering signal dorsad that produces in described sensor fibre (5) of described direct impulse light enters described polarization beam apparatus (6) through other two ports of described circulator (4);
4) described polarization beam apparatus (6) is with after Rayleigh scattering signal light is divided into orthogonal two polarization modes dorsad, and two output ports through described polarization beam apparatus (6) enter two input ports that described balance is amplified photoelectric commutator (7) respectively;
5) described balance is amplified photoelectric commutator (7) and described two input polarization light intensities is subtracted each other and be converted to the output port that electric signal amplifies photoelectric commutator (7) through described balance and arrive described data acquisition unit (8);
6) data of described data acquisition unit (8) acquisition are passed to described data processing unit (9) and are done the post analysis processing.
3. the Polarization-Sensitive distributed perturbation method for sensing based on polarization beam apparatus and balance amplification photoelectric commutator according to claim 2, one of them of two synchronous triggering signals that it is characterized in that described function generator (1) output is used to trigger the trigger pip of described data acquisition unit (8), the passage that uses described data acquisition unit 8 also can not use any trigger pip from trigger pip.
4. describedly amplify the Polarization-Sensitive distributed perturbation method for sensing of photoelectric commutator according to claim 2 or 3, it is characterized in that described polarization beam apparatus (6) is with monitoring step 4 based on polarization beam apparatus and balance) photolysis of described Rayleigh scattering signal dorsad is the orthogonal flashlight of two-way polarization mode.
5. describedly amplify the Polarization-Sensitive distributed perturbation method for sensing of photoelectric commutator according to claim 2 or 3, it is characterized in that the data-signal that described data processing unit (9) is adopted described data acquisition unit (8) does analyzing and processing based on polarization beam apparatus and balance.
6. according to claim 2 or 3 described Polarization-Sensitive distributed perturbation method for sensing based on polarization beam apparatus and balance amplification photoelectric commutator, it is characterized in that described data processing unit (9) carries out the time-domain analysis processing if then tackle signal after the no nonzero frequency of frequency-region signal discovery when signal being carried out the frequency-domain analysis processing, be about to described time-domain signal and original time-domain signal compares, if exist polarization state to change, illustrate that then described sensor fibre is subjected to extraneous extruding to wait the interference of static stress.
7. Polarization-Sensitive distributed perturbation sensor-based system, it is characterized in that, comprise function generator (1), pulsed laser (2), Polarization Controller (3), circulator (4), sensor fibre (5), polarization beam apparatus (6), balance is amplified photoelectric commutator (7), data acquisition module (8), data processing module (9); Two synchronous triggering output ports of described function generator (1) connect respectively and trigger the input end of described pulsed laser (2) and the triggering input port of described data acquisition unit (8); The output terminal of described pulsed laser (2) connects the input end of described Polarization Controller (3); The output terminal of described Polarization Controller (3) connects described circulator (4) port
Figure 884324DEST_PATH_IMAGE002
The port of described circulator (4)
Figure 157174DEST_PATH_IMAGE003
Connect described sensor fibre (5); Described circulator (4) port
Figure 886095DEST_PATH_IMAGE004
The input end that connects described polarization beam apparatus (6); Two output ports of described polarization beam apparatus (6) connect two input ports that balance is amplified photoelectric commutator (7); Described balance is amplified the data acquisition input port of the output port connection data acquisition unit (8) of photoelectric commutator (7); The output terminal of described data acquisition unit (8) connects the input end of data processing unit (9).
8. the Polarization-Sensitive distributed perturbation sensor-based system based on polarization beam apparatus and balance amplification photoelectric commutator according to claim 7 is characterized in that two output ports of described polarization beam apparatus (6) link to each other with two input ports of described balance amplification photoelectric commutator (7) respectively.
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CN102809421A (en) * 2011-06-01 2012-12-05 电子科技大学 Multi-point localizable distribution-type optical-fiber vibration sensor based on polarization-state differential detection
CN104833378A (en) * 2015-03-06 2015-08-12 苏州光格设备有限公司 Method for identifying interference signal of optical fiber perimeter system
CN106248213A (en) * 2016-08-03 2016-12-21 电子科技大学 A kind of method and system of distributed measurement optical fiber polarisation transmission matrix
CN106683310A (en) * 2017-03-15 2017-05-17 河南理工大学 Laser alarm for preventing conventional optical interference
CN108507760A (en) * 2018-05-31 2018-09-07 中国南方电网有限责任公司超高压输电公司贵阳局 A kind of high-voltage convertor station energy-transmission optic fibre link state on-line measuring device
CN109724634A (en) * 2018-12-29 2019-05-07 武汉光谷互连科技有限公司 A kind of the light coherent receiver and method of automatic polarization equilibrium
CN110595737A (en) * 2019-08-22 2019-12-20 南京大学 Optical characteristic measuring system and measuring method for micro-area
CN114993448A (en) * 2022-06-09 2022-09-02 西北大学 Long-distance distributed vibration monitoring device and monitoring method
CN114993447A (en) * 2022-06-09 2022-09-02 西北大学 Distributed regional disturbance monitoring device and disturbance monitoring method

