CN108709574A - A kind of fiber grating sensing system for Wavelet Singularity detection - Google Patents
A kind of fiber grating sensing system for Wavelet Singularity detection Download PDFInfo
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- 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
- G01D5/35306—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 an interferometer arrangement
- G01D5/35309—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 an interferometer arrangement using multiple waves interferometer
- G01D5/35316—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 an interferometer arrangement using multiple waves interferometer using a Bragg gratings
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- 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
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Abstract
The present invention provides a kind of fiber grating sensing system for Wavelet Singularity detection, the system includes successively according to optical path direction：Light source, Active Optical Fiber, circulator, fiber-optic grating sensor, (FBG) demodulator 105, and last output is connected to user interface, wherein, light source is for sending out laser beam, the laser beam enters circulator through Active Optical Fiber, it goes forward side by side and one steps into and be incident upon fiber-optic grating sensor, (FBG) demodulator carries out fiber grating sensing demodulation peak-seeking for demodulating from the reflected reflected spectrum data of fiber-optic grating sensor, to acquisition fiber grating reflection spectrum data.Peak-seeking effect of the present invention is more preferable, closer to actual value.
Description
It is on 03 09th, 2016 that the application, which is the applying date, application No. is CN201610131661.7, entitled base
In the divisional application of the FBG sensing and demodulating Peak Search Methods of Wavelet Singularity detection.
Technical field
The present invention relates to a kind of fiber grating sensing demodulation Peak Search Methods, more particularly to a kind of to be detected for Wavelet Singularity
Fiber grating sensing system.
Background technology
In general, fiber grating (Fiber Bragg Grating, FBG) is current most representational optical fiber passive device
One of part, it have electromagnetism interference, wide dynamic range, corrosion-resistant, high sensitivity, light weight and it is small, intelligence can be embedded to
, there are bright prospects in the features such as structure in the Application in Sensing of each physical quantity.The basic composition such as Fig. 1 of fiber grating sensing system
It is shown.Fiber-optic grating sensor is to detect the change of the measurands such as temperature or strain by detecting the drift of its centre wavelength
Change, therefore the determination of the wavelength peak position of fiber-optic grating sensor is most important.
In existing research, common peak-seeking algorithm has：Centroid method (the power weightings method of average), Gauss curve fitting method are more
Item formula fitting, Cubic Spline Fitting are fitted, genetic algorithm and ant group algorithm etc. based on RBF (radial basis function).But in optical fiber light
On the real-time Transient Analysis of grid sensing and demodulating signal Prague centre wavelength drift, commonly uses peak-seeking algorithm and exist seriously not
Foot, therefore, it is necessary to a kind of fiber grating sensing systems for Wavelet Singularity detection.
Invention content
The purpose of the present invention is to provide a kind of fiber grating sensing system for Wavelet Singularity detection, the systems
Include successively according to optical path direction：
Light source, Active Optical Fiber, circulator, fiber-optic grating sensor, (FBG) demodulator 105 and last output are connected to use
Family interface, wherein light source enters circulator for sending out laser beam, the laser beam through Active Optical Fiber, and further
It is incident to fiber-optic grating sensor, (FBG) demodulator is for demodulating from the reflected reflected spectrum data of fiber-optic grating sensor；
The (FBG) demodulator acquisition fiber grating reflection spectrum data carry out fiber grating sensing demodulation peak-seeking, including：
A) fiber grating reflection spectrum data are acquired；
B) fiber grating reflection spectrum of acquisition is divided into multistage by the way that intensity threshold value is arranged；
C) cubic spline interpolation is carried out to every section of fiber grating reflection spectrum；
D) multi-scale wavelet transformation is carried out using Mexhat small echos；
E) modulus maximum of wavelet transformation on each scale is obtained successively and wavelet transformation peak is obtained according to the modulus maximum
Road location；
F) judge whether the road location at each scale wavelet transform peak is peak maximum position, if not then return to step e), such as
Fruit is to enter step g)；
G) according to the pixel of fiber grating reflection spectrum and wavelength correspondence formula, peak maximum position is calculated and corresponds to picture
Centre wavelength value at vegetarian refreshments position.
