CN103292889A - Distributed optical fiber vibrating sensor vibration source locating method - Google Patents
Distributed optical fiber vibrating sensor vibration source locating method Download PDFInfo
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- CN103292889A CN103292889A CN2013101948859A CN201310194885A CN103292889A CN 103292889 A CN103292889 A CN 103292889A CN 2013101948859 A CN2013101948859 A CN 2013101948859A CN 201310194885 A CN201310194885 A CN 201310194885A CN 103292889 A CN103292889 A CN 103292889A
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Abstract
The invention discloses a distributed optical fiber vibrating sensor vibration source locating method. In the distributed optical fiber vibrating sensor vibration source locating method, an optical pulse transmitter, an optical signal receiver and a signal processor are adopted, the optical signal receiver and the signal processor calculate a group of vibration signals distributed along an optical cable, and cross-correlation functions of the maximum vibration point and other positions are obtained by other relevant calculations. According to the cross-correlation functions, a vibration source can be located. Spatial position where vibration occurs can be located according to the spatial distribution features of the cross-correlation values of vibration.
Description
Technical field
The present invention relates to a kind of distributed optical fiber vibration sensor vibration source localization method.
Background technology
20th century the mid-1970s, along with the development of light transmitting fiber and Fibre Optical Communication Technology, Fibre Optical Sensor begins to develop rapidly.Fibre Optical Sensor is carrier with the light wave, optical fiber is media, the novel sensing technology of perception and the extraneous measured signal of transmission, by measurand (as stress, temperature, pressure, electric field, magnetic field etc.) the transmission light in the optical fiber is modulated, characteristics such as transmission light intensity, phase place, frequency or polarization state are changed, by modulated light signal is detected, draw a kind of novel sensor of measurand at receiving end.Compare with traditional sensors, Fibre Optical Sensor has its unique advantage, as non-contact measurement, highly sensitive, response speed is fast, anti-electromagnetic interference (EMI), UHV (ultra-high voltage) insulation, high-temperature corrosion resistance, burn-proof and explosion prevention, deflection flexibly, measuring object are extensive etc.Thereby has urgent application demand aspect many heavy constructions, as railway operation, water conservancy and hydroelectric project, bridge tunnel, large-scale exhibition center and meeting-place, oil and gas pipeline, large ship, the safety and health monitoring of environment and highway engineering etc. etc., aspect monitoring in real time, long distance control system on a large scale based on Fibre Optical Sensor, can be used for the on-the-spot and great politics of heavy construction, economical, the circumference security protection in military base, by real-time monitoring key area, when accident takes place, can accurately and timely obtain notice and confirm the event occurrence positions, so that loss is dropped to bottom line.Therefore studying the distributing optical fiber sensing positioning system is a problem that application prospect and practical significance are arranged very much.
In recent years, the research of interference type distributed optical fiber sensor-based system has obtained extensive concern at aspects such as pipe detection, security protection detections.Owing to based on the phase place modulation principle, carry the active position information of signal message and signal in the interference signal, in order therefrom to isolate the positional information of signal, proposed the interference type distributed optical fiber sensor-based system that multiple employing compound interference structure realizes the location.Adopt the compound interference structure to realize the method for location, utilize the method location of time domain phase place ratio, by on time domain, two-way being interfered demodulation phase to be divided by to realize the location.Yet this method is very high to the requirement of restituted signal, and the interference that superposes on the sensor fibre circuit will produce very big influence to it, thereby bearing accuracy is lower.
In a word, distributed optical fiber sensing system belongs to the phase modulation-type Fibre Optical Sensor in essence now, act on the external disturbance signal on the optical fiber, according to photoelastic effect, the phase place that causes transmission light in the optical fiber changes, by interference technique (wide spectrum light source interference), obtain to comprise the two-way interference light interference signal of external disturbance information.Interference signal is carried out processing such as opto-electronic conversion, amplification, A/D conversion, obtain comprising the digital signal of external disturbance information.For fear of the interference of vibration wave at a distance to guarded region, need know the position of vibration source.When vibration source with a certain distance from the distance of optical cable greater than after, then not as analyzing and the information source of alarm.In order to obtain spatial information, need to adopt method for processing signals, utilize the phase place reduction technique, from the acquisition digital signal, demodulate phase-changing signal.But in fact, because interference of noise is difficult to reduce fully original vibration phase.Therefore, cross-correlation technique is studied a kind of common technique of signal correlation just, and it analyzes the correlativity of two paths of signals by cross correlation function, thereby obtains the curve of cross correlation function, thereby knows the variation of different distance Curve, and finds the variation of vibration source.
Summary of the invention
The present invention seeks to the deficiency at the prior art existence, because the interference of noise and other environmental factor, the phase place reduction is difficult to the original vibration signal of reduction, thereby processing brings a lot of troubles to signal.Cross-correlation technique is studied a kind of common technique of signal correlation just, and it analyzes the correlativity of two paths of signals by cross correlation function, thereby obtains the simple crosscorrelation curve between two signals.Not ideal enough in the signal spectrum characteristic, perhaps under the situation that signal to noise ratio (S/N ratio) S/N is lower, the peak value of vibration source can be subjected to The noise, and the accuracy of precision and detection and location is exerted an influence.In order to slacken noise to the influence of vibration signal, we provide a kind of distributed optical fiber vibration sensor vibration source localization method, and it utilizes the curve of the cross correlation function of a plurality of signals to judge the position of vibration source.
The present invention adopts following technical scheme for achieving the above object: a kind of distributed optical fiber vibration sensor vibration source localization method comprises the steps:
(1) light pulse transmitter emission light pulse;
(2) optical receiver receives above-mentioned light pulse, and intensity signal is converted to voltage signal;
(3) signal processor converts above-mentioned voltage signal to vibration signal; At this moment, each point can have a time dependent vibration signal on the optical cable
(t); Wherein,
(t) represent on the optical cable from the centre of oscillation
Distance is the vibration signal of z;
(4) in the signal processor of step (3),
(t) seek out the centre of oscillation in, the vibration signal in the centre of oscillation is designated as
(t); Wherein,
(t) vibration signal of close focus on the expression optical cable;
(5) in the signal processor of step (4), on each distance z point
(t) do cross-correlation calculation and obtain cross correlation function: R (z)=xcorr (
,
); Cross-correlation function value R (z) is carried out computing, thereby judge the position of vibration source.
Further, the disposal route of described cross-correlation function value R (z) comprises at least:
A), to the process of fitting treatment of functional value R (z): in test site, vibration source is fixed on position with a certain distance from optical cable, every conversion is once apart from the curve data that just records a functional value R (z), functional value R (z) is carried out match with the arbitrary function form, fitting coefficient has just formed corresponding relation with oscillation distances, just obtains corresponding distance results according to this fitting coefficient; Perhaps
B), to the pattern recognition process of functional value R (z): in test site, vibration source is fixed on position with a certain distance from optical cable, every conversion once distance is just recorded the curve data of many functional value R (z) as sample, every meter is made as a classification, the sample that surpasses preset distance is made as a new classification separately, and a plurality of samples are carried out pattern drill; When new data being carried out distance calculating, the functional value R (z) that calculates to be sent into the algorithm for pattern recognition module of training classify, classification results is exactly distance results.
Further, obtaining the mathematical models that two of described cross correlation function receives signals is:
Wherein,
,
Be that average is 0 additive noise; Signal
,
With noise
,
Uncorrelated.
Beneficial effect of the present invention: the method that was used for the optical fibre vibration sensor location in the past all is based on the phase place reduction, owing to be subjected to the interference of noise and external environment, phase place when being difficult to that phase place reverted to vibration, this has brought a lot of technical difficulties to our location.Therefore the correlativity that has proposed to utilize their cross correlation to analyze two paths of signals obtains their cross correlation, thereby obtains vibration source from the range information of optical cable.Concerning prior art, the vibroseis location depends on wavefront healing, and wavefront healing needs to be shaken phase information accurately.Characteristics of the present invention be can be capable at vibration wave and phase place can not accurately be recovered even phase place is not right fully situation under, also can calculate the source location.
Description of drawings
Fig. 1 vibration source positioning flow of the present invention figure.
Embodiment
Shown in Figure 1, for a kind of distributed optical fiber vibration sensor vibration source localization method of the present invention, comprise the steps:
(1) light pulse transmitter emission light pulse;
(2) optical receiver receives above-mentioned light pulse, and intensity signal is converted to voltage signal;
(3) signal processor converts above-mentioned voltage signal to vibration signal; At this moment, each point can have a time dependent vibration signal on the optical cable
(t); Wherein,
(t) represent on the optical cable from the centre of oscillation
Distance is the vibration signal of z;
(4) in the signal processor of step (3),
(t) seek out the centre of oscillation in, the vibration signal in the centre of oscillation is designated as
(t); Wherein,
(t) vibration signal of close focus on the expression optical cable;
(5) in the signal processor of step (4), on each distance z point
(t) do cross-correlation calculation and obtain cross correlation function: R (z)=xcorr (
,
); Cross-correlation function value R (z) is carried out computing, thereby judge the position of vibration source.
Wherein, the disposal route of described cross-correlation function value R (z) comprises at least:
A), to the process of fitting treatment of functional value R (z): in test site, vibration source is fixed on position with a certain distance from optical cable, every conversion is once apart from the curve data that just records a functional value R (z), functional value R (z) is carried out match with the arbitrary function form, fitting coefficient has just formed corresponding relation with oscillation distances, just obtains corresponding distance results according to this fitting coefficient; Perhaps
B), to the pattern recognition process of functional value R (z): in test site, vibration source is fixed on position with a certain distance from optical cable, every conversion once distance is just recorded the curve data of many functional value R (z) as sample, every meter is made as a classification, the sample that surpasses preset distance is made as a new classification separately, and a plurality of samples are carried out pattern drill; When new data being carried out distance calculating, the functional value R (z) that calculates to be sent into the algorithm for pattern recognition module of training classify, classification results is exactly distance results.
Wherein, obtaining the mathematical models that two of described cross correlation function receives signals is:
Wherein,
,
Be that average is 0 additive noise; Signal
,
With noise
,
Uncorrelated.
The above only is preferred embodiment of the present invention, and is in order to limit the present invention, within the spirit and principles in the present invention not all, any modification of doing, is equal to replacement, improvement etc., all should be included within protection scope of the present invention.
Claims (3)
1. a distributed optical fiber vibration sensor vibration source localization method is characterized in that, comprises the steps:
(1) light pulse transmitter emission light pulse;
(2) optical receiver receives above-mentioned light pulse, and intensity signal is converted to voltage signal;
(3) signal processor converts above-mentioned voltage signal to vibration signal; At this moment, each point can have a time dependent vibration signal on the optical cable
(t); Wherein,
(t) represent on the optical cable from the centre of oscillation
Distance is the vibration signal of z;
(4) in the signal processor of step (3),
(t) seek out the centre of oscillation in, the vibration signal in the centre of oscillation is designated as
(t); Wherein,
(t) vibration signal of close focus on the expression optical cable;
(5) in the signal processor of step (4), on each distance z point
(t) do cross-correlation calculation and obtain cross correlation function: R (z)=xcorr (
,
); Cross-correlation function value R (z) is carried out computing, thereby judge the position of vibration source.
2. a kind of distributed optical fiber vibration sensor vibration source localization method as claimed in claim 1 is characterized in that, the disposal route of described cross-correlation function value R (z) is comprised at least:
A), to the process of fitting treatment of functional value R (z): in test site, vibration source is fixed on position with a certain distance from optical cable, every conversion is once apart from the curve data that just records a functional value R (z), functional value R (z) is carried out match with the arbitrary function form, fitting coefficient has just formed corresponding relation with oscillation distances, just obtains corresponding distance results according to this fitting coefficient; Perhaps
B), to the pattern recognition process of functional value R (z): in test site, vibration source is fixed on position with a certain distance from optical cable, every conversion once distance is just recorded the curve data of many functional value R (z) as sample, every meter is made as a classification, the sample that surpasses preset distance is made as a new classification separately, and a plurality of samples are carried out pattern drill; When new data being carried out distance calculating, the functional value R (z) that calculates to be sent into the algorithm for pattern recognition module of training classify, classification results is exactly distance results.
3. a kind of distributed optical fiber vibration sensor vibration source localization method as claimed in claim 1 is characterized in that, two mathematical models that receive signal that obtain described cross correlation function are:
Wherein,
,
Be that average is 0 additive noise; Signal
,
With noise
,
Uncorrelated.
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| CN103954349A (en) * | 2014-05-15 | 2014-07-30 | 安徽师范大学 | Lateral positioning method for distributed optical fiber vibration sensing system |
| CN105698915A (en) * | 2016-03-01 | 2016-06-22 | 深圳艾瑞斯通技术有限公司 | Optical fiber vibration source recognition method, device, and system |
| CN105841793A (en) * | 2016-04-15 | 2016-08-10 | 深圳艾瑞斯通技术有限公司 | Optical fiber vibration source identification method, device and system |
| CN105973449A (en) * | 2016-04-15 | 2016-09-28 | 深圳艾瑞斯通技术有限公司 | Method, device and system for recognizing optical fiber vibration source |
| CN107329933A (en) * | 2017-07-14 | 2017-11-07 | 北京知觉科技有限公司 | Fault detection method and device based on Fibre Optical Sensor vibration signal |
| CN107356962A (en) * | 2017-07-14 | 2017-11-17 | 北京知觉科技有限公司 | Micro-seismic Signals localization method and device based on fibre optical sensor |
| CN108931816A (en) * | 2018-08-17 | 2018-12-04 | 山东省科学院激光研究所 | A kind of seismic source location method and device |
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| CN110440901A (en) * | 2019-08-13 | 2019-11-12 | 郑州信大先进技术研究院 | A kind of distributed optical fiber vibration sensing localization method and device based on pulse accumulation |
| CN110672196A (en) * | 2019-08-22 | 2020-01-10 | 北京航天易联科技发展有限公司 | Mobile interference vibration source filtering method based on image operator |
| CN111247401A (en) * | 2018-12-10 | 2020-06-05 | 合刃科技（深圳）有限公司 | Vibration source positioning device and method based on coherent light |
| CN111397850A (en) * | 2020-04-20 | 2020-07-10 | 深圳市特发信息股份有限公司 | Vibration waveform and database sample analysis system for optical cable safety |
| CN111765958A (en) * | 2020-05-26 | 2020-10-13 | 山东大学 | Vibration type identification method and system based on distributed optical fiber vibration radial distance measurement |
| CN113985482A (en) * | 2021-10-28 | 2022-01-28 | 西安科技大学 | Mine earthquake focus positioning method based on coal mine underground communication optical cable |
| CN114777903A (en) * | 2022-04-27 | 2022-07-22 | 浙江大学 | Multi-point vibration detection method and device for optical frequency domain reflectometer based on signal cross correlation |
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| CN103954349A (en) * | 2014-05-15 | 2014-07-30 | 安徽师范大学 | Lateral positioning method for distributed optical fiber vibration sensing system |
| CN103954349B (en) * | 2014-05-15 | 2016-09-14 | 安徽师范大学 | A kind of lateral register method of distributed optical fiber vibration sensing system |
| CN105698915B (en) * | 2016-03-01 | 2019-07-26 | 深圳艾瑞斯通技术有限公司 | A kind of optical fiber Recognition of Vibration Sources method and device, system |
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| CN107329933A (en) * | 2017-07-14 | 2017-11-07 | 北京知觉科技有限公司 | Fault detection method and device based on Fibre Optical Sensor vibration signal |
| CN107356962A (en) * | 2017-07-14 | 2017-11-17 | 北京知觉科技有限公司 | Micro-seismic Signals localization method and device based on fibre optical sensor |
| CN107329933B (en) * | 2017-07-14 | 2020-06-19 | 北京知觉科技有限公司 | Fault detection method and device based on optical fiber sensing vibration signal |
| CN108931816A (en) * | 2018-08-17 | 2018-12-04 | 山东省科学院激光研究所 | A kind of seismic source location method and device |
| CN108931816B (en) * | 2018-08-17 | 2020-01-21 | 山东省科学院激光研究所 | Seismic source positioning method and device |
| CN109269452A (en) * | 2018-09-27 | 2019-01-25 | 武汉康普常青软件技术股份有限公司 | A kind of approximate calculation method of vibration source based on DVS and sensing passage vertical range |
| CN111247401A (en) * | 2018-12-10 | 2020-06-05 | 合刃科技（深圳）有限公司 | Vibration source positioning device and method based on coherent light |
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| CN109872505B (en) * | 2019-03-25 | 2021-02-02 | 武汉理工大学 | Highway guardrail alarm system and method based on optical fiber micro-vibration |
| CN110440901A (en) * | 2019-08-13 | 2019-11-12 | 郑州信大先进技术研究院 | A kind of distributed optical fiber vibration sensing localization method and device based on pulse accumulation |
| CN110440901B (en) * | 2019-08-13 | 2021-08-17 | 郑州信大先进技术研究院 | Distributed optical fiber vibration sensing positioning method and device based on pulse accumulation |
| CN110672196A (en) * | 2019-08-22 | 2020-01-10 | 北京航天易联科技发展有限公司 | Mobile interference vibration source filtering method based on image operator |
| CN110672196B (en) * | 2019-08-22 | 2021-09-24 | 北京航天易联科技发展有限公司 | Mobile interference vibration source filtering method based on image operator |
| CN111397850A (en) * | 2020-04-20 | 2020-07-10 | 深圳市特发信息股份有限公司 | Vibration waveform and database sample analysis system for optical cable safety |
| CN111397850B (en) * | 2020-04-20 | 2021-09-03 | 深圳市特发信息股份有限公司 | Vibration waveform and database sample analysis system for optical cable safety |
| CN111765958A (en) * | 2020-05-26 | 2020-10-13 | 山东大学 | Vibration type identification method and system based on distributed optical fiber vibration radial distance measurement |
| CN113985482A (en) * | 2021-10-28 | 2022-01-28 | 西安科技大学 | Mine earthquake focus positioning method based on coal mine underground communication optical cable |
| CN113985482B (en) * | 2021-10-28 | 2023-11-03 | 西安科技大学 | Ore earthquake focus positioning method based on underground coal mine communication optical cable |
| CN114777903A (en) * | 2022-04-27 | 2022-07-22 | 浙江大学 | Multi-point vibration detection method and device for optical frequency domain reflectometer based on signal cross correlation |
| CN114777903B (en) * | 2022-04-27 | 2023-06-27 | 浙江大学 | Optical frequency domain reflectometer multipoint vibration detection method and device based on signal cross correlation |
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