CN108955734B - Cavity length demodulation method of optical fiber F-P temperature/pressure composite sensor - Google Patents
Cavity length demodulation method of optical fiber F-P temperature/pressure composite sensor Download PDFInfo
- Publication number
- CN108955734B CN108955734B CN201810586323.1A CN201810586323A CN108955734B CN 108955734 B CN108955734 B CN 108955734B CN 201810586323 A CN201810586323 A CN 201810586323A CN 108955734 B CN108955734 B CN 108955734B
- Authority
- CN
- China
- Prior art keywords
- cavity length
- optical fiber
- demodulation
- temperature
- composite sensor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000000034 method Methods 0.000 title claims abstract description 52
- 239000002131 composite material Substances 0.000 title claims abstract description 37
- 239000013307 optical fiber Substances 0.000 title claims abstract description 37
- 238000001228 spectrum Methods 0.000 claims abstract description 61
- 238000004088 simulation Methods 0.000 claims abstract description 16
- 238000007781 pre-processing Methods 0.000 claims abstract description 9
- 230000003595 spectral effect Effects 0.000 claims description 8
- 238000010606 normalization Methods 0.000 claims description 5
- 238000005259 measurement Methods 0.000 abstract description 8
- 230000008569 process Effects 0.000 abstract description 5
- 238000001514 detection method Methods 0.000 abstract description 3
- 238000009776 industrial production Methods 0.000 abstract description 3
- 238000004519 manufacturing process Methods 0.000 abstract description 3
- 230000004044 response Effects 0.000 description 7
- 230000008859 change Effects 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 230000005540 biological transmission Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000005316 response function Methods 0.000 description 2
- 238000012952 Resampling Methods 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 238000004590 computer program Methods 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 230000002708 enhancing effect Effects 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 230000001404 mediated effect Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 230000010363 phase shift Effects 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
Images
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
- G01D5/32—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
- G01D5/35312—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 Fabry Perot
Abstract
The invention provides a cavity length demodulation method of an optical fiber F-P temperature/pressure composite sensor, which comprises the steps of preprocessing a spectrum signal received by the optical fiber F-P temperature/pressure composite sensor, separating the composite cavity length signal by using a band-pass filter, demodulating the spectrum signal by using an FFT (fast Fourier transform) method to estimate a rough cavity length value, constructing a series of virtual interference spectrum signals with different cavity length values and actual interference spectrum signals at large step intervals within a certain range, carrying out cross-correlation demodulation operation to obtain a more accurate cavity length value, reducing a cavity length simulation range according to the cavity length value, carrying out cross-correlation operation at small step intervals within a small range, and repeating the steps in sequence until the demodulation accuracy requirement is met to obtain the cavity length value. The method can be used for absolute measurement of the information of the lengths of the multiple cavities of the optical fiber F-P temperature/pressure composite sensor, has the advantages of high demodulation speed, high cavity length resolution and large dynamic range, and has important practical application value in the aspect of simultaneous detection of high temperature and high pressure in the processes of industrial production, equipment manufacturing and the like.
Description
Technical Field
The invention belongs to the technical field of optical fiber sensing, and relates to a cavity length demodulation method of an optical fiber F-P temperature/pressure composite sensor.
Background
The signal demodulation technology is the core part of the optical fiber F-P sensing system and is the key for determining the precision and stability of the sensing system. The demodulation methods most studied and most widely used at present are classified into two categories, intensity demodulation and phase demodulation. The intensity demodulation directly solves the F-P cavity length through the interference output light intensity, is simple to realize, has high response speed, is easily influenced by the change of the wavelength and the output power of a light source, and has low demodulation precision. Phase demodulation realizes signal demodulation by detecting phase change of interference output spectrum, and has higher precision compared with intensity demodulation.
