Data processing method and device for dual Mach-Zehnder vibration sensing system

Abstract

The present application provides a data processing method and device for a dual Mach-Zehnder vibration sensing system. The dual Mach-Zehnder vibration sensing system includes a first photodetector and a second photodetector, and the method includes: obtaining a first upper envelope curve of the interference electrical signal of the first photodetector, wherein the first upper envelope curve includes a plurality of first envelope segments; obtaining a second upper envelope curve of the interference electrical signal of the second photodetector, wherein the second upper envelope curve includes a plurality of second envelope segments; extracting a first envelope segment whose function value exceeds a first threshold value from the plurality of first envelope segments; extracting a second envelope segment whose function value exceeds a second threshold value from the plurality of second envelope segments; performing a cross-correlation operation on the extracted first envelope segment and the corresponding second envelope segment to obtain a first cross-correlation difference; determining the vibration position value according to the first cross-correlation difference and the vibration position solution formula. This scheme realizes the precise positioning of the vibration position.

Description

Technical Field

[0001] The present application relates to the field of dual Mach-Zehnder vibration sensing, and more specifically, to a data processing method, device, computer-readable storage medium, and processor for a dual Mach-Zehnder vibration sensing system. Background Art

[0002] Fiber optic sensing technology is a new sensing technology that has developed rapidly in the 1970s along with the development of optical fiber and fiber optic communication technology. In fiber optic communication systems, optical fiber is used as a medium for long-distance transmission of light wave signals. People soon discovered that one reason why communication quality is easily disturbed is that optical fiber is very sensitive to external environmental factors. For example, changes in environmental conditions such as temperature and pressure will cause changes in light wave parameters, such as changes in intensity, phase, frequency, polarization state, etc. This phenomenon inspired people to propose the concept of fiber optic sensing. If the changes in light wave parameters can be measured, the size of physical quantities such as temperature, pressure, vibration, etc. that cause these light wave parameters to change can be demodulated.

[0003] Due to the many advantages of optical fiber itself: such as wide working frequency band, large dynamic range, suitable for telemetry and remote control, low loss over long distance, easy to bend, small size, light weight, low cost, waterproof, fireproof, explosion-proof, corrosion-resistant, intrinsically insulating, anti-electromagnetic interference, good anti-radiation performance, and little impact on the measured environment, etc., optical fiber sensing technology can be applied to occasions that are extremely difficult or impossible to measure with traditional sensing methods, especially in the fields of aerospace, navigation, petrochemical, electric power industry, nuclear industry, medical equipment, scientific research and other technical fields.

[0004] In addition to the advantages of fiber optic sensors, distributed sensing technology also has unique advantages such as multi-parameter, large capacity, high resolution, long distance, and easy to form a smart network. It integrates sensing and transmission, and can achieve long-distance measurement and monitoring. After only one measurement, the displacement distribution map of the entire fiber area can be obtained without forming a loop; only one system can be used to obtain a large amount of relatively continuous data communication on a sensor fiber loop of several kilometers or even dozens of kilometers. At present, the application and research based on this technology are becoming more and more extensive. It is gradually being used in many different fields, such as third-party damage monitoring of oil and gas pipelines, high-temperature testing of oil wells, etc.

[0005] The dual Mach-Zehnder vibration sensing system in the distributed sensing technology in the prior art has low positioning accuracy and is prone to false alarms. Summary of the invention

[0006] The main purpose of this application is to provide a data processing method, device, computer-readable storage medium and processor for a dual Mach-Zehnder vibration sensing system to solve the problem of low positioning accuracy of the dual Mach-Zehnder vibration sensing system in the distributed sensing technology in the prior art.

[0007] In order to achieve the above-mentioned purpose, according to one aspect of the present application, a data processing method of a dual Mach-Zehnder vibration sensing system is provided, the dual Mach-Zehnder vibration sensing system comprising a first photodetector and a second photodetector, the method comprising: obtaining a first upper envelope curve of an interference electrical signal of the first photodetector, the first upper envelope curve comprising a plurality of first envelope segments; obtaining a second upper envelope curve of an interference electrical signal of the second photodetector, the second upper envelope curve comprising a plurality of second envelope segments; extracting the first envelope segment whose function value exceeds a first threshold value from the plurality of first envelope segments; extracting the second envelope segment whose function value exceeds a second threshold value from the plurality of second envelope segments; performing a cross-correlation operation on the extracted first envelope segment and the corresponding second envelope segment to obtain a first cross-correlation difference; and determining the vibration position value according to the first cross-correlation difference and a vibration position solution formula.

[0008] Furthermore, obtaining a first upper envelope curve of the interference electrical signal of the first photodetector includes: performing Fourier transform and Hilbert transform on the interference electrical signal of the first photodetector to obtain a first upper envelope curve function; and reconstructing the first upper envelope curve function using peak detection and one-dimensional linear interpolation algorithm to obtain the first upper envelope curve.

