CN111707304A - Method for rapidly demodulating discrete cavity length of variable-step-length optical fiber F-P sensor - Google Patents
Method for rapidly demodulating discrete cavity length of variable-step-length optical fiber F-P sensor Download PDFInfo
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- 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 relates to a method for quickly demodulating the discrete cavity length of a variable-step-length optical fiber F-P sensor. The method combines an FFT demodulation method and a DGT demodulation method, and adds a step length changing idea to form a step length changing fast fiber F-P sensor discrete cavity length demodulation method. The method can realize high-precision demodulation of the cavity length, greatly reduces the calculation amount of directly carrying out searching operation with target resolution, realizes quick high-precision solving of the cavity length of the optical fiber F-P sensor, improves the demodulation rate, and realizes high-precision and high-efficiency demodulation.
Description
Technical Field
The invention relates to the technical field of optical fiber sensing, in particular to a method for quickly demodulating discrete cavity length of a variable-step-length optical fiber F-P sensor.
Background
At present, an intensity demodulation method and a phase demodulation method are the most common demodulation methods of the optical fiber F-P sensor. The intensity demodulation method generally adopts a single-wavelength light source to demodulate the spectrum signal by detecting the light intensity, has high response speed and simple demodulation system structure, and is suitable for measuring dynamic signals such as sound waves, vibration and the like. The phase demodulation method generally adopts a sweep frequency light source or a broadband light source, carries out spectrum signal demodulation according to the relation between the cavity length and the phase, has high demodulation precision and low response speed, and is suitable for measuring static signals of temperature, pressure, strain and the like. In the practical application process of the intensity demodulation method, the light intensity is affected due to external environmental factors, component loss and the like. The light source in the system is often interfered by factors such as the temperature in the external environment, and the like, so that the measurement precision and the stability of the whole optical fiber sensing system are reduced. Aiming at the defects of the traditional intensity demodulation method, a plurality of scholars at home and abroad research various methods to solve the problem of influence of external interference on the system. For example, Zhang Gui Ju et al, the university of the major continuum engineering, proposed a self-compensating intensity demodulation method, which adopts a broadband light source to replace a monochromatic laser light source, and reduces the interference influence degree of the external environment on the system. The phase demodulation method is to solve the cavity length based on the phase difference of the interference spectrum output by the whole F-P cavity. Compared with intensity demodulation, the method has higher demodulation precision and stability and large dynamic measurement range. However, the phase demodulation method is slow in response speed due to a large amount of calculation, and is generally applied to measurement of static parameters such as temperature and pressure. Therefore, in the commonly used optical fiber F-P demodulation algorithm, the algorithm with high response speed is often low in demodulation precision, and the high-precision demodulation algorithm is large in calculation amount and low in efficiency.
At present, the cavity length demodulation method of the optical fiber F-P sensor comprises the following steps:
1. the cavity length demodulation method of the optical fiber F-P cavity introduced in the Chinese patent (patent No. 201310711338.3) 'a method for demodulating extrinsic optical fiber Fabry-Perot cavity length' obtains the cavity length solution of the F-P cavity by using a multi-wavelength intensity demodulation method, and the demodulation method is more accurate than the traditional optical fiber F-P cavity intensity demodulation method, and the measurement precision can reach 0.1 um. However, this method has a slow response speed, a large amount of calculation, and low demodulation efficiency.
The demodulation methods of the optical fiber F-P sensor are mainly divided into an intensity demodulation method and a phase demodulation method, and other methods are mostly extensions of the two methods. The existing demodulation method has the disadvantages of low algorithm precision with high response speed, large calculation amount and low efficiency of the high-precision demodulation algorithm. Therefore, it is necessary to improve the conventional method, reduce the amount of demodulation operation, increase the demodulation rate, and realize high-precision and high-efficiency demodulation while maintaining high-precision demodulation.
Disclosure of Invention
Aiming at the defects of the existing method, a method for rapidly demodulating the discrete cavity length of the variable-step-length optical fiber F-P sensor is provided.