In the phase demodulation method, a commonly used spectral demodulation method such as a unimodal method or a multimodal method is to perform signal demodulation by tracking a spectral peak in a normalized interference spectrum, and it is difficult to simultaneously perform high-precision and large-dynamic-range measurement. The Fourier transform demodulation method adopts Fast Fourier Transform (FFT) to calculate the frequency spectrum of an output signal, has high response speed, can realize large dynamic range measurement, but has lower demodulation precision. The correlation demodulation method based on cross correlation operation can measure the absolute cavity length value, has high resolution and is suitable for the demodulation range with large cavity length. Other high-precision demodulation methods such as a discrete cavity length demodulation method and the like have slow response, and are not suitable for real-time monitoring of the physical quantity to be detected.
Disclosure of Invention
The invention aims to overcome the defects in the demodulation technology of the optical fiber F-P sensor, provides a quick and high-precision cavity length demodulation method of the optical fiber F-P temperature/pressure composite sensor, and can realize absolute measurement of different cavity length values of the optical fiber F-P composite sensor, thereby realizing quick and high-precision simultaneous measurement of multiple physical quantities.
In order to achieve the above purpose, the invention provides the following technical scheme:
in order to achieve the purpose, the invention adopts the following technical scheme: a cavity length demodulation method of an optical fiber F-P temperature/pressure composite sensor comprises the following steps:
preprocessing a spectrum signal received by the optical fiber F-P temperature/pressure composite sensor;
separating the composite cavity signals by using a band-pass filter;
demodulating the spectrum signal by using Fast Fourier Transform (FFT) to estimate a rough cavity length value;
constructing a plurality of virtual interference spectrum signals with different cavity length values at intervals of a first preset step length in a first specified cavity length simulation range, and performing cross-correlation operation on the virtual interference spectrum signals and actual interference spectrum signals to obtain an accurate cavity length value;
and reducing the simulation range of the first specified cavity length of the cavity length according to the accurate cavity length value, performing cross-correlation operation at intervals of a second step length in a small range, and repeating the steps in sequence until the demodulation precision requirement is met to obtain the cavity length value.
The preprocessing method at least comprises interpolation fitting, denoising and spectrum normalization of the signals.
Wherein the interference spectrum signal formula is expressed as:
a normalized interference spectrum with a cavity length L and an interference contrast of 1 is constructed, expressed as:
in the step of constructing a plurality of virtual interference spectrum signals with different cavity length values and performing cross-correlation operation with the actual interference spectrum signals, the actual interference spectrum signals and the virtual interference spectrum signals are subjected to cross-correlation operation to obtain a correlation coefficient between the actual interference spectrum signals and the virtual interference spectrum signals
Wherein, L, L0Is a real cavity length value and a virtual cavity length value, v is the frequency of the interference light spectrum, v1V and v2Respectively, the lower limit and the upper limit of the spectral frequency of the interference light, c is the speed of light, and gamma is the contrast of the interference fringes.
The method for acquiring the cavity length value comprises the following steps:
when L is equal to L0And then extracting an outer envelope sine curve of the correlation coefficient curve, and obtaining the position of the maximum correlation coefficient according to the maximum value corresponding to the main maximum peak to obtain the real cavity length value to be measured.
After the step of demodulating the spectral signal by using Fast Fourier Transform (FFT) to estimate the rough cavity length value, the method comprises the steps of:
estimation of cavity length value L using Fast Fourier Transform (FFT) demodulationRThen, the cavity length value L is estimatedRTaking 2 to 3 times of Fast Fourier Transform (FFT) resolution as the radius R of the cavity length analog range as the center of the cavity length analog rangeFIn the cavity length analog range (L)R-RF，LR+RF) And performing cross-correlation operation at a first preset step interval.
