Data processing method of multi-parameter interference type optical fiber sensing system and related equipment

Abstract

According to the data processing method and related equipment of the multi-parameter interference type optical fiber sensing system provided by the embodiment of the invention, the multi-parameter interference type optical fiber sensing system comprises a plurality of interference type optical fiber sensors, a synthetic wavelength division multiplexer and a spectrograph, and the method comprises the following steps: obtaining interference spectrums of the interference type optical fiber sensors, determining the working wave band of each interference type optical fiber sensor based on the interference spectrum; a receiving wavelength division multiplexer is used for dividing a target light source, in each interference type optical fiber sensor, a corresponding working wave band is used for responding to the divided target light source to obtain physical parameter signals, and the physical parameter signals are different from one another; inputting all the physical parameter signals into a synthesis wavelength division multiplexer for synthesis processing to obtain a composite optical signal; and the composite optical signal is input into a spectrograph for analysis and processing to obtain a multi-parameter analysis result of the target light source, so that the channel multiplexing capability and the overall working efficiency of the sensing system are improved, and efficient utilization of spectrum resources is realized.

Description

Technical Field

[0001] The present application relates to the field of optical fiber sensing technology, and in particular to a data processing method and related equipment for a multi-parameter interferometric optical fiber sensing system. Background Art

[0002] In the field of fiber optic sensing, interferometric fiber optic sensors are widely used due to their high sensitivity and anti-electromagnetic interference advantages. In related technologies, when using interferometric fiber optic sensors (such as Fabry-Perot cavities, Mach-Zehnder interferometers and other structures) to detect physical quantities (such as pressure, temperature, etc.), a broadband light source is usually used to provide input light for a single interferometric sensor, and then a spectrometer is used to capture and analyze the interference spectrum output by the sensor, and the change of the external physical quantity is obtained based on the change of the interference optical path difference of the interference spectrum. However, when demodulating using a broadband light source and a spectrometer, the interference spectrum fringes of a single interferometric fiber optic sensor are usually distributed over a very wide wavelength range, and even occupy the entire spectrum of the broadband light source, resulting in only a single interferometric fiber optic sensor being used in a sensing system at the same time to analyze the change of a single physical quantity using the interference spectrum obtained by capture and analysis, which greatly limits the working efficiency of the interferometric fiber optic sensing system and causes a low utilization rate of spectral resources. Summary of the Invention

[0003] The embodiments of the present application provide a data processing method and related equipment for a multi-parameter interferometric fiber optic sensing system, which can improve the spectral resource utilization rate of the interferometric fiber optic sensing system.

[0004] To achieve the above objectives, a first aspect of an embodiment of the present application provides a data processing method for a multi-parameter interferometric fiber optic sensing system, wherein the multi-parameter interferometric fiber optic sensing system includes a plurality of interferometric fiber optic sensors, a synthesizer wavelength division multiplexer, and a spectrometer. The method includes:

[0005] Obtaining an interference spectrum of the interferometric fiber optic sensor, and determining an operating band of each interferometric fiber optic sensor based on the interference spectrum, wherein the operating bands of every two interferometric fiber optic sensors do not overlap;

[0006] The target light source is divided by the receiving wavelength division multiplexer, and in each of the interferometric optical fiber sensors, the corresponding working band is used to respond to the divided target light source to obtain physical parameter signals, wherein the physical parameter signals are different from each other;

[0007] Inputting all the physical parameter signals into the synthesizing wavelength division multiplexer for synthesis processing to obtain a composite optical signal;

[0008] The composite light signal is input into a spectrometer for analysis and processing to obtain a multi-parameter analysis result of the target light source.

[0009] In some embodiments, acquiring the interference spectrum of the interferometric fiber optic sensor and determining the operating band of each interferometric fiber optic sensor based on the interference spectrum includes:

[0010] Performing spectral measurement on the interferometric optical fiber sensor in an atmospheric environment to obtain an interference spectrum, wherein the interference spectrum includes beam phases of multiple light beams;

[0011] Determining a plurality of non-overlapping interference sub-bands in the interference spectrum based on a phase difference between each two of the light beams;

[0012] A different interference sub-band is selected for each of the interferometric optical fiber sensors as the working band of the interferometric optical fiber sensor.