[0009] Furthermore, the interference electrical signal of the first photodetector is subjected to Fourier transform and Hilbert transform to obtain a first upper envelope curve function, including: performing the Fourier transform on the interference electrical signal of the first photodetector to obtain a Fourier function; setting a frequency response function; determining a Hilbert Fourier function based on the Fourier function and the frequency response function; performing an inverse Fourier transform on the Hilbert Fourier function to obtain a Hilbert function; and performing polar coordinate conversion on the interference electrical signal of the first photodetector and the Hilbert function to obtain the first upper envelope curve function.

[0010] Furthermore, peak detection and one-dimensional linear interpolation algorithm are used to reconstruct the first upper envelope curve function to obtain the first upper envelope curve, including: extracting the peak points in the first upper envelope curve function; performing one-dimensional linear interpolation processing on the peak points to obtain the first upper envelope curve.

[0011] Furthermore, the vibration position value is determined according to the first mutual correlation difference and the vibration position solution formula, including: determining the maximum first mutual correlation difference between the interference electrical signal of the first photodetector and the interference electrical signal of the second photodetector; deleting the first envelope segment and the second envelope segment corresponding to the first mutual correlation difference being greater than the maximum first mutual correlation difference; selecting the envelope segment with the largest peak value from the remaining first envelope segments; performing the mutual correlation operation again on the envelope segment with the largest peak value and the envelope segment at the corresponding position of the second upper envelope curve to obtain a second mutual correlation difference; substituting the second mutual correlation difference into the vibration position solution formula to calculate and obtain the vibration position value.

[0012] Further, determining the maximum first mutual correlation difference between the interference electrical signal of the first photodetector and the interference electrical signal of the second photodetector includes: obtaining the length of the test optical cable, the position of the disturbance signal, the core refractive index, the speed of light in a vacuum, and the sampling period; and determining the maximum first mutual correlation difference based on the length of the test optical cable, the position of the disturbance signal, the core refractive index, the speed of light in a vacuum, and the sampling period.

[0013] Further, after determining the vibration position value according to the first mutual correlation difference and the vibration position solution formula, the method also includes: sorting the multiple vibration position values ​​collected within a predetermined time period to obtain a position array; calculating the absolute value of the difference between the Nth vibration position value and the N+3th vibration position value, where N is an integer greater than or equal to 1; when the absolute value of the difference is less than or equal to a predetermined value, determining that the final vibration position value is the average of the Nth vibration position value, the N+1th vibration position value, the N+2th vibration position value and the N+3th vibration position value.

[0014] According to another aspect of the present application, a data processing device for a dual Mach-Zehnder vibration sensing system is provided, wherein the dual Mach-Zehnder vibration sensing system includes a first photodetector and a second photodetector, and the device includes: a first acquisition unit, used to acquire a first upper envelope curve of an interference electrical signal of the first photodetector, wherein the first upper envelope curve includes a plurality of first envelope segments; a second acquisition unit, used to acquire a second upper envelope curve of an interference electrical signal of the second photodetector, wherein the second upper envelope curve includes a plurality of second envelope segments; a first extraction unit, used to extract the first envelope segment whose function value exceeds a first threshold value from the plurality of the first envelope segments; a second extraction unit, used to extract the second envelope segment whose function value exceeds a second threshold value from the plurality of the second envelope segments; an operation unit, used to perform a cross-correlation operation on the extracted first envelope segment and the corresponding second envelope segment to obtain a first cross-correlation difference; and a first determination unit, used to determine a vibration position value according to the first cross-correlation difference and a vibration position solution formula.

[0015] According to another aspect of the present application, a computer-readable storage medium is provided, wherein the computer-readable storage medium includes a stored program, wherein when the program is run, the device where the computer-readable storage medium is located is controlled to execute any one of the dual Mach-Zehnder vibration sensing system data processing methods.

[0016] According to another aspect of the present application, a processor is provided, wherein the processor is used to run a program, wherein when the program is run, any one of the methods for processing data of a dual Mach-Zehnder vibration sensing system is executed.

[0017] By applying the technical solution of the present application, the first upper envelope curve of the interference electrical signal of the first photodetector is obtained, the second upper envelope curve of the interference electrical signal of the second photodetector is obtained, and then the first envelope segment whose function value exceeds the first threshold value is extracted, and the second envelope segment whose function value exceeds the second threshold value is extracted, and then the first envelope segment and the corresponding second envelope segment are cross-correlated to obtain the first cross-correlation difference, and finally the vibration position value is determined according to the first cross-correlation difference and the vibration position solution formula. The vibration position value is accurately determined, and the use of this solution can reduce the occurrence of false alarms in the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings constituting part of the present application are used to provide a further understanding of the present application. The exemplary embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0019] Figure 1 A schematic diagram of a dual Mach-Zehnder vibration sensing system according to an embodiment of the present application is shown;

[0020] Figure 2 A flow chart of a data processing method for a dual Mach-Zehnder vibration sensing system according to an embodiment of the present application is shown;

[0021] Figure 3 A schematic diagram of a data processing device for a dual Mach-Zehnder vibration sensing system according to an embodiment of the present application is shown. DETAILED DESCRIPTION

[0022] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0023] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present application.