Compared with the prior art, the invention has the following advantages:
the cavity length demodulation method of the optical fiber F-P temperature/pressure composite sensor utilizes an FFT demodulation method to estimate the cavity length, and then utilizes a variable step size cross-correlation method to accurately solve the cavity length, so that the demodulation efficiency can be greatly improved on the premise of ensuring high-precision cavity length demodulation; the method can be used for absolute measurement of multi-cavity long information of the optical fiber F-P composite sensor, has the advantages of high demodulation speed, high cavity length resolution and large dynamic range, and has important practical application value in the aspect of simultaneous detection of high temperature and high pressure in the processes of industrial production, equipment manufacturing and the like.
Drawings
FIG. 1 is a schematic flow chart of a cavity length demodulation method of an optical fiber F-P temperature/pressure composite sensor provided by the invention;
FIG. 2 is a logic diagram of a cavity length demodulation method of the fiber F-P temperature/pressure composite sensor provided by the invention;
fig. 3 is a schematic structural diagram of a cavity length demodulation system of an optical fiber F-P temperature/pressure composite sensor provided by the invention.
Detailed Description
The technical solution of the present invention will be further described in more detail with reference to the following embodiments. It is to be understood that the described embodiments are merely a few embodiments of the invention, and not all embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, shall fall within the scope of protection of the present invention.
Referring to fig. 1 and 2, fig. 1 and 2 are a schematic flow chart and a schematic logic diagram of a cavity length demodulation method of an optical fiber F-P temperature/pressure composite sensor according to the present invention. The method comprises the following steps:
s1: and preprocessing the spectral signals received by the optical fiber F-P temperature/pressure composite sensor.
The spectrum signal received by the optical fiber F-P temperature/pressure composite sensor is preprocessed, and the preprocessing comprises interpolation fitting, denoising and spectrum normalization of the signal. Specifically, the method comprises the steps of carrying out cubic spline interpolation fitting on discrete signals to realize data resampling; performing wavelet transformation to realize multi-scale decomposition on the spectrum signals, separating the signals to respectively obtain wavelet coefficients of effective signals and noise signals, enhancing the wavelet coefficients of the effective signals, reconstructing the effective signals and improving the signal-to-noise ratio; the Hilbert transform is carried out on the spectrum signal, so that the amplitude of each frequency component in a frequency domain is kept unchanged, but 90-degree phase shift is generated, the signal envelope is extracted, and the purpose of spectrum normalization is achieved.
S2: the composite cavity signal is separated using a band pass filter.
And after the preprocessing is finished, selecting a Hamming window to design a window function of the band-pass filter.
For an ideal low-pass linear phase digital filter, the ideal frequency response function can be expressed as:
corresponding to a unit impulse response of
Approximating h by a finite-length unit impulse response h (n)d(n) of (a). Using window function w (n) to convert hd(n) truncating and performing weighting to obtain:
h(n)＝hd(n)·w(n)
h (n) is the unit impulse response sequence of the actually designed FIR digital filter, the frequency response function of which is H (e)jw) Is composed of
Where n is the length of the selected window function w (n).
And selecting the type of a proper window function w (N) and the value of the window length N according to the requirements on the minimum attenuation of the stop band and the width of the transition band. After selecting window type and window length N, the unit impulse response sum H (e) is obtainedjw) And checking whether the requirements are met or not. If H (e)jw) And if the requirement is not met, the length N is required to be reset, and checking calculation is carried out again until the requirement is met.
S3: the spectral signal is demodulated using Fast Fourier Transform (FFT) to estimate a coarse cavity length value.
After the step of demodulating the spectral signal by Fast Fourier Transform (FFT) to estimate the coarse cavity length value, the method comprises the steps of:
estimation of cavity length value L using Fast Fourier Transform (FFT) demodulationRThen, the cavity length value L is estimatedRTaking 2 to 3 times of Fast Fourier Transform (FFT) resolution as the radius R of the cavity length analog range as the center of the cavity length analog rangeFIn the cavity length analog range (L)R-RF，LR+RF) And performing cross-correlation operation at a first preset step interval.