Preferably, the wavelet basis includes Daubechies (dbN) small echo, coiflet (coifN) small echo, Morlet small
Wave, Meyer small echos, spline wavelets and Mexican hat small echos.
Preferably, Mexican hat small echos are chosen and carries out peak-seeking analysis.
Preferably, the (FBG) demodulator is connected with user interface, detected by analyzing reflected spectrum data temperature or
The variation of the measurands such as strain.
Preferably, the wavelet basis selected in the step d will meet the compact schemes in certain section and enough vanishing moment ranks
Number.
Preferably, in the peak-seeking algorithm of Demodulation System for Fiber Bragg, the reflectance spectrum output intensity of fiber grating can
With with formula (1) approximate representation：
Wherein, I0 indicates reflectance spectrum peak strength；λsIndicate that reflection spectral intensity is equal to corresponding centre wavelength value；ΔλsTable
It is shown as the broadbands 3dB of reflectance spectrum；λ indicates the initial center wavelength of reflectance spectrum.
Preferably, in the peak-seeking algorithm of Demodulation System for Fiber Bragg, the matched curve of the reflectance spectrum of fiber grating
Using formula (2)
Wherein, y0 indicates reflectance spectrum peak strength；X indicates the initial center wavelength value of reflectance spectrum；X0 indicates that reflection is general strong
Degree is equal to the corresponding centre wavelength values of y0.
It should be appreciated that aforementioned description substantially and follow-up description in detail are exemplary illustration and explanation, it should not
As the limitation to the claimed content of the present invention.
Description of the drawings
With reference to the attached drawing of accompanying, the more purposes of the present invention, function and advantage are by the as follows of embodiment through the invention
Description is illustrated, wherein：
Fig. 1 diagrammatically illustrates fiber grating sensing system of the present invention for being detected based on Wavelet Singularity；
Fig. 2 shows the specific steps of fiber grating sensing demodulation Peak Search Method of the present invention；
Fig. 3 schematically shows the schematic diagram for being segmented reflectance spectrum by the way that threshold values is arranged；
Fig. 4 shows the schematic diagram of wavelet transformation of the present invention；
Fig. 5 gives wavelet transformation knot of the different wavelet basis of three kinds carried out to optical grating reflection spectrum signal under different scale
Fruit.
Specific implementation mode
By reference to exemplary embodiment, the purpose of the present invention and function and the side for realizing these purposes and function
Method will be illustrated.However, the present invention is not limited to exemplary embodiment as disclosed below；Can by different form come
It is realized.The essence of specification is only to aid in the detail of the various equivalent modifications Integrated Understanding present invention.
Hereinafter, the embodiment of the present invention will be described with reference to the drawings.In the accompanying drawings, identical reference numeral represents identical
Or similar component or same or like step.
The present invention provides a kind of fiber grating sensing demodulation Peak Search Method detected based on Wavelet Singularity, and this method utilizes
Method of wavelet singularity detection can be accurately located fiber grating reflection spectrum peak, significantly improve qualitative point of optical fiber grating sensing
Peak-seeking precision in analysis and quantitative analysis.
Fiber grating (Fiber Bragg Grating, fiber grating) is current most representational optical fiber passive device
One of part, it have electromagnetism interference, wide dynamic range, corrosion-resistant, high sensitivity, light weight and it is small, intelligence can be embedded to
, there are bright prospects in the features such as structure in the Application in Sensing of each physical quantity.Fiber-optic grating sensor is by detecting its center
Wavelength drifts about to detect the variation of the measurands such as temperature or strain, therefore the wavelength peak position of fiber-optic grating sensor
Determination it is most important.
The basic composition of fiber grating sensing system according to the present invention for being detected based on Wavelet Singularity is such as Fig. 1 institutes
Show.The system includes successively according to optical path direction：Light source 101, Active Optical Fiber 102, circulator 103, fiber-optic grating sensor
104 (fiber Bragg grating sensors), (FBG) demodulator 105 and last output are connected to user interface 106.Specifically, such as
Shown in Fig. 1, for sending out laser beam, the laser beam enters circulator 103 through Active Optical Fiber 102, goes forward side by side light source 101
One steps into and is incident upon fiber-optic grating sensor 104 (fiber Bragg grating sensor), and (FBG) demodulator 105 is for demodulating from fiber grating
The reflected reflected spectrum data of sensor, (FBG) demodulator 105 can be connected with user interface 106, and (FBG) demodulator 105 is by dividing
Analysis reflected spectrum data and detect the variations of the measurands such as temperature or strain.