[0013] In some embodiments, determining a plurality of non-overlapping interference sub-bands in the interference spectrum based on the phase difference between each two of the light beams comprises:

[0014] Taking each two phases of the light beams as test phases one by one, and when the phase difference between the test phases is a preset angle, taking the wavelength values corresponding to the two phases of the light beams corresponding to the test phases as a trough wavelength pair;

[0015] Candidate wavelength pairs are obtained based on all the trough wavelength pairs, and the trough wavelength pairs that do not overlap with each other are selected from all the candidate wavelength pairs to obtain the interferometer band.

[0016] In some embodiments, the multi-parameter interferometric fiber optic sensing system includes a receiving wavelength division multiplexer, and the receiving wavelength division multiplexer is used to divide the target light source, and in each of the interferometric fiber optic sensors, the corresponding working band is used to respond to the divided target light source to obtain a physical parameter signal, including:

[0017] For each of the interferometric fiber optic sensors, using the corresponding working band, select a wavelength division multiplexing sub-channel having a central wavelength matching the working band from the multiple wavelength division multiplexing sub-channels of the receiving wavelength division multiplexer as a matching sub-channel of the interferometric fiber optic sensor, and connect the interferometric fiber optic sensor to the corresponding matching sub-channel;

[0018] After each matching sub-channel in the receiving wavelength division multiplexer receives the target light source, the target light source is divided using the corresponding working band to obtain a changing sub-light beam corresponding to each matching sub-channel, and the changing sub-light beam is transmitted to the corresponding interferometric optical fiber sensor;

[0019] In each of the interferometric optical fiber sensors, the corresponding operating wavelength band is used to respond to the changing sub-beam to obtain the physical parameter signal.

[0020] In some embodiments, the operating band includes a peak wavelength and a band bandwidth, and for each of the interferometric optical fiber sensors, using the corresponding operating band, selecting a wavelength division multiplexing sub-channel having a center wavelength matching the operating band from multiple wavelength division multiplexing sub-channels of the receiving wavelength division multiplexer as a matching sub-channel of the interferometric optical fiber sensor, including:

[0021] Using each of the interferometric optical fiber sensors as a matching sensor one by one;

[0022] A wavelength division multiplexing sub-channel whose difference between a center wavelength and the peak wavelength is less than a preset tolerance value and whose channel bandwidth is greater than the band bandwidth is selected from the plurality of wavelength division multiplexing sub-channels as the matching sub-channel corresponding to the matching sensor.

[0023] In some embodiments, inputting the composite light signal into a spectrometer for analysis and processing to obtain a multi-parameter analysis result of the target light source includes:

[0024] In the spectrometer, each working band in the composite optical signal is analyzed respectively to obtain a variation of interference fringes;

[0025] The optical path difference variation of the physical parameter corresponding to the working band is obtained based on the product of the interference fringe variation and the optical fiber refractive index of the matching sub-channel corresponding to the working band, and then divided by the peak wavelength of the working band;

[0026] Obtaining parameter analysis results corresponding to physical parameters corresponding to the working band based on the optical path difference variation;

[0027] Based on the parameter analysis results corresponding to all the physical parameters, the multi-parameter analysis result of the target light source is obtained.

[0028] In some embodiments, inputting all the physical parameter signals into the synthesizing wavelength division multiplexer for synthesis processing to obtain a composite optical signal includes:

[0029] In the synthesized wavelength division multiplexer, index processing is performed based on the product of the fiber attenuation coefficient and the fiber transmission length of each physical parameter signal to obtain the fiber index parameter corresponding to each physical parameter signal;

[0030] The product of the optical fiber index parameter and the light intensity of each of the physical parameter signals is accumulated to obtain the composite optical signal.

[0031] To achieve the above objectives, a second aspect of an embodiment of the present application provides a multi-parameter interferometric optical fiber sensing system, comprising:

[0032] Multiple interferometric fiber optic sensors, a synthesizing wavelength division multiplexer, a receiving wavelength division multiplexer, a spectrometer, and a control processor;

[0033] The receiving wavelength division multiplexer is used to receive the target light source and obtain a plurality of changing sub-light beams after dividing;

[0034] The interferometric optical fiber sensor is used to receive the corresponding changing sub-beam and respond using the corresponding working band to obtain a physical parameter signal;

[0035] The synthesizing wavelength division multiplexer is used to synthesize the multiple physical parameter signals to obtain a composite optical signal;

[0036] The spectrometer is used to analyze and process the composite light signal to obtain a multi-parameter analysis result of the target light source;

[0037] The control processor is used to execute the data processing method of the multi-parameter interferometric optical fiber sensing system according to claim 1.