S4: and constructing a plurality of virtual interference spectrum signals with different cavity length values at a first preset step length interval in a first appointed cavity length simulation range, and performing cross-correlation operation on the virtual interference spectrum signals and actual interference spectrum signals to obtain an accurate cavity length value.
For single cavity signals, the interference spectrum signals are:
a normalized interference spectrum with a cavity length L and an interference contrast of 1 is constructed, expressed as:
obtaining a correlation coefficient between an interference signal corresponding to the real cavity length to be measured and an interference signal corresponding to the virtual structure cavity length:
therefore, when L ═ L0And then, when the real cavity length is equal to the virtual cavity length, the correlation coefficient C obtains the maximum value. And extracting an outer envelope sine curve of the correlation coefficient curve, and obtaining the position of the maximum correlation coefficient according to the maximum value corresponding to the main maximum peak so as to obtain the real cavity length value to be measured.
S5: and reducing the simulation range of the first specified cavity length of the cavity length according to the accurate cavity length value, performing cross-correlation demodulation operation at intervals of a second step length in a small range, and repeating the operations in sequence until the demodulation precision requirement is met to obtain the cavity length value.
The method of the invention is to perform cross-correlation operation on a virtual spectrum signal with a certain cavity length interval and an actual spectrum so as to obtain the cavity length value of the optical fiber F-P sensor, the cavity length interval needs to be set to be smaller in order to obtain high demodulation precision and resolution, if a rough cavity length value of a sensor to be measured cannot be determined, a larger cavity length virtual range needs to be set, and the corresponding calculated amount is increased rapidly. The cavity length value L can thus be estimated using Fast Fourier Transform (FFT) demodulationRThen, the rough measurement value L is measuredRTaking 2 to 3 times of the resolution of the FFT method as the radius L of the cavity length simulation range as the center of the cavity length simulation rangeRIn the cavity length analog range (L)R-RF，LR+RF) And then, reducing the cavity length simulation range according to the cavity length value, performing the cross-correlation operation at small step intervals in a small range, and repeating the operations in sequence until the demodulation precision requirement is met to obtain the final cavity length value to be detected.
As shown in fig. 3, the present invention provides a demodulation system of an optical fiber F-P temperature/pressure sensor, which is mediated by the method in the foregoing technical solution, including: the demodulation system comprises a broadband light source 1, a circulator 2, a transmission optical fiber 3, an optical fiber F-P pressure/temperature composite sensor 4, a photoelectric detector 5 and a computer 6, wherein light emitted by the broadband light source 1 is transmitted to the composite sensor 4 through the coupler 2 and the transmission optical fiber 3, reflected interference signal light is detected by the photoelectric detector 5 and then transmitted to the computer 6 for operation, and the computer 6 processes data in real time according to a computer program written by the demodulation method provided by the invention and demodulates the data to obtain the cavity length change of the sensor 4 to be detected. The center wavelength of the broadband light source 1 is 850nm, and the 3dB bandwidth is 40 nm.
The length values of the temperature cavity and the pressure cavity of the optical fiber F-P pressure/temperature composite sensor are respectively 300 mu m and 100 mu m. And preprocessing the spectrum signals received by the sensor, including interpolation fitting, denoising and spectrum normalization of the signals. And separating the preprocessed signals by using a band-pass filter. Demodulating the separated spectrum containing pressure cavity length information: and performing cross-correlation operation after estimating the cavity length by using an FFT method to determine the cavity length simulation range. Firstly, performing cross-correlation operation within the range of 80-120 mu m at the cavity length interval of 100nm to obtain the cavity length of 99.7 mu m; the last demodulation result is used as a range center, the cavity length resolution is enlarged by ten times to be used as a range radius, the cavity length simulation range is determined to be 98 mu m-102 mu m again, then the cavity length interval of 10nm is used for carrying out cross-correlation operation in the range, and the cavity length is demodulated to be 100.12 mu m; re-determining the cavity length simulation range in the same way as the last time, and then performing cross-correlation operation at the cavity length interval of 1nm in the range of 99.9-100.3 mu m to demodulate the cavity length of 100.121 mu m; finally, cross-correlation operation is carried out within the range of 100.1-100.14 mu m by taking the target cavity length resolution of 0.1nm as the cavity length interval, the final pressure cavity length value is demodulated to be 100.1212 mu m, and the cavity length resolution reaches 0.1 nm. Similarly, the separated spectrum containing the temperature cavity length information is demodulated, the final temperature cavity length value is 299.9103 μm, and the cavity length resolution also reaches 0.1 nm.