The present invention proposes a kind of fiber grating sensing demodulation Peak Search Method detected based on Wavelet Singularity, as shown in Fig. 2,
The method of the present invention includes following steps：
Step 201：Acquire fiber grating reflected spectrum data；Preferably, the (FBG) demodulator in system shown in Figure 1 can be utilized
105 are acquired work.
Step 202：Fiber grating reflection spectrum is simultaneously divided into multistage by setting intensity threshold value according to set threshold values；The setting of threshold values
It can be set and be adjusted according to demand.Fiber grating reflection spectrum is schematically as shown in Figure 3.
Step 203：Cubic spline interpolation is carried out to every section of fiber grating reflection spectrum；
Step 204：Multi-scale wavelet transformation is carried out using Mexhat small echos；
Step 205：The road location of the modulus maximum of wavelet transformation and wavelet transformation peak on each scale is obtained successively；
Step 206：Judge whether the road location at each scale wavelet transform peak is peak maximum position pt, if not then returning to step
Rapid 205, if yes then enter step 207；
Step 207：According to the pixel of fiber grating reflectance spectrum and wavelength correspondence formula, summit point is calculated
Set the centre wavelength value at pt corresponding pixel points position.Peak-seeking result thereby is achieved.
Specifically, the wavelet basis selected in step 204 will meet the compact schemes in certain section and enough vanishing moment exponent numbers,
It thus can effectively eliminate noise and find singular point.The available wavelet basis of the present invention include Daubechies (dbN) small echo,
Coiflet (coifN) small echo, Morlet small echos, Meyer small echos, spline wavelets and Mexican hat small echos etc., Fig. 5 gives
Wavelet transform result of the three kinds of different wavelet basis that optical grating reflection spectrum signal is carried out under different scale.
If wavelet transform function Ψs(x) there is n ranks vanishing moment and tightly prop up, then certainly exist compactly support function #s *,
So that
Definition
Then wavelet transformation formula is：
I.e. wavelet function has n rank vanishing moments, then its wavelet transformation is just comparable to a n rank the multi-scale differential operator.
As n=1, wavelet transform function has single order vanishing moment, then its wavelet transformation is proportional to f* θs(x) first derivative, i.e., it is public
Formula (4)
Formula (5) W2F (s, x) is proportional to f* θs(x) second dervative.
Formula (6) is Mexican hat wavelet basis functions
S is change of scale, and mould can be obtained in the local model maximum value point line obtained through wavelet transformation in scale space (s, x)
Maximum line.
Preferably, the present invention chooses Mexican hat small echos and carries out peak-seeking analysis.Mexican hat wavelet basis is to mutation
Signal peak singular point has good locating features and analysis precision.Mexican hat wavelet basis functions see above formula (6) and its
Frequency domain analytic expression (7).
If wavelet basis has n rank vanishing moments, and n ranks can be micro-, has compact schemes.Here n is positive integer, singularity exponents
α≤n, reflection spectrum signal f (x) ∈ L2(R), if in x0Neighborhood in and all scale, there are a constant A to meet formula
(8)：
|W f (s, x) |≤A(sα+|x-x0|α) (8)
Reflection spectrum signal f (x) can be determined in point x using wavelet transformation according to conclusions0Singularity exponents α.From formula
(8) it is found that singular point is distributed on module maximum line, singularity exponents α is not equal to 1, and singularity exponents α >0, then claim anti-
Spectrum signal f (x) is penetrated in x0Point is unusual, and fiber grating reflection spectrum Signal Singularity is determined using wavelet transformation to realize.
Specifically, steps are as follows for the realization of step 205：If a smooth function θ (x), and meet following condition
With
And it definesDefine two wavelet functions
For f (x) ∈ L2(R), wavelet transformation is
f*θsPlay a part of smoothing f (x).To each scale s, W1F (s, x), W2F (s, x) is proportional to f* θ respectivelys
(x)|First derivative and second dervative, Fig. 4 intuitively illustrates the relationship between them.
As shown in Figure 4, the singular point on f (x), by wavelet transformation, in W1Maximum is shown as on f (s, x), and in W2f
It is zero crossing on (s, x).Therefore singular point position, which can be converted into, seeks W1The maximum or W of f (s, x)2The zero crossing of f (s, x).
Since zero crossing is easily interfered by noise, and W2That the zero crossing of f (s, x) reflects sometimes is f* θsTurning point, to singularity
Judgement be not necessarily to, therefore use W1The maximum of f (s, x) is more convenient.
W1The maximum of f (s, x) has transitivity with s, if localized mode pole is not present in small echo on smaller scale
Big value, then can not possibly have singular point in the neighborhood.So the presence of singular point and each scale have with modulus maximum
It closes.Under normal circumstances, scale from big to small when, modulus maximum point is converted into singular point, constitutes a Modulus maximum line.According to
This, using the modulus maximum point of retrieval wavelet conversion coefficient, so that it may to detect the catastrophe point of signal, that is, can determine that fiber grating
The peak position of transducing signal.
According to the above-mentioned fiber grating sensing demodulation Peak Search Method based on Wavelet Singularity detection, the present invention also provides one
A specific embodiment, the initial value of fiber bragg grating centre wavelength is 1535nm in embodiment, however passes through normal light
Spectrometer obtains the reflectance spectrum of fiber grating, and the resolution ratio that conventional spectrograph is arranged is 0.02nm, sampling number 1000, scanning strip
Width is 2nm, and the centre wavelength to measure fiber bragg grating original spectrum is 1535.0835nm.
In the peak-seeking algorithm of Demodulation System for Fiber Bragg, the reflectance spectrum output intensity of fiber grating can use formula
(13) approximate representation, matched curve use formula (14).
Wherein, I0 indicates reflectance spectrum peak strength；λsIndicate that reflection spectral intensity is equal to corresponding centre wavelength value；ΔλsTable
It is shown as the broadbands 3dB of reflectance spectrum；λ indicates the initial center wavelength of reflectance spectrum.
Wherein, y0 indicates reflectance spectrum peak strength；X indicates the initial center wavelength value of reflectance spectrum；X0 indicates that reflection is general strong
Degree is equal to the corresponding centre wavelength values of y0.
Table 1 show based on Gauss curve fitting method peak-seeking result and Wavelet Singularity detection peak-seeking method between accuracy comparison,
Give positioning accuracy of two kinds of peak-seeking arithmetic results relative to original spectrum simultaneously.
1 algorithms of different positioning accuracy of table compares
The Singularity Detection of wavelet analysis can also be obtained for optical fiber grating sensing unstable signal through this embodiment
Peak-seeking effect it is more preferable, closer to actual value.Method of wavelet singularity detection can be accurately located fiber grating reflection spectrum peak, energy
The singularity of quantitative analysis signal, and realize peak-seeking, there is important practical value in engineer application.Wavelet Singularity detection side
Method is influenced the peak-seeking effect of fiber grating sensing demodulation by multiple factors, such as wavelet basis function used, wavelet transformation
The determination of the selection of coefficient and noise jamming and some design parameters, in practical applications, it is also necessary to comprehensive according to actual conditions
It closes and considers each factor.
The attached drawing is only schematical and draws not in scale.Although have been combined preferred embodiment to the present invention into
Description is gone, it is to be understood that protection scope of the present invention is not limited to embodiment as described herein.
Explanation in conjunction with the present invention disclosed here and practice, the other embodiment of the present invention is for those skilled in the art
It all will be readily apparent and understand.Illustrate and embodiment is regarded only as being exemplary, true scope of the invention and purport are equal
It is defined in the claims.