[0038] To achieve the above-mentioned purpose, the third aspect of an embodiment of the present application proposes an electronic device, which includes a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, it implements the data processing method of the multi-parameter interference fiber optic sensing system as described in the first aspect.

[0039] To achieve the above-mentioned purpose, the fourth aspect of an embodiment of the present application proposes a storage medium, which is a computer-readable storage medium and stores a computer program. When the computer program is executed by a processor, it implements the data processing method of the multi-parameter interference fiber optic sensing system described in the first aspect above.

[0040] The data processing method and related equipment of a multi-parameter interferometric fiber optic sensing system proposed in an embodiment of the present application, the multi-parameter interferometric fiber optic sensing system includes multiple interferometric fiber optic sensors, a synthetic wavelength division multiplexer and a spectrometer. The method includes: first, obtaining the interference spectrum of the interferometric fiber optic sensor, and determining the working band of each interferometric fiber optic sensor based on the interference spectrum, and the working bands between each two interferometric fiber optic sensors do not overlap; then, using a receiving wavelength division multiplexer to divide the target light source, and in each interferometric fiber optic sensor, using the corresponding working band to respond to the divided target light source to obtain physical parameter signals, and the physical parameter signals are different from each other; next, all physical parameter signals are input into the synthetic wavelength division multiplexer for synthesis processing to obtain a composite light signal; finally, the composite light signal is input into the spectrometer for analysis processing to obtain a multi-parameter analysis result of the target light source. The embodiments of the present application accurately analyze the inherent interference spectral characteristics of the interferometric fiber optic sensor itself and divide a unique, non-overlapping narrowband working band for each interferometric fiber optic sensor, thereby solving the problem of severe overlap and indistinguishability of spectral signals when multiple interferometric fiber optic sensors are used in a sensing system. The signals of multiple interferometric sensors can be effectively merged using a wavelength division multiplexer and demodulated in parallel and without crosstalk on the same spectrometer. The corresponding bands in the synthesized composite optical signal are analyzed using the pre-divided working bands to obtain changes in the external physical parameters of the corresponding target light source. The sensing system can then be used to accurately and simultaneously detect multiple physical parameters of the target light source, thereby improving the channel multiplexing capability and overall working efficiency of the sensing system, achieving efficient utilization of spectral resources, and expanding the application potential of high-sensitivity interferometric fiber optic sensors in the field of multi-point, multi-parameter distributed or quasi-distributed sensing. At the same time, it also helps to reduce the construction cost and complexity of complex sensing systems.

[0041] Other features and advantages of the present application will be described in the following description, and in part will become apparent from the description, or will be understood by practicing the present application. The purposes and other advantages of the present application can be achieved and obtained through the structures particularly pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 This is a structural diagram of a multi-parameter interferometric fiber optic sensing system provided in one embodiment of the present application.

[0043] Figure 2 This is a flowchart of a data processing method for a multi-parameter interferometric fiber optic sensing system provided in another embodiment of the present application.

[0044] Figure 3 yes Figure 2 Flowchart of step 201 in FIG.

[0045] Figure 4 yes Figure 3 Flowchart of step 302 in FIG.

[0046] Figure 5 yes Figure 2 Flowchart of step 202 in FIG.

[0047] Figure 6 This is a schematic diagram of wavelength bands of multiple wavelength division multiplexing sub-channels in a receiving wavelength division multiplexer provided in another embodiment of the present application.

[0048] Figure 7 yes Figure 5 Flowchart of step 501 in FIG.

[0049] Figure 8 yes Figure 2 Flowchart of step 203 in FIG.

[0050] Figure 9 yes Figure 2 Flowchart of step 204 in FIG.

[0051] Figure 10 This is a flow chart of a data processing method for a multi-parameter interferometric optical fiber sensing system provided in another embodiment of the present application.

[0052] Figure 11 This is a schematic diagram of the hardware structure of an electronic device provided in one embodiment of the present application. DETAILED DESCRIPTION

[0053] In order to make the purpose, technical solutions and advantages of this application more clear, the following further describes this application in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0054] It should be noted that although the functional modules are divided in the device schematic and the logical order is shown in the flowchart, in some cases, the steps shown or described can be performed in a different order than the module division in the device or the order in the flowchart.