Compared with the prior art, the invention has the following advantages:
the cavity length demodulation method of the optical fiber F-P temperature/pressure composite sensor utilizes an FFT demodulation method to estimate the cavity length, and then utilizes a variable step size cross-correlation method to accurately solve the cavity length, so that the demodulation efficiency can be greatly improved on the premise of ensuring high-precision cavity length demodulation; the method can be used for absolute measurement of multi-cavity long information of the optical fiber F-P composite sensor, has the advantages of high demodulation speed, high cavity length resolution and large dynamic range, and has important practical application value in the aspect of simultaneous detection of high temperature and high pressure in the processes of industrial production, equipment manufacturing and the like.
The above description is only an embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes performed by the present specification and drawings, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.
Claims (6)
1. A cavity length demodulation method of an optical fiber F-P temperature/pressure composite sensor is characterized by comprising the following steps: the method comprises the following steps:
preprocessing a spectrum signal received by the optical fiber F-P temperature/pressure composite sensor;
separating the composite cavity signals by using a band-pass filter;
demodulating the spectrum signal by using Fast Fourier Transform (FFT) to estimate a rough cavity length value;
constructing a plurality of virtual interference spectrum signals with different cavity length values at a first preset step length interval in a first appointed cavity length simulation range, and performing cross-correlation demodulation operation on the virtual interference spectrum signals and actual interference spectrum signals to obtain an accurate cavity length value;
and reducing the simulation range of the first specified cavity length of the cavity length according to the accurate cavity length value, performing cross-correlation demodulation operation at intervals of a second step length in a small range, and repeating the operations in sequence until the demodulation precision requirement is met to obtain the cavity length value.
2. The cavity length demodulation method of the optical fiber F-P temperature/pressure composite sensor according to claim 1, characterized in that: the mode of preprocessing the received spectrum signal at least comprises interpolation fitting, denoising and spectrum normalization of the signal, and the optical fiber F-P temperature/pressure composite sensor is an optical fiber sensor with 2F-P cavities formed by 3 reflecting surfaces.
3. The cavity length demodulation method of the optical fiber F-P temperature/pressure composite sensor according to claim 1, characterized in that: the interference spectrum signal refers to any 1 of 2 spectrum signals containing different cavity length information after the interference spectrum of the composite sensor is processed by a band-pass filter;
the interference spectrum signal is formulated as:
a normalized interference spectrum with a cavity length L and an interference contrast of 1 is constructed, expressed as:
wherein, ν is the frequency of the interference light spectrum, c is the speed of light, and γ is the interference fringe contrast.
4. The cavity length demodulation method of the optical fiber F-P temperature/pressure composite sensor according to claim 1, characterized in that: in the step of constructing a plurality of virtual interference spectrum signals with different cavity length values and performing cross-correlation operation with the actual interference spectrum signals, the actual interference spectrum signals and the virtual interference spectrum signals are subjected to cross-correlation operation to obtain a correlation coefficient between the actual interference spectrum signals and the virtual interference spectrum signals
Wherein, L, L0Is a real cavity length value and a virtual cavity length value, v is the frequency of the interference light spectrum, v1V and v2Respectively, the lower limit and the upper limit of the spectrum frequency of the interference light, c is the light speed, and gamma is the contrast of the interference fringes; the actual interference spectrum signal refers to any 1 of 2 spectrum signals containing different cavity length information after the interference spectrum of the composite sensor is processed by a band-pass filter.