Claims (7)
1. a kind of fiber grating sensing system for Wavelet Singularity detection, which is characterized in that the system is according to light path side
To including successively：
Light source, Active Optical Fiber, circulator, fiber-optic grating sensor, (FBG) demodulator 105 and last output are connected to user and connect
Mouthful, wherein for light source for sending out laser beam, the laser beam enters circulator through Active Optical Fiber, goes forward side by side and one steps into and penetrate
To fiber-optic grating sensor, (FBG) demodulator is for demodulating from the reflected reflected spectrum data of fiber-optic grating sensor；
The (FBG) demodulator acquisition fiber grating reflection spectrum data carry out fiber grating sensing demodulation peak-seeking, including：
A) fiber grating reflection spectrum data are acquired；
B) fiber grating reflection spectrum of acquisition is divided into multistage by the way that intensity threshold value is arranged；
C) cubic spline interpolation is carried out to every section of fiber grating reflection spectrum；
D) multi-scale wavelet transformation is carried out using Mexhat small echos；
E) modulus maximum of wavelet transformation on each scale is obtained successively and the road at wavelet transformation peak is obtained according to the modulus maximum
Location；
F) judge whether the road location at each scale wavelet transform peak is peak maximum position, if not then return to step e), if it is
It then enters step g)；
G) according to the pixel of fiber grating reflection spectrum and wavelength correspondence formula, peak maximum position corresponding pixel points are calculated
Centre wavelength value at position.
2. peak-seeking system according to claim 1, it is characterised in that：The wavelet basis includes Daubechies (dbN) small
Wave, coiflet (coifN) small echo, Morlet small echos, Meyer small echos, spline wavelets and Mexican hat small echos.
3. peak-seeking system according to claim 2, it is characterised in that：It chooses Mexican hat small echos and carries out peak-seeking analysis.
4. Peak Search Method according to claim 1, it is characterised in that：The (FBG) demodulator is connected with user interface, passes through
Analysis reflected spectrum data and detect the variations of the measurands such as temperature or strain.
5. Peak Search Method according to claim 1, it is characterised in that：The wavelet basis selected in the step d will meet one
Determine the compact schemes in section and enough vanishing moment exponent numbers.
6. Peak Search Method according to claim 1, it is characterised in that：In the peak-seeking algorithm of Demodulation System for Fiber Bragg
In, the reflectance spectrum output intensity of fiber grating can use formula (1) approximate representation：
Wherein, I0Indicate reflectance spectrum peak strength；λsIndicate that reflection spectral intensity is equal to corresponding centre wavelength value；ΔλsIt is expressed as
The broadbands 3dB of reflectance spectrum；λ indicates the initial center wavelength of reflectance spectrum.
7. Peak Search Method according to claim 1, it is characterised in that：In the peak-seeking algorithm of Demodulation System for Fiber Bragg
In, the matched curve of the reflectance spectrum of fiber grating uses formula (2)
Wherein, y0Indicate reflectance spectrum peak strength；X indicates the initial center wavelength value of reflectance spectrum；x0Indicate that reflecting general intensity is equal to
y0Corresponding centre wavelength value.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN109632712A (en) * | 2019-01-16 | 2019-04-16 | 北京信息科技大学 | The femtosecond direct write FBG temperature and refractive index measurement method of optical fiber tapered structure |
| CN113076962A (en) * | 2021-05-14 | 2021-07-06 | 电子科技大学 | Multi-scale target detection method based on micro neural network search technology |
| CN114861723A (en) * | 2022-05-07 | 2022-08-05 | 重庆邮电大学 | System and method applied to fiber Bragg grating demodulation |
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| CN107490397B (en) * | 2016-09-14 | 2018-05-04 | 北京卫星环境工程研究所 | High-accuracy self-adaptation filters the quick Peak Search Method of FBG spectrum |
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| CN105841723A (en) | 2016-08-10 |
| CN108709574B (en) | 2020-07-31 |
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Application publication date: 20181026 Assignee: NINGBO TIANDE INNOVATION INTELLIGENT TECHNOLOGY Co.,Ltd. Assignor: Beijing Information Science & Technology University Contract record no.: X2020990000715 Denomination of invention: A fiber Bragg grating sensing system for wavelet singularity detection Granted publication date: 20200731 License type: Common License Record date: 20201230 |