The technical scheme adopted by the invention for solving the technical problems is as follows: a method for quickly demodulating discrete cavity length of a variable-step-length optical fiber F-P sensor is constructed, and comprises the following steps:
spectrum preprocessing, wherein the preprocessing mode comprises wavelet threshold denoising and interpolation processing on signals;
acquiring a frequency domain spectrum by utilizing Fourier transform, and designing a band-pass filter to extract and separate signals;
aiming at the obtained frequency domain spectrum, a fast Fourier transform algorithm is adopted to obtain a pre-estimated value of the cavity length of the optical fiber F-P sensor;
taking the estimated value of the cavity length of the optical fiber F-P sensor as the center of a cavity length range, and performing discrete cavity length calculation in a cavity length simulation range at set step intervals, wherein the position corresponding to the maximum DGT coefficient is the cavity length value of the optical fiber F-P sensor; and gradually reducing the step interval magnitude, carrying out DGT operation in a small cavity length range, and repeating the process until the cavity length value of the optical fiber F-P sensor with the required precision is obtained.
In the step of spectrum preprocessing, a wavelet threshold denoising method is adopted to remove Gaussian white noise which is often mixed in interference spectrum signals.
The wavelet threshold denoising method adopts a soft threshold function, and the specific threshold selection basis
Where n represents the number of data for the spectral signal and represents the standard deviation of the noise signal. In the step of spectrum preprocessing, the adopted interpolation processing method is a cubic spline interpolation method, and invalid points generated by wavelet threshold denoising are repaired by adopting the interpolation method, so that the spectrum signals are more complete and smooth.
In the step of designing the band-pass filter to extract and separate the signals, the designed band-pass filter is an FIR filter.
In the step of obtaining the estimated value of the cavity length of the optical fiber F-P sensor by adopting a fast Fourier transform algorithm, the FFT demodulation algorithm is to perform FFT conversion processing on the obtained reflection spectrum signal, obtain a frequency component containing cavity length information by filtering, and then perform frequency spectrum analysis on the frequency component to further obtain the cavity length value of the optical fiber F-P sensor.
The method comprises the following steps of carrying out a variable-step-length fast discrete cavity length demodulation algorithm on a preprocessed spectrum signal, wherein the detailed steps are as follows:
acquiring a cavity length estimated value of the optical fiber F-P sensor by adopting a fast Fourier algorithm;
carrying out discrete cavity length demodulation processing with a larger step length in a large range to obtain a smaller cavity length simulation range containing an actual cavity length value;
reducing the step length, and demodulating the discrete cavity length in a smaller cavity length simulation range to obtain a smaller cavity length simulation range;
the process is repeated until the required demodulation precision is achieved, and the cavity length value of the high-precision optical fiber F-P sensor is obtained.
The invention is different from the prior art, and provides a method for quickly demodulating the discrete cavity length of a variable-step-length optical fiber F-P sensor. The method combines an FFT demodulation method and a DGT demodulation method, and adds a step length changing idea to form a step length changing fast fiber F-P sensor discrete cavity length demodulation method. The method can realize high-precision demodulation of the cavity length, greatly reduces the calculation amount of directly carrying out searching operation with target resolution, realizes quick high-precision solving of the cavity length of the optical fiber F-P sensor, improves the demodulation rate, and realizes high-precision and high-efficiency demodulation.
Drawings
The invention will be further described with reference to the accompanying drawings and examples, in which:
fig. 1 is a schematic flow chart of a method for rapidly demodulating discrete cavity length of a variable-step optical fiber F-P sensor provided by the invention.
FIG. 2 is a schematic flow logic diagram of a discrete cavity length fast demodulation method for a variable-step fiber F-P sensor provided by the invention.
Detailed Description
For a more clear understanding of the technical features, objects and effects of the present invention, embodiments of the present invention will now be described in detail with reference to the accompanying drawings.
Referring to fig. 1, the invention provides a method for rapidly demodulating discrete cavity length of a variable-step optical fiber F-P sensor, comprising the following steps:
spectrum preprocessing, wherein the preprocessing mode comprises wavelet threshold denoising and interpolation processing on signals; acquiring a frequency domain spectrum by utilizing Fourier transform, and designing a band-pass filter to extract and separate signals;
aiming at the obtained frequency domain spectrum, a fast Fourier transform algorithm is adopted to obtain a pre-estimated value of the cavity length of the optical fiber F-P sensor;
taking the estimated value of the cavity length of the optical fiber F-P sensor as the center of a cavity length range, and performing discrete cavity length calculation in a cavity length simulation range at set step intervals, wherein the position corresponding to the maximum DGT coefficient is the cavity length value of the cavity length of the optical fiber F-P sensor; and gradually reducing the step interval magnitude, carrying out DGT operation in a small cavity length range, and repeating the process until the cavity length value of the optical fiber F-P sensor with the required precision is obtained.
In the step of spectrum preprocessing, a wavelet threshold denoising method is adopted to remove Gaussian white noise which is often mixed in interference spectrum signals.
The wavelet threshold denoising method adopts a soft threshold function, and a specific threshold selection basis represents the data number of the spectral signals and the standard deviation of the noise signals.
In the step of spectrum preprocessing, the adopted interpolation processing method is a cubic spline interpolation method, and invalid points generated by wavelet threshold denoising are repaired by adopting the interpolation method, so that the spectrum signals are more complete and smooth.
In the step of designing the band-pass filter to extract and separate the signals, the designed band-pass filter is an FIR filter. The FIR filter can be designed directly according to frequency, not only can meet the requirement of amplitude characteristic, but also can realize linear phase characteristic, has good stability and can realize the design of a multi-passband filter system.
In the step of obtaining the estimated value of the cavity length of the optical fiber F-P sensor by adopting a fast Fourier transform algorithm, the FFT demodulation algorithm is to perform FFT conversion processing on the obtained reflection spectrum signal, obtain a frequency component containing cavity length information by filtering, and then perform frequency spectrum analysis on the frequency component to further obtain the cavity length value of the optical fiber F-P sensor. The FFT demodulation algorithm has high demodulation speed but low measurement precision, and the obtained cavity length value has large deviation from the actual cavity length value and does not meet the precision requirement, so the cavity length value obtained by the algorithm is used as a pre-estimated value for processing.
The variable step fast discrete cavity length demodulation algorithm takes a cavity length estimated value as the center of a cavity length range, and the radius of the search range is generally 2-3 times of the accuracy of the FFT algorithm. And then, discrete cavity length calculation is carried out within a cavity length simulation range at certain step length intervals, and the position corresponding to the maximum DGT coefficient is the cavity length value. And then gradually reducing the step interval magnitude, carrying out DGT operation in a smaller cavity length range, and repeating the process until a cavity length value with required precision is obtained.
The method comprises the following steps of carrying out a variable-step-length fast discrete cavity length demodulation algorithm on a preprocessed spectrum signal, wherein the detailed steps are as follows:
acquiring a cavity length estimated value of the optical fiber F-P sensor by adopting a fast Fourier algorithm;
carrying out discrete cavity length demodulation processing with large step length in a large range to obtain a small cavity length simulation range containing the actual cavity length value of the optical fiber F-P sensor;
reducing the step length, and demodulating the discrete cavity length within a small cavity length analog range to obtain a cavity length analog range of a smaller range;
the process is repeated until the required demodulation precision is achieved, and the cavity length value of the high-precision optical fiber F-P sensor is obtained.
In the implementation, an optical fiber F-P sensor with a cavity length of about 170 μm, i.e., an estimated value of 170 μm, was selected for experimental study according to the procedure shown in FIG. 2. The initial cavity length range is 160-180 mu m, discrete cavity length calculation is carried out within the range at step length intervals of 100nm for 200 times, and the corresponding cavity length is 170.7 mu m; then, with 170.7 μm as the range center, the simulation cavity length range is 169.7 μm-171.7 μm, the step search interval is 10nm, and the operation is totally carried out for 200 times to obtain the cavity length value of 170.75 μm; similarly, with 170.75 μm as the center, the simulated cavity length range is set to 170.65 μm-170.85 μm, and the cavity length value is 170.756 μm after 200 times of search and operation with the step length of 1 nm; and finally, performing 200 times of operation within the range of 170.746-170.766 microns by step length of 0.1nm to obtain a cavity length value of 170.7564 microns.
In the whole variable-step discrete cavity length demodulation algorithm, the operation is carried out for 800 times in total, so that the cavity length resolution reaches 0.1 nm. If the calculation is performed directly in the range of 160 μm to 180 μm with a resolution of 0.1nm, 200000 is required. Therefore, the improved variable-step discrete cavity length demodulation algorithm realizes high-precision demodulation of the cavity length, greatly reduces the calculation amount of directly carrying out search operation with the target resolution, improves the demodulation efficiency and realizes quick high-precision demodulation of the F-P cavity.
The invention provides a method for quickly demodulating discrete cavity length of a variable-step optical fiber F-P sensor, which is different from the prior art. The method combines an FFT demodulation method and a DGT demodulation method, and adds a step length changing idea to form a step length changing optical fiber F-P sensor discrete cavity length fast demodulation method. The method can realize high-precision demodulation of the cavity length, greatly reduces the calculation amount of directly carrying out searching operation with target resolution, realizes quick high-precision solving of the cavity length of the optical fiber F-P sensor, improves the demodulation rate, and realizes high-precision and high-efficiency demodulation.
While the present invention has been described with reference to the embodiments shown in the drawings, the present invention is not limited to the embodiments, which are illustrative and not restrictive, and it will be apparent to those skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope of the invention as defined in the appended claims.
Claims (7)
1. A method for rapidly demodulating discrete cavity length of a variable-step optical fiber F-P sensor is characterized by comprising the following steps:
spectrum preprocessing, wherein the preprocessing mode comprises wavelet threshold denoising and interpolation processing on signals;
acquiring a frequency domain spectrum by utilizing Fourier transform, and designing a band-pass filter to extract and separate signals;
aiming at the obtained frequency domain spectrum, a fast Fourier transform algorithm is adopted to obtain a pre-estimated value of the cavity length of the optical fiber F-P sensor;
taking the cavity length estimated value of the optical fiber F-P sensor as the center of a cavity length range, and performing discrete cavity length calculation in a cavity length simulation range at set step intervals, wherein the position corresponding to the maximum DGT coefficient is the cavity length value of the optical fiber F-P sensor; and gradually reducing the step interval magnitude, carrying out DGT operation in a small cavity length range, and repeating the process until the cavity length value of the optical fiber F-P sensor with the required precision is obtained.
2. The method as claimed in claim 1, wherein in the step of spectrum preprocessing, a wavelet threshold denoising method is used to remove the gaussian white noise often included in the interference spectrum signal.
3. The method for rapidly demodulating discrete cavity length of variable-step optical fiber F-P sensor according to claim 2, wherein the wavelet threshold denoising method employs a soft threshold function, and the specific threshold selection basis
Where n represents the number of data for the spectral signal and represents the standard deviation of the noise signal.
4. The method for rapidly demodulating the discrete cavity length of the variable-step optical fiber F-P sensor according to claim 1, wherein in the step of spectrum preprocessing, the adopted interpolation processing method is a cubic spline interpolation method, and invalid points generated by wavelet threshold denoising are repaired by adopting the interpolation method, so that the spectrum signals are more complete and smooth.
5. The method for rapidly demodulating discrete cavity length of variable-step fiber F-P sensor according to claim 1, wherein in the step of designing the band-pass filter to extract and separate the signal, the designed band-pass filter is an FIR filter.
6. The method as claimed in claim 1, wherein in the step of obtaining the estimated value of the cavity length of the fiber F-P sensor by using the fast fourier transform algorithm, the FFT demodulation algorithm is to perform FFT processing on the obtained reflection spectrum signal, obtain frequency components containing cavity length information by filtering, and then perform spectral analysis on the frequency components to obtain the estimated value of the cavity length of the fiber F-P sensor.
7. The discrete cavity length fast demodulation method of the variable-step optical fiber F-P sensor according to claim 1, characterized in that a variable-step fast discrete cavity length demodulation algorithm is performed for the preprocessed spectral signals, and the detailed steps are as follows:
acquiring a cavity length estimated value of the optical fiber F-P sensor by adopting a fast Fourier algorithm;
carrying out discrete cavity length demodulation processing in a large range by using a large step length to obtain a small cavity length simulation range containing the actual cavity length value of the optical fiber F-P sensor;
reducing the step length, and demodulating the discrete cavity length in a smaller cavity length analog range to obtain a smaller cavity length range;
the process is repeated until the required demodulation precision is achieved, and the cavity length value of the high-precision optical fiber F-P sensor can be obtained.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117686009A (en) * | 2024-02-04 | 2024-03-12 | 武汉理工大学 | Optical fiber double-FP composite sensing monitoring equipment |
| CN117686009B (en) * | 2024-02-04 | 2024-05-14 | 武汉理工大学 | Optical fiber double-FP composite sensing monitoring equipment |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105973282A (en) * | 2016-05-20 | 2016-09-28 | 武汉理工大学 | Fiber F-P sensor cavity length wavelet phase extraction demodulation method |
| CN106017522A (en) * | 2016-05-11 | 2016-10-12 | 武汉理工大学 | Rapid high-precision signal demodulation method of fiber F-P sensor |
| CN107101813A (en) * | 2017-04-26 | 2017-08-29 | 河北工业大学 | A kind of frame-type circuit breaker mechanical breakdown degree assessment method based on vibration signal |
| CN108955734A (en) * | 2018-06-08 | 2018-12-07 | 武汉理工大学 | A kind of cavity length demodulating method of fiber F-P temperature/pressure compound sensor |
| WO2019029193A1 (en) * | 2017-08-08 | 2019-02-14 | 江苏弘开传感科技有限公司 | Cavity length measurement device for microwave resonant cavity and sensor |
-
2020
- 2020-07-29 CN CN202010742565.2A patent/CN111707304A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106017522A (en) * | 2016-05-11 | 2016-10-12 | 武汉理工大学 | Rapid high-precision signal demodulation method of fiber F-P sensor |
| CN105973282A (en) * | 2016-05-20 | 2016-09-28 | 武汉理工大学 | Fiber F-P sensor cavity length wavelet phase extraction demodulation method |
| CN107101813A (en) * | 2017-04-26 | 2017-08-29 | 河北工业大学 | A kind of frame-type circuit breaker mechanical breakdown degree assessment method based on vibration signal |
| WO2019029193A1 (en) * | 2017-08-08 | 2019-02-14 | 江苏弘开传感科技有限公司 | Cavity length measurement device for microwave resonant cavity and sensor |
| CN108955734A (en) * | 2018-06-08 | 2018-12-07 | 武汉理工大学 | A kind of cavity length demodulating method of fiber F-P temperature/pressure compound sensor |
Non-Patent Citations (1)
| Title |
|---|
| 雷小华 等: "基于三次样条插值的光纤F_P传感器傅里叶变换解调研究", 《光子学报》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117686009A (en) * | 2024-02-04 | 2024-03-12 | 武汉理工大学 | Optical fiber double-FP composite sensing monitoring equipment |
| CN117686009B (en) * | 2024-02-04 | 2024-05-14 | 武汉理工大学 | Optical fiber double-FP composite sensing monitoring equipment |
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Application publication date: 20200925 |