5. The cavity length demodulation method of the optical fiber F-P temperature/pressure composite sensor according to claim 4, characterized in that: the step of obtaining the cavity length value is as follows:
when L is equal to L0And then extracting an outer envelope sine curve of the correlation coefficient curve, and obtaining the position of the maximum correlation coefficient according to the maximum value corresponding to the main maximum peak to obtain the real cavity length value to be measured.
6. The cavity length demodulation method of the optical fiber F-P temperature/pressure composite sensor according to claim 1, characterized in that: after the step of demodulating the spectral signal by Fast Fourier Transform (FFT) to estimate the coarse cavity length value, the method comprises the steps of:
estimation of cavity length value L using Fast Fourier Transform (FFT) demodulationRThen, the cavity length value L is estimatedRTaking 2 to 3 times of Fast Fourier Transform (FFT) resolution as the radius R of the cavity length analog range as the center of the cavity length analog rangeFIn the cavity length analog range (L)R-RF，LR+RF) Performing cross-correlation operation at a first preset step interval;
and after the first cross-correlation operation is finished, reducing the simulation range of the first specified cavity length to obtain a second cavity length simulation range, simultaneously reducing the first preset step interval to obtain a second step interval, performing the second cross-correlation operation at the second step interval in the second cavity length simulation range, and repeating the steps in sequence until the demodulation precision requirement is met to obtain a final cavity length value.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810586323.1A CN108955734B (en) | 2018-06-08 | 2018-06-08 | Cavity length demodulation method of optical fiber F-P temperature/pressure composite sensor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810586323.1A CN108955734B (en) | 2018-06-08 | 2018-06-08 | Cavity length demodulation method of optical fiber F-P temperature/pressure composite sensor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108955734A CN108955734A (en) | 2018-12-07 |
| CN108955734B true CN108955734B (en) | 2020-05-05 |
Family
ID=64493861
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810586323.1A Active CN108955734B (en) | 2018-06-08 | 2018-06-08 | Cavity length demodulation method of optical fiber F-P temperature/pressure composite sensor |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108955734B (en) |
Families Citing this family (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109342907B (en) * | 2018-12-13 | 2021-01-05 | 武汉理工大学 | Optical fiber sensor structure for partial discharge of transformer, demodulation method and monitoring method |
| CN109916434B (en) * | 2019-03-26 | 2021-04-06 | 西安工业大学 | Optical fiber Fabry-Perot sensor cavity length multiple frequency related demodulation method |
| CN110595516B (en) * | 2019-09-18 | 2020-12-18 | 华中科技大学 | FPI cavity length demodulation method and system |
| CN111998884B (en) * | 2020-07-14 | 2023-05-26 | 重庆邮电大学 | Demodulation method of wavelength self-calibration optical fiber FP sensor |
| CN111707303A (en) * | 2020-07-17 | 2020-09-25 | 武汉理工大学 | Variable-step-length rapid high-precision signal demodulation method for optical fiber F-P sensor |
| CN111707304A (en) * | 2020-07-29 | 2020-09-25 | 武汉理工大学 | Method for rapidly demodulating discrete cavity length of variable-step-length optical fiber F-P sensor |
| CN112050942B (en) * | 2020-07-30 | 2021-06-15 | 东北大学 | Optical fiber interference spectrum cavity length correction method based on phase compensation |
| CN112880569B (en) * | 2021-01-25 | 2022-11-08 | 上海大学 | Multi-surface measurement method based on cavity length correction |
| CN113790743B (en) * | 2021-07-30 | 2023-04-25 | 中交第二航务工程局有限公司 | Wavelength demodulation algorithm for fiber grating sensing system |