[0024] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present application described here. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0025] It should be understood that when an element (such as a layer, film, region, or substrate) is described as being "on" another element, the element may be directly on the other element, or there may be intermediate elements. Moreover, in the specification and claims, when an element is described as being "connected" to another element, the element may be "directly connected" to the other element, or "connected" to the other element through a third element.

[0026] According to an embodiment of the present application, a data processing method for a dual Mach-Zehnder vibration sensing system is provided.

[0027] Figure 1 is a schematic diagram of a dual Mach-Zehnder vibration sensing system according to an embodiment of the present application. Figure 2is a flow chart of a data processing method for a dual Mach-Zehnder vibration sensing system according to an embodiment of the present application. Figure 1 As shown, the dual Mach-Zehnder vibration sensing system includes a first photodetector (photodetector PD1) and a second photodetector (photodetector PD2), as shown in FIG. Figure 2 As shown, the method comprises the following steps:

[0028] Step S101, obtaining a first upper envelope curve of the interference electrical signal of the first photodetector, wherein the first upper envelope curve includes a plurality of first envelope segments;

[0029] Step S102, obtaining a second upper envelope curve of the interference electrical signal of the second photodetector, wherein the second upper envelope curve includes a plurality of second envelope segments;

[0030] Step S103, extracting the first envelope segment whose function value exceeds the first threshold value from the plurality of the first envelope segments;

[0031] Step S104, extracting the second envelope segment whose function value exceeds the second threshold value from the plurality of the second envelope segments;

[0032] Step S105, performing a cross-correlation operation on the extracted first envelope segment and the corresponding second envelope segment to obtain a first cross-correlation difference;

[0033] Step S106, determining the vibration position value according to the first cross-correlation difference and the vibration position solution formula.

[0034] Specifically, a specific manner of determining the second envelope segment corresponding to the first envelope segment is: determining the corresponding relationship between the first envelope segment and the second envelope segment according to the time of the collected interference electrical signal.

[0035] In the above scheme, by obtaining the first upper envelope curve of the interference electrical signal of the first photodetector, obtaining the second upper envelope curve of the interference electrical signal of the second photodetector, then extracting the first envelope segment whose function value exceeds the first threshold value, extracting the second envelope segment whose function value exceeds the second threshold value, and then performing cross-correlation operation on the first envelope segment and the corresponding second envelope segment to obtain the first cross-correlation difference, and finally determining the vibration position value according to the first cross-correlation difference and the vibration position solution formula. Accurate determination of the vibration position value is achieved, and the use of this scheme can reduce the occurrence of false alarms in the system.

[0036] It should be noted that the steps shown in the flowcharts of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and that, although a logical order is shown in the flowcharts, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0037] In one embodiment of the present application, obtaining a first upper envelope curve of the interference electrical signal of the first photodetector includes: performing Fourier transform and Hilbert transform on the interference electrical signal of the first photodetector to obtain a first upper envelope curve function; and reconstructing the first upper envelope curve function using peak detection and a one-dimensional linear interpolation algorithm to obtain the first upper envelope curve, so as to obtain an accurate first upper envelope curve.

[0038] In one embodiment of the present application, Fourier transform and Hilbert transform are performed on the interference electric signal of the first photodetector to obtain the first upper envelope curve function, including: performing the above-mentioned Fourier transform on the interference electric signal of the first photodetector to obtain the Fourier function; setting the frequency response function; determining the Hilbert Fourier function according to the above-mentioned Fourier function and the above-mentioned frequency response function; performing inverse Fourier transform on the above-mentioned Hilbert Fourier function to obtain the Hilbert function; performing polar coordinate conversion on the interference electric signal of the first photodetector and the above-mentioned Hilbert function to obtain the above-mentioned first upper envelope curve function. In this way, an accurate first upper envelope curve function is obtained.

[0039] In one embodiment of the present application, peak detection and one-dimensional linear interpolation algorithm are used to reconstruct the above-mentioned first upper envelope curve function to obtain the above-mentioned first upper envelope curve, including: extracting the peak points in the above-mentioned first upper envelope curve function; performing one-dimensional linear interpolation processing on the above-mentioned peak points to obtain the above-mentioned first upper envelope curve.