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CN101324441A (en) * 2008-07-25 2008-12-17 北京交通大学 Control system of Mach-Zehnder optical fiber interferometer polarization decline and phase decline
CN101344452A (en) * 2008-08-22 2009-01-14 北京交通大学 Method and device for implementing polarization sensitive optical time domain reflection technology by using piezoelectric ceramic
CN101464166A (en) * 2009-01-08 2009-06-24 北京航空航天大学 Optical fiber distributed perturbation sensor and method for implementing perturbation positioning

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US5574553A (en) * 1994-12-27 1996-11-12 The United States Of America As Represented By The Secretary Of The Air Force Ladar receiver incorporating an optical amplifier and polarization optical mixer
CN101324441A (en) * 2008-07-25 2008-12-17 北京交通大学 Control system of Mach-Zehnder optical fiber interferometer polarization decline and phase decline
CN101344452A (en) * 2008-08-22 2009-01-14 北京交通大学 Method and device for implementing polarization sensitive optical time domain reflection technology by using piezoelectric ceramic
CN101464166A (en) * 2009-01-08 2009-06-24 北京航空航天大学 Optical fiber distributed perturbation sensor and method for implementing perturbation positioning

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102809421A (en) * 2011-06-01 2012-12-05 电子科技大学 Multi-point localizable distribution-type optical-fiber vibration sensor based on polarization-state differential detection
CN104833378A (en) * 2015-03-06 2015-08-12 苏州光格设备有限公司 Method for identifying interference signal of optical fiber perimeter system
CN104833378B (en) * 2015-03-06 2017-05-17 苏州光格设备有限公司 Method for identifying interference signal of optical fiber perimeter system
CN106248213A (en) * 2016-08-03 2016-12-21 电子科技大学 A kind of method and system of distributed measurement optical fiber polarisation transmission matrix
CN106248213B (en) * 2016-08-03 2017-12-26 电子科技大学 A kind of method and system of distributed measurement optical fiber polarisation transmission matrix
CN106683310B (en) * 2017-03-15 2022-03-08 河南理工大学 Anti-interference laser alarm
CN106683310A (en) * 2017-03-15 2017-05-17 河南理工大学 Laser alarm for preventing conventional optical interference
CN108507760A (en) * 2018-05-31 2018-09-07 中国南方电网有限责任公司超高压输电公司贵阳局 A kind of high-voltage convertor station energy-transmission optic fibre link state on-line measuring device
CN109724634B (en) * 2018-12-29 2022-01-18 武汉光谷互连科技有限公司 Optical coherent receiving method with automatic polarization equalization
CN109724634A (en) * 2018-12-29 2019-05-07 武汉光谷互连科技有限公司 A kind of the light coherent receiver and method of automatic polarization equilibrium
CN110595737A (en) * 2019-08-22 2019-12-20 南京大学 Optical characteristic measuring system and measuring method for micro-area
CN114993448A (en) * 2022-06-09 2022-09-02 西北大学 Long-distance distributed vibration monitoring device and monitoring method
CN114993447A (en) * 2022-06-09 2022-09-02 西北大学 Distributed regional disturbance monitoring device and disturbance monitoring method
CN114993447B (en) * 2022-06-09 2023-03-10 西北大学 Distributed regional disturbance monitoring device and disturbance monitoring method
CN114993448B (en) * 2022-06-09 2023-04-07 西北大学 Long-distance distributed vibration monitoring device and monitoring method

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