| CN117686009A (en) * | 2024-02-04 | 2024-03-12 | 武汉理工大学 | Optical fiber double-FP composite sensing monitoring equipment |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100445697C (en) * | 2006-03-21 | 2008-12-24 | 大连理工大学 | Cavity length demodulating algorithm of fibre-optical F-P sensor |
| CN103697923A (en) * | 2013-12-20 | 2014-04-02 | 北京航空航天大学 | Method for demodulating extrinsic fiber Fabry-Perot interferometer cavity length |
| CN203642944U (en) * | 2014-01-09 | 2014-06-11 | 中国人民解放军总参谋部工程兵科研三所 | High-speed demodulation system of optical fiber F-P chamber sensor |
| CN106643835B (en) * | 2015-11-03 | 2019-07-05 | 中国石油天然气股份有限公司 | Fabry-perot optical fiber chamber demodulation method and device and Fabry-perot optical fiber interferometer |
| CN106017522B (en) * | 2016-05-11 | 2018-09-14 | 武汉理工大学 | A kind of quick high accuracy signal demodulating method of fibre-optical F-P sensor |
| CN105973282B (en) * | 2016-05-20 | 2018-10-09 | 武汉理工大学 | The long Wavelet Phase of fibre-optical F-P sensor chamber extracts demodulation method |
-
2018
- 2018-06-08 CN CN201810586323.1A patent/CN108955734B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN108955734A (en) | 2018-12-07 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108955734B (en) | Cavity length demodulation method of optical fiber F-P temperature/pressure composite sensor | |
| CN108534811B (en) | Cavity length demodulation algorithm of short-cavity optical fiber Fabry-Perot sensor | |
| CN107402082B (en) | Brillouin scattering signal processing method and distributed optical fiber sensing system thereof | |
| CN112097813B (en) | 3X 3 coupler photoelectric detection method and device based on optical frequency modulation | |
| CN105973282B (en) | The long Wavelet Phase of fibre-optical F-P sensor chamber extracts demodulation method | |
| CN103487074B (en) | Utilize the method for 3 peak-seeking algorithm process FBG transducing signals | |
| CN107490397B (en) | High-accuracy self-adaptation filters the quick Peak Search Method of FBG spectrum | |
| CN112985639B (en) | Distributed optical fiber sensing method based on chirp removal and time domain sub-chirp pulse extraction | |
| CN108709574B (en) | Fiber grating sensing system for wavelet singularity detection | |
| CN109916434B (en) | Optical fiber Fabry-Perot sensor cavity length multiple frequency related demodulation method | |
| CN106017522A (en) | Rapid high-precision signal demodulation method of fiber F-P sensor | |
| CN108225385A (en) | A kind of overlapping FBG transducing signal peak value localization methods | |
| CN103940363A (en) | High-precision optical fiber strain low-frequency sensing demodulation method based on wavelet cross-correlation technology | |
| CN105181152A (en) | Calculation method for frequency shift of distributed Brillouin scattered spectrum | |
| CN210567574U (en) | Oil and gas pipeline leakage monitoring system based on optical fiber | |
| CN103335600B (en) | Ratio Fringe-counting method and displacement transducer demodulating system thereof based on dual F-P interferometer system | |
| CN103412189B (en) | Information filtering demodulation method for electrical tomography system | |
| CN110793557B (en) | Cavity length demodulation method for short-cavity optical fiber Fabry-Perot sensor | |
| CN108426594B (en) | Fiber grating reflection spectrum demodulation system of correlation algorithm | |
| CN110333506B (en) | Method for extracting inhaul cable position parameters of cable force measurement radar | |
| CN111707303A (en) | Variable-step-length rapid high-precision signal demodulation method for optical fiber F-P sensor | |
| CN113790743B (en) | Wavelength demodulation algorithm for fiber grating sensing system | |
| CN111707304A (en) | Method for rapidly demodulating discrete cavity length of variable-step-length optical fiber F-P sensor | |
| CN103398799A (en) | Fabry-Perot interference ring image processing method | |
| CN112268608A (en) | High-precision demodulation algorithm for strong interference DVS |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |