CN113553997A - Signal processing method, storage medium and system for jointly improving wavelet threshold - Google Patents

Signal processing method, storage medium and system for jointly improving wavelet threshold Download PDF

Info

Publication number
CN113553997A
CN113553997A CN202111092643.XA CN202111092643A CN113553997A CN 113553997 A CN113553997 A CN 113553997A CN 202111092643 A CN202111092643 A CN 202111092643A CN 113553997 A CN113553997 A CN 113553997A
Authority
CN
China
Prior art keywords
wavelet
signal
threshold
noise
processing
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.)
Pending
Application number
CN202111092643.XA
Other languages
Chinese (zh)
Inventor
曹栋
毕研钊
郭林峰
赖敏
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nanjing University of Information Science and Technology
Original Assignee
Nanjing University of Information Science and Technology
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Nanjing University of Information Science and Technology filed Critical Nanjing University of Information Science and Technology
Priority to CN202111092643.XA priority Critical patent/CN113553997A/en
Publication of CN113553997A publication Critical patent/CN113553997A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06FELECTRIC DIGITAL DATA PROCESSING
    • G06F2218/00Aspects of pattern recognition specially adapted for signal processing
    • G06F2218/02Preprocessing
    • G06F2218/04Denoising
    • G06F2218/06Denoising by applying a scale-space analysis, e.g. using wavelet analysis
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01DMEASURING 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
    • G01D5/00Mechanical 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
    • G01D5/26Mechanical 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
    • G01D5/32Mechanical 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
    • G01D5/34Mechanical 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
    • G01D5/353Mechanical 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
    • G01D5/35338Mechanical 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
    • G01D5/35354Sensor working in reflection
    • G01D5/35358Sensor working in reflection using backscattering to detect the measured quantity
    • G01D5/35364Sensor working in reflection using backscattering to detect the measured quantity using inelastic backscattering to detect the measured quantity, e.g. using Brillouin or Raman backscattering

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Theoretical Computer Science (AREA)
  • Artificial Intelligence (AREA)
  • Computer Vision & Pattern Recognition (AREA)
  • Signal Processing (AREA)
  • General Engineering & Computer Science (AREA)
  • Image Processing (AREA)

Abstract

The invention discloses a signal processing method, a storage medium and a system for jointly improving a wavelet threshold, relates to the field of signal processing of optical fiber sensing in the photoelectric information technology, and particularly relates to a method for improving the signal-to-noise ratio of a signal. In the method, the signal denoising is carried out by combining the accumulation average method with the wavelet threshold improvement method, so that the signal-to-noise ratio of the output signal can be further improved, and the mean square error is further reduced.

Description

Signal processing method, storage medium and system for jointly improving wavelet threshold
Technical Field
The invention belongs to the field of signal processing of optical fiber sensing in the photoelectric information technology, and particularly relates to a signal processing method, a storage medium and a system for jointly improving a wavelet threshold.
Background
The Brillouin Optical Time Domain Reflectometer (BOTDR) is a technology for realizing optical fiber sensing by utilizing the linear relation between Brillouin frequency shift, stress/strain and temperature, can be applied to many large-scale constructions, such as the safety monitoring of bridge dams, tunnel traffic, transmission power grids and the like, and has wide application prospect. However, since the spontaneous brillouin scattering signal is very weak and has interference of various noises, in the long-distance measurement, the useful signal in the sensing optical fiber is easily submerged in the noises, so that the instrument is difficult to detect accurately, and therefore, it is very important to improve the signal-to-noise ratio of the signal acquired by the BOTDR system.
The traditional denoising method is a linear filtering method based on Fourier transform, which is simple and easy to implement, but has contradiction in improving the signal-to-noise ratio and the resolution. The wavelet transformation energy conversion localizes time-frequency characteristics at the same time, is a multi-resolution analysis method, and is widely applied to signal denoising. In 1995, d.l.donoho et al proposed a wavelet threshold denoising algorithm based on wavelet transform, and attracted extensive attention. Wavelet threshold denoising is to decompose and reconstruct a noise-containing signal on the basis of wavelet transformation, after wavelet decomposition, the coefficient of a useful signal is larger than the coefficient of noise, then the decomposed wavelet coefficient is limited by setting a proper threshold, the wavelet coefficient with the absolute value smaller than the threshold is considered to be mainly caused by the noise and is directly set to be zero, the coefficient with the absolute value larger than the threshold is considered to be caused by the signal, the wavelet coefficient is shrunk (soft threshold method) or reserved (hard threshold method) through certain threshold function processing to obtain an estimated wavelet coefficient, and finally, the estimated wavelet coefficient is reconstructed to obtain a denoised signal.
The denoising effect of wavelet threshold denoising depends on the selection of a threshold and the design of a threshold function, and two common threshold denoising methods are a hard threshold denoising method and a soft threshold denoising method. The hard threshold method can retain more characteristics of spikes and the like of a real signal, but the denoising effect can vibrate due to the discontinuity of the hard threshold at the threshold; the soft threshold method overcomes the defect that the hard threshold method is discontinuous at the threshold, and can generate a smooth result after denoising, but constant deviation always exists between the original wavelet coefficient and the wavelet coefficient subjected to threshold quantization processing, high-frequency information of signals is easily lost, and the denoising effect is influenced to a certain extent.
The accumulation averaging method is a method for increasing the signal-to-noise ratio by accumulating measurement data for a plurality of times, and has been widely used in signal noise reduction processing; however, when the accumulated number of times reaches a certain value, the signal-to-noise ratio is increased significantly, and the required storage space and the measurement time are still increased linearly, which is not favorable for hardware implementation and cannot meet the real-time measurement requirement.
Disclosure of Invention
The invention aims to solve the problem that the defects of discontinuity and constant deviation exist in a common threshold denoising method, and provides a signal processing method for jointly improving a wavelet threshold function.
The technical scheme adopted by the invention for solving the problems is as follows: a method of signal processing with joint improvement of wavelet threshold, comprising the steps of:
s1 simulates Brillouin scattering signals acquired by a BOTDR system data acquisition module, and the model is as follows:
Figure 457460DEST_PATH_IMAGE001
where x (t) is a noisy signal, s (t) is an original signal, and n (t) is a noisy signal. The snr can be expressed as:
Figure 218742DEST_PATH_IMAGE002
s2, M noise signals are superposed, for S (t), M times of superposition become Ms (t), and for noise signal n (t), effective value after superposition becomes Ms (t)
Figure 747944DEST_PATH_IMAGE003
Therefore, the snr of the signal after M times of superposition becomes:
Figure 911072DEST_PATH_IMAGE004
from the above equation, the signal-to-noise ratio is improved after M times of accumulation averaging
Figure 31475DEST_PATH_IMAGE005
Doubling;
s3, carrying out H-layer wavelet decomposition on the noise-stained signal obtained by the accumulation average method to obtain a high-frequency wavelet coefficient
Figure 811212DEST_PATH_IMAGE006
Wherein
Figure 878525DEST_PATH_IMAGE007
Representing the kth coefficient in the detail coefficient group of the j layer of the wavelet decomposition;
calculating threshold value by using improved threshold value calculation method, and using a group of wavelet coefficients obtained by comparing the threshold value with improved wavelet threshold value function
Figure 896160DEST_PATH_IMAGE008
Performing threshold quantization to obtain estimated low-frequency wavelet coefficient
Figure 718622DEST_PATH_IMAGE009
High-frequency wavelet coefficient from layer 1 to layer H after threshold quantization
Figure 454497DEST_PATH_IMAGE008
And low frequency wavelet coefficients of the H-th layer
Figure 325501DEST_PATH_IMAGE010
Performing wavelet inverse transformation, and performing signal reconstruction to obtain a reconstructed signal;
further, the brillouin scattering signal acquired by the analog BOTDR system data acquisition module includes:
constructing a sine function, and adding white noise to the sine function by adopting a randn function to obtain a one-dimensional noise-dyeing signal;
further, toPerforming H-layer wavelet decomposition on the one-dimensional noise-contaminated signal obtained by the accumulative average method to obtain a high-frequency wavelet coefficient
Figure 197642DEST_PATH_IMAGE007
The method comprises the following steps:
performing 5-layer wavelet decomposition on the one-dimensional noise-contaminated signal obtained after the accumulation and the averaging by adopting a db4 wavelet basis function to obtain a high-frequency wavelet coefficient
Figure 925427DEST_PATH_IMAGE006
Further, a db4 wavelet basis function is adopted to carry out 5-layer wavelet decomposition on the one-dimensional noise-staining signal obtained after the accumulation and the averaging to obtain a high-frequency wavelet coefficient
Figure 411247DEST_PATH_IMAGE006
The method comprises the following steps:
selecting sym6, sym7, sym8, db1, db3 and db4 wavelet bases to perform wavelet decomposition on wavelets, setting the decomposition layer number to be 3-5 layers, performing matlab simulation comparative analysis, and performing 5-layer wavelet decomposition on the one-dimensional noise-dyed signal by using db4 as the wavelet bases to obtain a high-frequency wavelet coefficient
Figure 617100DEST_PATH_IMAGE011
Further, calculating a threshold value by adopting an improved threshold value calculation method, and comparing the threshold value with an improved wavelet threshold value function to obtain a group of wavelet coefficients
Figure 609327DEST_PATH_IMAGE006
Performing threshold quantization to obtain estimated low-frequency wavelet coefficient
Figure 711275DEST_PATH_IMAGE012
The method comprises the following steps:
calculating the threshold value by adopting an improved threshold value calculation method, wherein the expression of the improved threshold value calculation method is as follows:
Figure 156163DEST_PATH_IMAGE013
Figure 165708DEST_PATH_IMAGE014
wherein
Figure 278020DEST_PATH_IMAGE015
The threshold value of the j layer, j is a decomposition layer, N is the length of a signal, and sigma is the standard deviation of noise, and in practical application, sigma is always unknown, so the estimated value of sigma is used, and median (x) represents the median operation;
combining the wavelet coefficients
Figure 82028DEST_PATH_IMAGE008
Substituted into the improved wavelet threshold function expression
Figure 279791DEST_PATH_IMAGE008
Performing threshold quantization to obtain estimated wavelet coefficient
Figure 827447DEST_PATH_IMAGE012
Wherein the improved wavelet threshold function expression is:
Figure 794266DEST_PATH_IMAGE016
wherein μ is an adjustment factor that improves the threshold function, and μ > 0;
further, the method also comprises the step of introducing an output signal-to-noise ratio (SNR) and a mean square error (RMSE) to verify the denoising effect of the function, wherein the calculation formulas are respectively as follows:
Figure 769175DEST_PATH_IMAGE017
Figure 454235DEST_PATH_IMAGE018
after the signal is denoised, the higher the signal-to-noise ratio of the signal is and the smaller the mean square error is, the closer the denoised signal is to the original signal is, and the better the denoising effect is.
A storage medium having recorded thereon a signal processing method of jointly improving wavelet thresholds as described above.
A computer-implemented system for computing a signal processing method having a jointly improved wavelet threshold as described above.
The technical method has the following beneficial effects that:
the newly proposed wavelet threshold function not only overcomes the defect of discontinuity of the traditional wavelet threshold function, but also effectively solves the problem of constant deviation of the traditional wavelet threshold function, and simultaneously adopts the accumulative average method combined with the improved wavelet threshold method to process the noise-contaminated signal, thereby effectively improving the signal-to-noise ratio, reducing the mean square error and enabling the processed signal to be as close to the original signal as possible.
Drawings
FIG. 1 is a signal processing flow diagram according to the present invention;
FIG. 2 shows the original signal of noise-contaminated signal SNR of-5.88 db and the noise-contaminated signal;
FIG. 3 shows the original signal of noise-contaminated signal SNR of-11.98 db and the noise-contaminated signal;
FIG. 4 is a schematic diagram of an improved threshold function;
FIG. 5 is a diagram of the denoising effect of the signal-to-noise ratio of a noise-contaminated signal of-5.88 db;
FIG. 6 is a diagram of the cumulative joint denoising effect of the noise signal SNR of-5.88 db;
FIG. 7 is a diagram of the noise-removing effect of-11.98 db in the signal-to-noise ratio of a noise-contaminated signal;
FIG. 8 is a diagram of the signal-to-noise ratio of the noise-contaminated signal-11.98 db cumulative joint denoising effect.
Detailed Description
The technical solutions in the embodiments of the present disclosure will be clearly and completely described below with reference to the drawings in the embodiments of the present disclosure, and it is obvious that the described embodiments are only a part of the embodiments of the present disclosure, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments disclosed herein without making any creative effort, shall fall within the protection scope of the present disclosure.
As shown in fig. 1 to 8, a signal processing method for jointly improving wavelet threshold includes the following steps:
step S1: simulating an original signal;
in the present embodiment, the analog original signal expression described in step S1 is:
Figure 805582DEST_PATH_IMAGE019
step S2: adding white noise into the original signal to obtain a one-dimensional noise-dyeing signal;
step S3: denoising the obtained one-dimensional noise-dyeing signal by an accumulation average method;
the accumulation frequency is generally set to be an exponential multiple of 2, but when the accumulation frequency reaches a certain value, the signal-to-noise ratio improvement speed is obviously slowed down, and the required storage space and the measurement time are still linearly increased, in the embodiment, the one-dimensional noise-dyeing signal is subjected to accumulation processing for 512 times;
step S4: performing 5-layer wavelet decomposition on the noise-stained signal obtained in the step S3, selecting db4 as a wavelet base to perform wavelet decomposition on the input signal, and obtaining a high-frequency wavelet coefficient
Figure 626907DEST_PATH_IMAGE008
And a lowest level of approximation coefficients, wherein
Figure 300946DEST_PATH_IMAGE006
Representing the kth coefficient in the detail coefficient group of the j layer of the wavelet decomposition;
in the embodiment, the wavelet bases sym6, sym7, sym8, db1, db3 and db4 are selected for wavelet decomposition, db4 is selected as the wavelet base through matlab simulation comparative analysis, after db4 is selected as the wavelet base, the decomposition layer number of 3-5 layers is also subjected to comparative analysis, and finally 5 layers are selectedDecomposing the layer number, namely selecting db4 wavelet base to carry out 5-layer wavelet decomposition on the one-dimensional noise-stained signal to obtain a high-frequency wavelet coefficient
Figure 942143DEST_PATH_IMAGE007
Step S5: designing an improved wavelet threshold function, calculating a threshold value by adopting an improved threshold value rule, and utilizing the threshold value and the improved wavelet threshold function to perform comparison on the high-frequency wavelet coefficient obtained in the step S4
Figure 831602DEST_PATH_IMAGE011
Performing threshold quantization to obtain estimated low-frequency wavelet coefficient
Figure 773013DEST_PATH_IMAGE009
In this embodiment, step S5 specifically includes the following steps:
step S51: calculating the threshold value by adopting an improved threshold value rule, wherein an improved threshold value expression is as follows:
Figure 89725DEST_PATH_IMAGE013
Figure 483797DEST_PATH_IMAGE014
wherein
Figure 442526DEST_PATH_IMAGE020
The threshold value of the j layer, j is a decomposition layer, N is the length of a signal, and sigma is the standard deviation of noise, and in practical application, sigma is always unknown, so the estimated value of sigma is used, and median (x) represents the median operation;
step S52: using the threshold and the improved wavelet threshold function to perform the wavelet transform on the high frequency wavelet coefficients obtained in step S4
Figure 972864DEST_PATH_IMAGE011
Performing threshold quantization to obtain estimated low-frequency wavelet coefficient
Figure 991636DEST_PATH_IMAGE012
(ii) a Wherein the expression of the modified threshold wavelet threshold function is:
Figure 607425DEST_PATH_IMAGE016
wherein μ is an adjustment factor that improves the threshold function, and μ > 0; the actual value of the adjustment factor can be adjusted in a self-adaptive manner according to the use condition, so that the adjustment factor has stronger self-adaptability;
the continuity of the threshold function is proved and the existing fixed deviation problem is improved by using a mathematical method;
continuity: when in use
Figure 838686DEST_PATH_IMAGE011
Time → th:
Figure 754690DEST_PATH_IMAGE021
it is known that
Figure 678783DEST_PATH_IMAGE022
Therefore, it can be seen that the new function is continuous at + th;
the same principle is that: when in use
Figure 47448DEST_PATH_IMAGE007
On time → th:
Figure 82400DEST_PATH_IMAGE023
it is known that
Figure 787663DEST_PATH_IMAGE024
Therefore, it can be seen that the new function is also continuous at-th;
to sum up: the improved threshold function constructed by the scheme is continuous at +/-th, and the continuity of the improved threshold function shows that the improved threshold function can avoid Gibbs oscillation;
the progressiveness: when in use
Figure 882658DEST_PATH_IMAGE008
→ + ∞time:
Figure 738619DEST_PATH_IMAGE025
Figure 311682DEST_PATH_IMAGE026
the same principle is that: when in use
Figure 936699DEST_PATH_IMAGE008
→ infinity time;
Figure 202595DEST_PATH_IMAGE027
Figure 545852DEST_PATH_IMAGE028
to sum up: the asymptote of the improved threshold function constructed by the scheme is
Figure 188186DEST_PATH_IMAGE029
This indicates that with
Figure 667709DEST_PATH_IMAGE006
The fixed deviation is reduced when the value is increased;
deviation property:
Figure 104506DEST_PATH_IMAGE030
Figure 669480DEST_PATH_IMAGE031
Figure 584346DEST_PATH_IMAGE032
Figure 183955DEST_PATH_IMAGE033
to sum up:
Figure 791654DEST_PATH_IMAGE034
this further verifies that the bias will have less and less impact on the improved threshold function of the scheme;
step S6: high frequency wavelet coefficients of layer 1 to layer 5 after threshold quantization processing
Figure 843923DEST_PATH_IMAGE008
And low frequency wavelet coefficients of layer 5
Figure 562480DEST_PATH_IMAGE035
Performing wavelet inverse transformation, and performing signal reconstruction to obtain a reconstructed signal;
furthermore, the method of the present invention further includes introducing an output signal-to-noise ratio (SNR) and a mean square error (RMSE) to verify the denoising effect, and the calculation formulas are respectively:
Figure 13666DEST_PATH_IMAGE017
Figure 792266DEST_PATH_IMAGE018
under the condition of different signal-to-noise ratios of simulated noise signals, the denoising method and the traditional threshold denoising method are adopted to denoise the signals, and the output signal-to-noise ratio and the mean square error of the denoising method and the traditional threshold are obtained;
table 1: noise reduction effect comparison results of different methods under noise signal to noise ratio of-5.88 db
Denoising method Signal-to-noise ratio (SNR) Mean Square Error (RMSE)
One-dimensional noise signal -5.8754 5.0120
Soft threshold method 5.4018 1.3682
Hard threshold method 4.6773 1.4872
Improved threshold method 5.7091 1.3206
Cumulative averaging method 18.0596 0.3186
Accumulation joint soft threshold method 19.3931 0.2733
Accumulation joint hard threshold method 23.3763 0.1728
Accumulation joint improvement threshold method 24.7935 0.1467
Table 2: noise reduction effect comparison results of different methods under noise signal to noise ratio of-11.98 db
Denoising method Signal-to-noise ratio (SNR) Mean Square Error (RMSE)
One-dimensional noise signal -11.9763 10.1170
Soft threshold method 1.9412 2.0379
Hard threshold method 1.9412 2.0379
Improved threshold method 2.0334 2.0164
Cumulative averaging method 12.4703 0.6064
Accumulation joint soft threshold method 15.7114 0.4175
Accumulation joint hard threshold method 19.0580 0.2840
Accumulation joint improvement threshold method 20.5497 0.2392
In this embodiment, as shown in fig. 5 to 8, denoising effect graphs of different threshold functions are shown, and it can be seen by combining the results of comparing and analyzing denoising effects of different methods in tables 1 and 2 that although the conventional wavelet threshold method can also improve the signal-to-noise ratio of signals and reduce the mean square error, the method for jointly improving the wavelet threshold provided in this embodiment can further improve the signal-to-noise ratio, reduce the mean square error, and maximally and effectively restore signals.
Principle of operation
The signal processing is carried out on the noise-contaminated signal by adopting the accumulation average method and combining the method for improving the wavelet threshold value, so that the signal-to-noise ratio can be effectively improved, the mean square error is reduced, and the processed signal is as close to the original signal as possible.
The above embodiments are only for illustrating the technical idea of the invention, and the protection scope of the invention is not limited thereby, and any modification made on the basis of the technical solution according to the technical idea of the invention falls within the protection scope of the invention. The technology not related to the invention can be realized by the prior art.

Claims (10)

1. A method of signal processing with combined wavelet threshold improvement, the method comprising the steps of: performing multi-layer wavelet decomposition on the noise-stained signals subjected to the accumulation processing to obtain a high-frequency wavelet coefficient; performing threshold quantization processing on the high-frequency wavelet coefficient to obtain a low-frequency wavelet coefficient; and performing wavelet inverse transformation on the high-frequency wavelet coefficient and the low-frequency wavelet coefficient of each layer after threshold quantization processing, and performing signal reconstruction to obtain a reconstructed signal.
2. A method for signal processing with combined wavelet threshold improvement as claimed in claim 1, wherein said noisy signal is obtained by constructing a sine function and adding white noise thereto.
3. A method of wavelet processing combined with wavelet thresholding as claimed in claim 1, wherein said noise-corrupted signal is wavelet decomposed using one of the wavelet bases sym6, sym7, sym8, db1, db3, db 4.
4. A method for signal processing with combined wavelet threshold improvement according to claim 1, wherein the number of decomposition layers of said wavelet decomposition is set to 3-5 layers.
5. A method for processing a signal in combination with an improved wavelet threshold according to claim 1, wherein the method for obtaining the low frequency wavelet system comprises the following steps:
the first step is as follows: calculating a threshold value by adopting an improved threshold value rule;
the second step is that: and performing threshold quantization processing on the high-frequency wavelet coefficient by using the threshold and the improved wavelet threshold function to obtain the low-frequency wavelet coefficient.
6. A method as claimed in claim 1, wherein the number of accumulated processing times of the noise-contaminated signal is an exponential multiple of 2.
7. The method of claim 1, wherein the method comprises introducing an output signal-to-noise ratio and a mean-square error to verify denoising effect.
8. A method for combined wavelet threshold signal processing as claimed in claim 1, wherein said high frequency wavelet coefficients are obtained by 5-layer wavelet decomposition of said noisy signal over a db4 wavelet basis.
9. A storage medium characterized in that it records a signal processing method of jointly improving wavelet thresholds according to claim 1.
10. A computer-implemented system for performing the method of signal processing in conjunction with wavelet thresholding of claim 1.
CN202111092643.XA 2021-09-17 2021-09-17 Signal processing method, storage medium and system for jointly improving wavelet threshold Pending CN113553997A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202111092643.XA CN113553997A (en) 2021-09-17 2021-09-17 Signal processing method, storage medium and system for jointly improving wavelet threshold

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202111092643.XA CN113553997A (en) 2021-09-17 2021-09-17 Signal processing method, storage medium and system for jointly improving wavelet threshold

Publications (1)

Publication Number Publication Date
CN113553997A true CN113553997A (en) 2021-10-26

Family

ID=78134645

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202111092643.XA Pending CN113553997A (en) 2021-09-17 2021-09-17 Signal processing method, storage medium and system for jointly improving wavelet threshold

Country Status (1)

Country Link
CN (1) CN113553997A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114577419A (en) * 2022-04-24 2022-06-03 南京信息工程大学 Method for improving safety monitoring effectiveness of underground diaphragm wall leakage
CN116108336A (en) * 2023-04-13 2023-05-12 吉林省百皓科技有限公司 Chlorine dioxide sensor signal denoising method based on wavelet transformation
CN116399379A (en) * 2023-06-07 2023-07-07 山东省科学院激光研究所 Distributed optical fiber acoustic wave sensing system and measuring method thereof

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108985179A (en) * 2018-06-22 2018-12-11 福建和盛高科技产业有限公司 A kind of electric energy quality signal denoising method based on improvement wavelet threshold function
CN112395992A (en) * 2020-11-18 2021-02-23 云南电网有限责任公司电力科学研究院 Electric power harmonic signal denoising method based on improved wavelet threshold
AU2021101814A4 (en) * 2021-04-08 2021-06-17 Achanta, Sampath Dakshina Murthy MR A novel image denoising method with hybrid dual tree complex wavelet transform
CN113221746A (en) * 2021-05-13 2021-08-06 西南科技大学 Microseismic signal denoising method based on improved wavelet threshold function

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108985179A (en) * 2018-06-22 2018-12-11 福建和盛高科技产业有限公司 A kind of electric energy quality signal denoising method based on improvement wavelet threshold function
CN112395992A (en) * 2020-11-18 2021-02-23 云南电网有限责任公司电力科学研究院 Electric power harmonic signal denoising method based on improved wavelet threshold
AU2021101814A4 (en) * 2021-04-08 2021-06-17 Achanta, Sampath Dakshina Murthy MR A novel image denoising method with hybrid dual tree complex wavelet transform
CN113221746A (en) * 2021-05-13 2021-08-06 西南科技大学 Microseismic signal denoising method based on improved wavelet threshold function

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114577419A (en) * 2022-04-24 2022-06-03 南京信息工程大学 Method for improving safety monitoring effectiveness of underground diaphragm wall leakage
CN116108336A (en) * 2023-04-13 2023-05-12 吉林省百皓科技有限公司 Chlorine dioxide sensor signal denoising method based on wavelet transformation
CN116399379A (en) * 2023-06-07 2023-07-07 山东省科学院激光研究所 Distributed optical fiber acoustic wave sensing system and measuring method thereof
CN116399379B (en) * 2023-06-07 2023-11-03 山东省科学院激光研究所 Distributed optical fiber acoustic wave sensing system and measuring method thereof

Similar Documents

Publication Publication Date Title
CN113553997A (en) Signal processing method, storage medium and system for jointly improving wavelet threshold
WO2021056727A1 (en) Joint noise reduction method based on variational mode decomposition and permutation entropy
CN103630808B (en) A kind of partial discharge signal denoising method based on lifting wavelet transform
CN109557429A (en) Based on the GIS partial discharge fault detection method for improving wavelet threshold denoising
CN112380934B (en) Cable partial discharge signal self-adaptive wavelet denoising method based on wavelet entropy and sparsity
CN112084845B (en) Low-frequency 1/f noise elimination method based on multi-scale wavelet coefficient autocorrelation
CN113723171B (en) Electroencephalogram signal denoising method based on residual error generation countermeasure network
CN113378661A (en) Direct current electric energy signal denoising method based on improved wavelet threshold and related detection
CN109709585B (en) Method for removing colored noise in GPS coordinate time sequence
CN107886078A (en) A kind of Threshold Denoising method based on layered self-adapting threshold function table
CN111507221A (en) Gear signal denoising method based on VMD and maximum overlapping discrete wavelet packet transformation
CN113238190A (en) Ground penetrating radar echo signal denoising method based on EMD combined wavelet threshold
CN106569034A (en) Partial discharge signal de-noising method based on wavelet and high-order PDE
CN114577419B (en) Method for improving safety monitoring effectiveness of underground diaphragm wall leakage
CN105550998A (en) Image enhancement method and image enhancement system based on second-generation wavelet integer transform
CN115165274A (en) Self-adaptive intelligent monitoring device and method for vibration state of engineering mechanical equipment
CN113553960B (en) Wind power climbing uncertainty evaluation method based on wavelet packet variance entropy
CN113297987B (en) Variational modal decomposition signal noise reduction method based on dual-objective function optimization
CN114690003A (en) EEMD-based partial discharge signal noise reduction method
CN110333054A (en) A kind of gradual small fault detection method for white body welding equipment
CN109558857B (en) Chaotic signal noise reduction method
CN110287853B (en) Transient signal denoising method based on wavelet decomposition
CN110248325B (en) Bluetooth indoor positioning system based on signal multiple noise elimination
CN116383605A (en) Vehicle vibration signal denoising method based on wavelet decomposition
CN110703089B (en) Wavelet threshold denoising method for low-frequency oscillation Prony analysis

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
RJ01 Rejection of invention patent application after publication

Application publication date: 20211026

RJ01 Rejection of invention patent application after publication