[0040] In one embodiment of the present application, the vibration position value is determined according to the first mutual correlation difference and the vibration position solution formula, including: determining the maximum first mutual correlation difference between the interference electrical signal of the first photodetector and the interference electrical signal of the second photodetector; deleting the first envelope segment and the second envelope segment corresponding to the first mutual correlation difference greater than the maximum first mutual correlation difference; selecting the envelope segment with the largest peak value from the remaining first envelope segments; performing the above-mentioned mutual correlation operation again on the envelope segment with the largest peak value and the envelope segment at the corresponding position of the second upper envelope curve to obtain the second mutual correlation difference; substituting the above-mentioned second mutual correlation difference into the above-mentioned vibration position solution formula to calculate and obtain the above-mentioned vibration position value. To accurately determine the vibration position value.

[0041] In one embodiment of the present application, determining the maximum first mutual correlation difference between the interference electrical signal of the above-mentioned first photodetector and the interference electrical signal of the above-mentioned second photodetector includes: obtaining the length of the test optical cable, the position of the disturbance signal, the core refractive index, the speed of light in a vacuum and the sampling period; determining the above-mentioned maximum first mutual correlation difference according to the length of the above-mentioned test optical cable, the position of the above-mentioned disturbance signal, the above-mentioned core refractive index, the above-mentioned speed of light in a vacuum and the above-mentioned sampling period.

[0042] In one embodiment of the present application, after determining the vibration position value according to the first mutual correlation difference and the vibration position solution formula, the method further includes: sorting the multiple vibration position values ​​collected within a predetermined time period to obtain a position array; calculating the absolute value of the difference between the Nth vibration position value and the N+3th vibration position value, where N is an integer greater than or equal to 1; when the absolute value of the difference is less than or equal to a predetermined value, determining that the final vibration position value is the average of the Nth vibration position value, the N+1th vibration position value, the N+2th vibration position value and the N+3th vibration position value.

[0043] The embodiment of the present application also provides a dual Mach-Zehnder vibration sensor system data processing device. It should be noted that the dual Mach-Zehnder vibration sensor system data processing device of the embodiment of the present application can be used to execute the dual Mach-Zehnder vibration sensor system data processing method provided in the embodiment of the present application. The dual Mach-Zehnder vibration sensor system data processing device provided in the embodiment of the present application is introduced below.

[0044] Figure 3 is a schematic diagram of a data processing device for a dual Mach-Zehnder vibration sensing system according to an embodiment of the present application. The dual Mach-Zehnder vibration sensing system comprises a first photodetector and a second photodetector, such as Figure 3 As shown, the device comprises:

[0045] A first acquisition unit 10 is used to acquire a first upper envelope curve of the interference electrical signal of the first photodetector, wherein the first upper envelope curve includes a plurality of first envelope segments;

[0046] A second acquisition unit 20, configured to acquire a second upper envelope curve of the interference electrical signal of the second photodetector, wherein the second upper envelope curve includes a plurality of second envelope segments;

[0047] A first extraction unit 30, configured to extract the first envelope segment whose function value exceeds a first threshold value from the plurality of first envelope segments;

[0048] A second extraction unit 40, configured to extract the second envelope segment whose function value exceeds a second threshold value from the plurality of second envelope segments;

[0049] A calculation unit 50 is used to perform a cross-correlation operation on the extracted first envelope segment and the corresponding second envelope segment to obtain a first cross-correlation difference;

[0050] The first determining unit 60 is used to determine the vibration position value according to the first cross-correlation difference and the vibration position solution formula.

[0051] In the above scheme, the first acquisition unit acquires the first upper envelope curve of the interference electrical signal of the first photodetector, the second acquisition unit acquires the second upper envelope curve of the interference electrical signal of the second photodetector, the first extraction unit extracts the first envelope segment whose function value exceeds the first threshold value, the second extraction unit extracts the second envelope segment whose function value exceeds the second threshold value, the operation unit performs cross-correlation operation on the first envelope segment and the corresponding second envelope segment to obtain the first cross-correlation difference, and the first determination unit determines the vibration position value according to the first cross-correlation difference and the vibration position solution formula. The accurate determination of the vibration position value is achieved, and the use of this scheme can reduce the occurrence of false alarms in the system.

[0052] In one embodiment of the present application, the first acquisition unit includes a transformation module and a reconstruction module, wherein the transformation module is used to perform Fourier transform and Hilbert transform on the interference electrical signal of the first photodetector to obtain a first upper envelope curve function; and the reconstruction module is used to reconstruct the first upper envelope curve function using peak detection and one-dimensional linear interpolation algorithm to obtain the first upper envelope curve, so as to obtain an accurate first upper envelope curve.

[0053] In one embodiment of the present application, the transformation module includes a first transformation submodule, a setting submodule, a first determination submodule, a second transformation submodule and a conversion submodule, wherein the first transformation submodule is used to perform the above-mentioned Fourier transformation on the interference electrical signal of the above-mentioned first photodetector to obtain the Fourier function; the setting submodule is used to set the frequency response function; the first determination submodule is used to determine the Hilbert Fourier function according to the above-mentioned Fourier function and the above-mentioned frequency response function; the second transformation submodule is used to perform an inverse Fourier transformation on the above-mentioned Hilbert Fourier function to obtain the Hilbert function; the conversion submodule is used to perform polar coordinate transformation on the interference electrical signal of the above-mentioned first photodetector and the above-mentioned Hilbert function to obtain the above-mentioned first upper envelope curve function. In order to obtain an accurate first upper envelope curve function.

[0054] In one embodiment of the present application, the reconstruction module is further used to extract the peak points in the above-mentioned first upper envelope curve function; and perform one-dimensional linear interpolation processing on the above-mentioned peak points to obtain the above-mentioned first upper envelope curve.

[0055] In one embodiment of the present application, the first determination unit includes a second determination submodule, a deletion submodule, a selection submodule, an operation submodule and a calculation submodule, wherein the second determination submodule is used to determine the maximum first mutual correlation difference between the interference electrical signal of the first photodetector and the interference electrical signal of the second photodetector; the deletion submodule is used to delete the first envelope segment and the second envelope segment corresponding to the first mutual correlation difference greater than the maximum first mutual correlation difference; the selection submodule is used to select the envelope segment with the largest peak value from the remaining first envelope segments; the operation submodule is used to perform the above-mentioned cross-correlation operation again on the envelope segment with the largest peak value and the envelope segment at the corresponding position of the second upper envelope curve to obtain the second cross-correlation difference; the calculation submodule is used to substitute the above-mentioned second cross-correlation difference into the above-mentioned vibration position solution formula to obtain the above-mentioned vibration position value. In order to accurately determine the vibration position value.

[0056] In one embodiment of the present application, the second determination submodule is also used to obtain the length of the test optical cable, the position of the disturbance signal, the core refractive index, the speed of light in a vacuum and the sampling period; based on the length of the test optical cable, the position of the disturbance signal, the core refractive index, the speed of light in a vacuum and the sampling period, the maximum first cross-correlation difference is determined.

[0057] In one embodiment of the present application, the above-mentioned device also includes a sorting unit, a calculation unit and a second determination unit. The sorting unit is used to determine the vibration position value according to the above-mentioned first mutual correlation difference and the vibration position solution formula, and then sort the multiple vibration position values ​​collected within a predetermined time period to obtain a position array; the calculation unit is used to calculate the absolute value of the difference between the Nth vibration position value and the N+3th vibration position value, where N is an integer greater than or equal to 1; the second determination unit is used to determine that the final vibration position value is the average of the Nth vibration position value, the N+1th vibration position value, the N+2th vibration position value and the N+3th vibration position value when the absolute value of the difference is less than or equal to a predetermined value.

[0058] The dual Mach-Zehnder vibration sensing system data processing device includes a processor and a memory. The first acquisition unit, the second acquisition unit, the first extraction unit, the second extraction unit, the calculation unit and the first determination unit are all stored in the memory as program units, and the processor executes the program units stored in the memory to realize corresponding functions.

[0059] The processor includes a kernel, which calls the corresponding program unit from the memory. One or more kernels can be set, and the vibration position value can be accurately determined by adjusting the kernel parameters.

[0060] The memory may include non-permanent memory in a computer-readable medium, random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM, and the memory includes at least one memory chip.

[0061] An embodiment of the present invention provides a computer-readable storage medium, which includes a stored program, wherein when the program is running, the device where the computer-readable storage medium is located is controlled to execute the dual Mach-Zehnder vibration sensing system data processing method.

[0062] An embodiment of the present invention provides a processor, which is used to run a program, wherein the dual Mach-Zehnder vibration sensor system data processing method is executed when the program is running.

[0063] An embodiment of the present invention provides a device, the device including a processor, a memory, and a program stored in the memory and executable on the processor, and when the processor executes the program, at least the following steps are implemented:

[0064] Step S101, obtaining a first upper envelope curve of the interference electrical signal of the first photodetector, wherein the first upper envelope curve includes a plurality of first envelope segments;

[0065] Step S102, obtaining a second upper envelope curve of the interference electrical signal of the second photodetector, wherein the second upper envelope curve includes a plurality of second envelope segments;

[0066] Step S103, extracting the first envelope segment whose function value exceeds the first threshold value from the plurality of the first envelope segments;

[0067] Step S104, extracting the second envelope segment whose function value exceeds the second threshold value from the plurality of the second envelope segments;

[0068] Step S105, performing a cross-correlation operation on the extracted first envelope segment and the corresponding second envelope segment to obtain a first cross-correlation difference;

[0069] Step S106, determining the vibration position value according to the first cross-correlation difference and the vibration position solution formula.

[0070] The devices in this article can be servers, PCs, PADs, mobile phones, etc.

[0071] The present application also provides a computer program product, which, when executed on a data processing device, is suitable for executing a program for initializing at least the following method steps:

[0072] Step S101, obtaining a first upper envelope curve of the interference electrical signal of the first photodetector, wherein the first upper envelope curve includes a plurality of first envelope segments;

[0073] Step S102, obtaining a second upper envelope curve of the interference electrical signal of the second photodetector, wherein the second upper envelope curve includes a plurality of second envelope segments;

[0074] Step S103, extracting the first envelope segment whose function value exceeds the first threshold value from the plurality of the first envelope segments;

[0075] Step S104, extracting the second envelope segment whose function value exceeds the second threshold value from the plurality of the second envelope segments;

[0076] Step S105, performing a cross-correlation operation on the extracted first envelope segment and the corresponding second envelope segment to obtain a first cross-correlation difference;

[0077] Step S106, determining the vibration position value according to the first cross-correlation difference and the vibration position solution formula.

[0078] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0079] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0080] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0081] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0082] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0083] The memory may include non-permanent memory in a computer-readable medium, random access memory (RAM) and / or non-volatile memory in the form of read-only memory (ROM) or flash RAM. The memory is an example of a computer-readable medium.

[0084] Computer readable media include permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. Information can be computer readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disk read-only memory (CD-ROM), digital versatile disk (DVD) or other optical storage, magnetic cassettes, magnetic tape magnetic disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer readable media does not include temporary computer readable media (transitory media), such as modulated data signals and carrier waves.

[0085] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, commodity or device including the elements.

[0086] Example

[0087] This embodiment relates to a specific dual Mach-Zehnder vibration sensor system data processing method, including:

[0088] First, obtain the upper envelope curve of the photodetector PD1. When vibration occurs near the sensing fiber, the vibration signal will trigger the acquisition card to collect vibration information. The electrical signal g(t) of the photodetector PD1 can be obtained through the acquisition card and computer processing. Perform Fourier transform on the function g(t) to obtain G(f) = F{g(t)}, and set the frequency response function as shown in formula (1).

[0089]

[0090] According to the properties of Fourier transform, the Fourier transform of the Hilbert transform of g(t) is shown in formula (2).

[0091] H(f)=-jsgn(f)G(f) (2)

[0092] Perform an inverse Fourier transform on H(f) to obtain the Hilbert transform h(t) of g(t). Finally, perform a real and imaginary part to polar coordinate conversion to obtain the upper envelope curve function, as shown in formula (3).

[0093]

[0094] There are many envelope segments in the envelope curve of the PD1 electrical signal. If the position of each envelope is determined and cross-correlated with the corresponding envelope in the PD2 electrical signal, the amount of calculation is large. The envelope segments with larger amplitudes in the envelope curve of PD1 can be extracted and their positions determined. In the process of extracting some envelope segments, it is necessary to find the peak of the envelope curve and reconstruct the envelope curve by interpolation of the peak points. In the process of finding the envelope curve, the least squares quadratic fitting function is used, as shown in formula (4).

[0095] I1(t)=a0+a1t+a2t 2 (4)

[0096] The solution matrix is ​​shown in formula (5).

[0097]

[0098] The peak position and amplitude in the envelope are determined by the method of least squares quadratic fitting and second-order derivative. The peak position I is when the second-order derivative of the fitted quadratic function changes from negative to positive. 1j, when the second-order derivative changes from positive to negative, it is the trough position. In order to reduce the number of peaks and facilitate subsequent signal processing operations, the width of the peak detection can be appropriately increased to 800, and the width is used to specify the number of continuous data points used in the least squares fitting.

[0099] Perform one-dimensional linear interpolation processing on the obtained peak points and calculate the formula, as shown in formula (6).

[0100]

[0101] Through one-dimensional linear interpolation, the upper envelope curve function I1(x) can be obtained.

[0102] Next, perform envelope division. Let the maximum value in the upper envelope curve be I 1max , set the envelope curve threshold value to Extract the envelope segment (x a1 ,x b1 )、(x a2 ,x b2 ),...,(x an ,x bn ), and at the same time, the envelope length L of each segment is obtained, and the calculation formula is shown in formula (7).

[0103] L abi =|x ai -x bi | (7)

[0104] The length of each envelope segment is L ab1 , L ab2 、···、L abn .

[0105] Each envelope segment in the PD1 electrical signal is used to perform cross-correlation operations with the corresponding envelope segment in the PD2 electrical signal. The cross-correlation function is shown in formula (8).

[0106]

[0107] Assume that the positions of the maximum values ​​in the cross-correlation results are loc i , calculate the cross-correlation difference m of each envelope segment respectively i , as shown in formula (9).

[0108] m i =|loc i -L i | (9)

[0109] Since the length of the optical cable is limited, the cross-correlation difference m between the electrical signals of PD1 and PD2 is iFinite, let the maximum value be M, and the calculation method of M value is shown in formula (10).

[0110]

[0111] Where L is the test distance, i.e. the length of the test optical cable, X is the position of the disturbance signal, n is the core refractive index, c is the speed of light in vacuum, and T = 0.1ns is the sampling period. Based on the known M value, delete m i >The corresponding envelope segment of M (x ai ,x bi ), select the envelope segment with the largest peak value in the envelope from the remaining envelope segments and perform cross-correlation operation with the envelope segment at the corresponding position in the PD2 electrical signal to obtain the cross-correlation difference m, and then substitute m into the vibration position solution formula to obtain the vibration position value. The vibration position solution is shown in formula (11).

[0112]

[0113] Finally, threshold processing is performed on the vibration data within the current minute, that is, the vibration position values ​​collected within the current minute are sorted in order of size to obtain the position arrays X1, X2, .., X j , ···, and perform difference calculation on the array, as shown in formula (12).

[0114] H k =|X j- X j+3 | (12)

[0115] When H k When ≤100, It is output as the final positioning position and the four position values ​​used to obtain the result are deleted from the position array. The calculation method is shown in formula (13).

[0116]

[0117] Calculate the position array in sequence to find the final positioning position.

[0118] From the above description, it can be seen that the above embodiments of the present application achieve the following technical effects:

[0119] 1) The data processing method of the dual Mach-Zehnder vibration sensing system of the present application obtains the first upper envelope curve of the interference electrical signal of the first photodetector, obtains the second upper envelope curve of the interference electrical signal of the second photodetector, then extracts the first envelope segment whose function value exceeds the first threshold value, extracts the second envelope segment whose function value exceeds the second threshold value, and then performs a cross-correlation operation on the first envelope segment and the corresponding second envelope segment to obtain the first cross-correlation difference, and finally determines the vibration position value according to the first cross-correlation difference and the vibration position solution formula. The accurate determination of the vibration position value is achieved, and the use of this solution can reduce the occurrence of false alarms in the system.

[0120] 2) The data processing device of the dual Mach-Zehnder vibration sensing system of the present application, the first acquisition unit acquires the first upper envelope curve of the interference electrical signal of the first photodetector, the second acquisition unit acquires the second upper envelope curve of the interference electrical signal of the second photodetector, the first extraction unit extracts the first envelope segment whose function value exceeds the first threshold value, the second extraction unit extracts the second envelope segment whose function value exceeds the second threshold value, the operation unit performs cross-correlation operation on the first envelope segment and the corresponding second envelope segment to obtain the first cross-correlation difference, and the first determination unit determines the vibration position value according to the first cross-correlation difference and the vibration position solution formula. The accurate determination of the vibration position value is achieved, and the use of this solution can reduce the occurrence of false alarms in the system.

[0121] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A data processing method for a dual Mach-Zehnder vibration sensing system, characterized in that: The dual Mach-Zehnder vibration sensing system includes a first photodetector and a second photodetector, and the method includes: Acquire a first upper envelope curve of the interference electrical signal of the first photodetector, wherein the first upper envelope curve includes a plurality of first envelope segments; Acquire a second upper envelope curve of the interference electrical signal of the second photodetector, wherein the second upper envelope curve includes a plurality of second envelope segments; Extracting the first envelope segment whose function value exceeds a first threshold value from the plurality of the first envelope segments; Extracting, from the plurality of the second envelope segments, the second envelope segment whose function value exceeds a second threshold value; performing a cross-correlation operation on the extracted first envelope segment and the corresponding second envelope segment to obtain a first cross-correlation difference; Determine the vibration position value according to the first cross-correlation difference and the vibration position solution formula, Wherein, obtaining a first upper envelope curve of the interference electrical signal of the first photodetector includes: performing Fourier transform and Hilbert transform on the interference electrical signal of the first photodetector to obtain a first upper envelope curve function; using peak detection and one-dimensional linear interpolation algorithm to reconstruct the first upper envelope curve function to obtain the first upper envelope curve, Among them, obtaining the second upper envelope curve of the interference electrical signal of the second photodetector includes: performing Fourier transform and Hilbert transform on the interference electrical signal of the second photodetector to obtain a second upper envelope curve function; using peak detection and one-dimensional linear interpolation algorithm to reconstruct the second upper envelope curve function to obtain the second upper envelope curve.

2. The processing method according to claim 1, characterized in that: Performing Fourier transform and Hilbert transform on the interference electrical signal of the first photodetector to obtain a first upper envelope curve function, including: Performing the Fourier transform on the interference electrical signal of the first photodetector to obtain a Fourier function; Set the frequency response function; Determining a Hilbert Fourier function based on the Fourier function and the frequency response function; Performing an inverse Fourier transform on the Hilbert Fourier function to obtain a Hilbert function; Polar coordinate conversion is performed on the interference electrical signal of the first photodetector and the Hilbert function to obtain the first upper envelope curve function.

3. The processing method according to claim 1, characterized in that: The first upper envelope curve function is reconstructed by using a peak detection and a one-dimensional linear interpolation algorithm to obtain the first upper envelope curve, including: Extracting the peak point in the first upper envelope curve function; One-dimensional linear interpolation processing is performed on the wave peak points to obtain the first upper envelope curve.

4. The processing method according to claim 1, characterized in that: Determining the vibration position value according to the first cross-correlation difference and the vibration position solution formula includes: Determining a maximum first cross-correlation difference between the interference electrical signal of the first photodetector and the interference electrical signal of the second photodetector; deleting the first envelope segment and the second envelope segment corresponding to the first mutual correlation difference being greater than the maximum first mutual correlation difference; Selecting the envelope segment with the largest peak value from the remaining first envelope segments; Performing the cross-correlation operation again on the envelope segment with the largest peak value and the envelope segment at the corresponding position of the second upper envelope curve to obtain a second cross-correlation difference; Substitute the second cross-correlation difference into the vibration position solution formula to obtain the vibration position value.

5. The processing method according to claim 4, characterized in that: Determining a maximum first cross-correlation difference between the interference electrical signal of the first photodetector and the interference electrical signal of the second photodetector comprises: Obtain the length of the test optical cable, the position of the disturbance signal, the fiber core refractive index, the speed of light in vacuum and the sampling period; The maximum first cross-correlation difference is determined according to the length of the test optical cable, the position of the disturbance signal, the fiber core refractive index, the speed of light in vacuum and the sampling period.

6. The processing method according to claim 1, characterized in that: After determining the vibration position value according to the first cross-correlation difference and the vibration position solution formula, the method further includes: Sorting the plurality of vibration position values ​​collected within a predetermined time period to obtain a position array; Calculate the absolute value of the difference between the Nth vibration position value and the N+3th vibration position value, where N is an integer greater than or equal to 1; When the absolute value of the difference is less than or equal to a predetermined value, the final vibration position value is determined to be the average of the Nth vibration position value, the N+1th vibration position value, the N+2th vibration position value and the N+3th vibration position value.

7. A data processing device for a dual Mach-Zehnder vibration sensing system, characterized in that: The dual Mach-Zehnder vibration sensing system comprises a first photodetector and a second photodetector, and the device comprises: A first acquisition unit, configured to acquire a first upper envelope curve of the interference electrical signal of the first photodetector, wherein the first upper envelope curve includes a plurality of first envelope segments; a second acquisition unit, configured to acquire a second upper envelope curve of the interference electrical signal of the second photodetector, wherein the second upper envelope curve includes a plurality of second envelope segments; A first extraction unit, configured to extract, from the plurality of first envelope segments, the first envelope segment whose function value exceeds a first threshold value; A second extraction unit, configured to extract, from the plurality of second envelope segments, the second envelope segment whose function value exceeds a second threshold value; an operation unit, configured to perform a cross-correlation operation on the extracted first envelope segment and the corresponding second envelope segment to obtain a first cross-correlation difference; A first determining unit, configured to determine a vibration position value according to the first cross-correlation difference and a vibration position solution formula; The first acquisition unit includes a transformation module and a reconstruction module, wherein the transformation module is used to perform Fourier transformation and Hilbert transformation on the interference electrical signal of the first photodetector to obtain a first upper envelope curve function; the reconstruction module is used to reconstruct the first upper envelope curve function by using peak detection and one-dimensional linear interpolation algorithm to obtain the first upper envelope curve; The second acquisition unit is specifically implemented by performing Fourier transform and Hilbert transform on the interference electrical signal of the second photodetector to obtain a second upper envelope curve function, and reconstructing the second upper envelope curve function using peak detection and one-dimensional linear interpolation algorithm to obtain the second upper envelope curve.

8. A computer-readable storage medium, characterized in that: The computer-readable storage medium includes a stored program, wherein when the program is executed, the device where the computer-readable storage medium is located is controlled to execute the data processing method of the dual Mach-Zehnder vibration sensing system according to any one of claims 1 to 6.

9. A processor, characterized in that: The processor is used to run a program, wherein the program, when running, executes the dual Mach-Zehnder vibration sensing system data processing method according to any one of claims 1 to 6.

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