[0055] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application pertains. The terms used herein are for the purpose of describing the embodiments of this application only and are not intended to limit this application.

[0056] In the field of fiber optic sensing, interferometric fiber optic sensors are widely used due to their high sensitivity and anti-electromagnetic interference advantages. In related technologies, when using interferometric fiber optic sensors (such as Fabry-Perot cavities, Mach-Zehnder interferometers and other structures) to detect physical quantities (such as pressure, temperature, etc.), a broadband light source is usually used to provide input light for a single interferometric sensor, and then a spectrometer is used to capture and analyze the interference spectrum output by the sensor, and the change of the external physical quantity is obtained based on the change of the interference optical path difference of the interference spectrum. However, when demodulating using a broadband light source and a spectrometer, the interference spectrum fringes of a single interferometric fiber optic sensor are usually distributed over a very wide wavelength range, and even occupy the entire spectrum of the broadband light source, resulting in only a single interferometric fiber optic sensor being used in a sensing system at the same time to analyze the change of a single physical quantity using the interference spectrum obtained by capture and analysis, which greatly limits the working efficiency of the interferometric fiber optic sensing system and causes a low utilization rate of spectral resources.

[0057] In order to improve the spectral resource utilization of the interferometric fiber optic sensing system, the embodiment of the present application accurately analyzes the inherent interference spectral characteristics of the interferometric fiber optic sensor itself and divides a unique, non-overlapping narrowband working band for each interferometric fiber optic sensor, thereby solving the problem of severe overlap and indistinguishability of spectral signals when multiple interferometric fiber optic sensors are used in the sensing system. The signals of multiple interferometric sensors can be effectively combined using a wavelength division multiplexer and demodulated in parallel and without crosstalk on the same spectrometer. The corresponding bands in the synthesized composite optical signal are analyzed using the pre-divided working bands to obtain the changes in the external physical parameters of the corresponding target light source. The sensing system can then be used to accurately and simultaneously detect multiple physical parameters of the target light source, thereby improving the channel multiplexing capability and overall working efficiency of the sensing system, achieving efficient utilization of spectral resources, and expanding the application potential of high-sensitivity interferometric fiber optic sensors in the field of multi-point, multi-parameter distributed or quasi-distributed sensing. At the same time, it also helps to reduce the construction cost and complexity of complex sensing systems.

[0058] In order to better illustrate the data processing method of the multi-parameter interferometric optical fiber sensing system provided by the embodiment of the present application, this embodiment first describes the multi-parameter interferometric optical fiber sensing system to which the data processing method is applied. Figure 1 As shown in FIG, it is a structural diagram of a multi-parameter interferometric optical fiber sensing system provided by an embodiment of the present application. Figure 1 As shown in the figure, the system consists of the following main parts: broadband light source, receiving wavelength division multiplexer (such as Figure 1 The wavelength division multiplexer device on the left), multiple interferometric fiber optic sensors, synthetic wavelength division multiplexers (such as Figure 1The WDM device on the right side of the center), the spectrometer, and the control processor.

[0059] The broadband light source is used to emit a target light source, and its spectral range must be wide enough to cover the unique operating bands assigned to all subsequent interferometric fiber optic sensors. The receiving wavelength division multiplexer is used to receive the optical signal from the broadband light source and, within its multiple wavelength division multiplexing sub-channels, divide the target light source into multiple varying sub-beams of specific wavelength bands, i.e., narrowband light, based on pre-determined, non-overlapping operating bands for each sensor. These light beams are then directed to their corresponding interferometric fiber optic sensors. Each interferometric fiber optic sensor, after receiving the varying sub-beams of the specific operating band, interacts with the physical quantity to be measured, generating a physical parameter signal carrying information about the physical quantity, i.e., a modulated optical signal. The synthesizing wavelength division multiplexer is used to receive the physical parameter signals from all interferometric fiber optic sensors in their independent operating bands and synthesize them into a single output optical fiber to form a composite optical signal. The spectrometer is used to receive and analyze the composite optical signal. Because the signals from each sensor occupy different spectral regions, the spectrometer can distinguish the signal changes in each channel, providing a basis for subsequent demodulation and ultimately obtaining multi-parameter analysis results. The entire system achieves efficient multiplexing and parallel demodulation of multi-path interference sensing signals through band division based on the sensor's own spectral characteristics and precise routing and merging of WDM devices.

[0060] The data processing method of the multi-parameter interferometric fiber optic sensing system provided in the embodiment of the present application can be applied to the control processor in the multi-parameter interferometric fiber optic sensing system, and can also be applied to the server, intelligent terminal, etc. connected to the multi-parameter interferometric fiber optic sensing system. Based on the above-mentioned multi-parameter interferometric fiber optic sensing system, the data processing method of the multi-parameter interferometric fiber optic sensing system in the embodiment of the present application will be described in detail below. Figure 2 , which is an optional flow chart of a data processing method for a multi-parameter interferometric optical fiber sensing system provided in an embodiment of the present application, Figure 2 The method may include but is not limited to steps 201 to 204. It is also understood that this embodiment is for Figure 2 The order of step 201 to step 204 is not specifically limited, and the order of steps can be adjusted or some steps can be reduced or added according to actual needs.

[0061] Step 201: Obtain an interference spectrum of an interferometric optical fiber sensor, and determine an operating band of each interferometric optical fiber sensor based on the interference spectrum.

[0062] Step 201 is described in detail below.

[0063] In some embodiments, when measuring and analyzing changes in multiple external physical parameters of a broadband light source in response to a multi-parameter interferometric fiber optic sensing system, the interference spectrum of each interferometric fiber optic sensor is first obtained. The interference spectrum refers to the spectral distribution of the optical signal output by the interferometric fiber optic sensor (such as a Fabry-Perot (FP) sensor, a Mach-Zehnder interferometer (MZI), or a Sagnac interferometer). It is characterized by having a series of peaks and valleys, the positions and intensities of which vary with the changes in the measured physical quantity, and can be obtained using a spectrometer or other device; then, based on the obtained interference spectrum, the operating band of each interferometric fiber optic sensor is determined, and the operating bands between each two interferometric fiber optic sensors do not overlap. The operating band refers to the specific wavelength range used by the interferometric fiber optic sensor to sense a specific physical quantity. Since the structure and parameters of each interferometric fiber optic sensor are different, the characteristics of its interference spectrum are also different. Therefore, it is necessary to determine its operating band based on the interference spectrum characteristics of each sensor. The purpose is to ensure that each sensor operates within its specific wavelength range, thereby avoiding signal interference between different sensors.

[0064] Reference Figure 3 , obtaining the interference spectrum of the interferometric fiber optic sensor, and determining the working band of each interferometric fiber optic sensor based on the interference spectrum, including the following steps 301 to 303.

[0065] Step 301: Perform spectrum measurement on the interferometric optical fiber sensor in an atmospheric environment to obtain an interference spectrum.

[0066] Step 302: Determine a plurality of non-overlapping interference sub-bands in the interference spectrum based on the phase difference between each two light beams.

[0067] Steps 301 to 302 are described in detail below.

[0068] In some embodiments, in order to assign a suitable and non-overlapping working band to each interferometric fiber optic sensor, the interferometric fiber optic sensor is first placed in a clear and usually easy-to-reproduce reference environment, that is, an atmospheric environment, and a spectral measurement is performed on it. The atmospheric environment here usually refers to laboratory or field reference conditions such as standard atmospheric pressure and room temperature, and is intended to obtain the basic optical response characteristics of the sensor in the absence of strong disturbances of specific external physical quantities. The spectral measurement process specifically involves: using a broadband light source that can cover the expected working wavelength range to inject an optical signal into the interferometric fiber optic sensor, and using a high-resolution spectral analysis device (such as a spectrometer OSA) to accurately receive and record the detailed distribution of the intensity of the optical signal output from the sensor as it varies with wavelength, thereby obtaining the interference spectrum of the sensor in this reference state.

[0069] For the i-th interferometric fiber optic sensor, assuming that the total number of light beams involved in the interference is n, the interference spectrum of the interferometric fiber optic sensor has a relationship expression as shown in the following formula (1).

[0070]

[0071] Where I0 is the intensity of a single beam, which indicates the intensity of each beam and is usually proportional to the square of the beam amplitude; φ is the beam phase, which indicates the phase information of the beam; cos(φ j -φ k ) The cosine value of the phase difference between each two light beams (such as the phase difference between the j-th and k-th light beams) reflects their coherence and interference effect.

[0072] Next, based on the phase difference between every two light beams in the interference spectrum, a plurality of non-overlapping interference sub-bands in the interference spectrum of the interferometric optical fiber sensor are determined, as described in detail below.

[0073] Reference Figure 4 , based on the phase difference between each two light beams, determining multiple non-overlapping interference sub-bands in the interference spectrum, including the following steps 401 to 402.

[0074] Step 401: taking each two light beam phases as a test phase one by one, and when the phase difference of the test phases is a preset angle, taking the wavelength values corresponding to the two light beam phases corresponding to the test phases as a trough wavelength pair.

[0075] Step 402: obtaining candidate wavelength pairs based on all trough wavelength pairs, and selecting non-overlapping trough wavelength pairs from all candidate wavelength pairs to obtain interferometer bands.

[0076] Steps 401 to 402 are described in detail below.

[0077] In some embodiments, during the interference process between light beams, the phase difference between the beams determines their coherence, thereby affecting the intensity of the interference fringes. When the phase difference is zero, the interference between the beams is maximized, and the light intensity reaches its maximum. When the phase difference is π, the beams cancel each other out, and the light intensity is zero. The light intensity exhibits periodic variations as the phase difference changes.

[0078] Based on this, each two light beam phases are used as test phases one by one. When the phase difference of the test phases is a preset angle, the wavelength values corresponding to the two light beam phases corresponding to the test phases are used as trough wavelength pairs. "Beam phase" refers to the phase information of the two light beams participating in the interference in the interference spectrum. Combining each two light beam phases in pairs to form a "test phase" is to traverse all possible combinations of light beam phases. "Preset angle" refers to the pre-set optical path difference of the light beams, which is used to determine the trough position of the interference fringes. When the phase difference of the test phases is equal to the preset angle, it is considered that the wavelength values corresponding to the two light beam phases are located at the trough position of the interference spectrum, and the two wavelength values are recorded as a "trough wavelength pair".

[0079] Then, candidate wavelength pairs are obtained based on all trough wavelength pairs, and non-overlapping trough wavelength pairs are selected from all candidate wavelength pairs to obtain interference sub-bands. Since there may be multiple troughs in an interference spectrum, multiple trough wavelength pairs are obtained, and these wavelength pairs constitute a set of "candidate wavelength pairs." To avoid spectral overlap and interference between the operating bands of different sensors, non-overlapping trough wavelength pairs need to be selected from the candidate wavelength pairs. These selected, non-overlapping trough wavelength pairs define multiple "interference sub-bands" in the interference spectrum. Each interference sub-band corresponds to a specific wavelength range, and its spectral characteristics are suitable for subsequent signal demodulation and analysis. There is no overlap between different sub-bands, ensuring the independence of each sensor signal during multi-parameter measurement.

[0080] That is, the stable interference segments in the fringes of the interference spectrum where "a clear peak is contained between two adjacent troughs" are identified. For the i-th interferometric fiber optic sensor, there are multiple trough wavelength pairs as shown in the following formula (2).

[0081] λ i,start <λ i,c <λ i,end (2)

[0082] Among them, λ i,start is the trough wavelength value corresponding to the left trough in the trough wavelength pair, λ i,c is the peak wavelength value corresponding to the peak in the trough wavelength pair, λ i,end is the trough wavelength value corresponding to the right trough in the trough wavelength pair.

[0083] Step 303: Selecting a different interference sub-band for each interferometric optical fiber sensor as the working band of the interferometric optical fiber sensor.

[0084] Step 303 is described in detail below.

[0085] In some embodiments, after determining multiple non-overlapping interference sub-bands in the interference spectrum of the interferometric fiber optic sensor, a different interference sub-band is selected for each interferometric fiber optic sensor as its operating band. That is, for the i-th interferometric fiber optic sensor, non-overlapping interference sub-bands are selected as its operating band to ensure that no spectral interference will occur when the sensor is subsequently used in parallel. The corresponding conditions for satisfying these conditions are shown in the following formula (3).

[0086]

[0087] Then record the band bandwidth Δλ of its working band i is Δλ i =λ i,start -λ i,end , and the peak wavelength is λ i,c .

[0088] Through the above steps 301 to 303, and steps 401 to 402, by performing spectral measurements in a standard atmospheric environment, the representativeness and stability of the obtained reference interference spectrum are ensured. Innovatively, the method does not directly rely on macroscopic observation of the spectral shape, but instead deeply analyzes the fundamental physical quantity that constitutes interference, namely the phase difference between each two light beam phases. By setting a clear criterion (determining the trough wavelength pair when the phase difference is a preset angle, step 401), the potential interference sub-band boundaries (spectral troughs) are accurately located. Then, through systematic screening, it is ensured that the trough wavelength pairs selected for defining the interference sub-bands do not overlap with each other in the spectrum, thereby ensuring the independence of the candidate bands. By clearly selecting a different interference sub-band as the operating band for each interferometric fiber optic sensor, a conflict-free spectral resource allocation scheme is successfully constructed. This method not only improves the accuracy and reliability of band selection, but more importantly, it fundamentally solves the core problem of the existing technology that the serious overlap of multi-sensor spectra leads to the inability to effectively reuse. It can significantly improve the channel capacity and spectral utilization efficiency of the multi-parameter interferometric sensing system based on wavelength division multiplexing, and lay a solid technical foundation for the realization of large-scale, high-efficiency distributed or quasi-distributed interferometric sensing applications.

[0089] Step 202: using a receiving wavelength division multiplexer to divide the target light source, and in each interferometric optical fiber sensor, using a corresponding working wavelength band to respond to the divided target light source to obtain a physical parameter signal.

[0090] Step 202 is described in detail below.

[0091] In some embodiments, after assigning a corresponding operating wavelength band to each interferometric fiber optic sensor, a receiving wavelength division multiplexer receives a target light source, divides the target light source using its internal wavelength division multiplexing sub-channels, and then inputs the divided target light source into each corresponding interferometric fiber optic sensor. Each interferometric fiber optic sensor operates only within its previously assigned, dedicated operating wavelength band, responding to the divided target light source using optical signals within that specific wavelength band, thereby obtaining a physical parameter signal carrying information about changes in the corresponding physical quantity. Because each sensor has a unique operating wavelength band, the generated physical parameter signal also independently reflects the changing state of its corresponding physical parameter, as described below.

[0092] Reference Figure 5 , using a receiving wavelength division multiplexer to divide the target light source, and in each interferometric optical fiber sensor, using the corresponding working band to respond to the divided target light source to obtain a physical parameter signal, including the following steps 501 to 502.

[0093] Step 501: For each interferometric fiber optic sensor, a wavelength division multiplexing sub-channel having a center wavelength matching the operating band is selected from multiple wavelength division multiplexing sub-channels of a receiving wavelength division multiplexer using the corresponding operating band as the matching sub-channel of the interferometric fiber optic sensor, and the interferometric fiber optic sensor is connected to the corresponding matching sub-channel.

[0094] Step 501 is described in detail below.

[0095] In some embodiments, before measuring a target light source, for each interferometric fiber optic sensor, a wavelength division multiplexing (WDM) sub-channel whose center wavelength matches the operating band is selected from the multiple WDM sub-channels of a receiving WDM multiplexer using its corresponding operating band as the interferometric fiber optic sensor's matching sub-channel. The interferometric fiber optic sensor is then connected to the corresponding matching sub-channel. The receiving WDM multiplexer contains multiple "WDM sub-channels," each of which allows light signals within a specific wavelength range to pass through. "Center wavelength" refers to the center wavelength of the light signals allowed through each WDM sub-channel. A "matching sub-channel" refers to a WDM sub-channel whose center wavelength matches the sensor's operating band. By connecting each sensor to its matching sub-channel, the optical signal received by the sensor is ensured to be within its operating band, thereby achieving efficient multi-parameter measurement. Specifically, each sensor is connected to the sub-channel of the receiving WDM multiplexer that corresponds to its operating band, ensuring that the sensor receives light of the correct wavelength for measurement.

[0096] Reference Figure 6 , is a schematic diagram of a wavelength band of multiple wavelength division multiplexing sub-channels in a receiving wavelength division multiplexer provided by an embodiment of the present application. Figure 6As shown in the figure, it represents the output spectrum of multiple wavelength division multiplexing sub-channels in the receiving wavelength division multiplexer, showing the wavelength distribution of each wavelength division multiplexing sub-channel. c,i Corresponding to different wavelength division multiplexing sub-channels in the receiving wavelength division multiplexer, the interval between the center wavelengths of each wavelength division multiplexing sub-channel is visible, and there is no overlap between the wavelengths, ensuring that each channel works independently in a different frequency band and avoiding interference between signals.

[0097] The following will further describe how to select a corresponding matching sub-channel for each interferometric fiber optic sensor.

[0098] Reference Figure 7 For each interferometric fiber optic sensor, a wavelength division multiplexing sub-channel whose center wavelength matches the working band is selected from multiple wavelength division multiplexing sub-channels of a receiving wavelength division multiplexer using the corresponding working band as the matching sub-channel of the interferometric fiber optic sensor, including the following steps 701 to 702.

[0099] Step 701: Use each interferometric optical fiber sensor as a matching sensor one by one.

[0100] Step 702: Select a wavelength division multiplexing sub-channel from multiple wavelength division multiplexing sub-channels, whose difference between the center wavelength and the peak wavelength is less than a preset tolerance value and whose channel bandwidth is greater than the band bandwidth, as a matching sub-channel corresponding to the matching sensor.

[0101] Steps 701 to 702 are described in detail below.

[0102] In some embodiments, each interferometric fiber optic sensor is individually selected as a matching sensor. Here, a "matched sensor" refers to the interferometric fiber optic sensor currently being matched to a wavelength division multiplexing (WDM) sub-channel. This step is intended to clearly identify the sensor currently being matched to a WDM sub-channel, ensuring that each sensor is correctly connected to the corresponding sub-channel.

[0103] Next, a wavelength division multiplexing sub-channel whose difference between the center wavelength and the peak wavelength is less than the preset tolerance value and whose channel bandwidth is greater than the band bandwidth is selected from multiple wavelength division multiplexing sub-channels as the matching sub-channel corresponding to the matching sensor. The "preset tolerance value" refers to the maximum deviation allowed between the center wavelength and the peak wavelength, which is usually determined by the accuracy requirements of the system and the performance parameters of the device. The purpose of this step is to select a wavelength division multiplexing sub-channel that best matches the operating band of the sensor. The selection criteria are: the center wavelength of the sub-channel should be as close as possible to the peak wavelength of the sensor operating band (the difference is less than the preset tolerance value), and the bandwidth of the sub-channel should be wide enough to cover the entire sensor operating band (the channel bandwidth is greater than the band bandwidth). This ensures that the sensor operates within its most sensitive wavelength range and obtains the best signal-to-noise ratio.

[0104] That is, according to the working band of the interferometric fiber optic sensor after screening, the wavelength division multiplexing sub-channel of the receiving wavelength division multiplexer is matched appropriately. The center wavelength of the WDM channel corresponding to the i-th sensor satisfies the following screening formula (4).

[0105] |λ i,WDM -λ i,c |<ε,Δλ i,WDM >Δλ i (4)

[0106] Among them, λ i,WDM is the central wavelength of the wavelength division multiplexing sub-channel (i.e., matching sub-channel) corresponding to the i-th interferometric fiber optic sensor in the receiving wavelength division multiplexer; Δλ i,WDM is the channel bandwidth of the wavelength division multiplexing sub-channel (i.e., matching sub-channel) corresponding to the i-th interferometric fiber optic sensor in the receiving wavelength division multiplexer; ε is the preset tolerance value, which refers to the allowable wavelength deviation and is usually set according to the accuracy of the device and the requirements of the system.

[0107] In addition, to avoid cross-interference between signals, the channel bandwidth of each wavelength division multiplexing sub-channel in the receiving wavelength division multiplexer should be designed to be non-overlapping.

[0108] Step 502: After each matching sub-channel in the receiving wavelength division multiplexer receives the target light source, the target light source is divided using the corresponding working band to obtain a changing sub-beam corresponding to each matching sub-channel, and the changing sub-beam is transmitted to the corresponding interferometric fiber optic sensor.

[0109] 503: In each interferometric optical fiber sensor, a corresponding operating wavelength band is used to respond to the changing sub-beam to obtain a physical parameter signal.

[0110] Steps 502 to 503 are described in detail below.

[0111] In some embodiments, after each interferometric fiber optic sensor is matched with a wavelength division multiplexing subchannel (i.e., a matching subchannel) of a receiving wavelength division multiplexer, when light from a target light source enters the receiving wavelength division multiplexer, the device, based on its internal spectral separation mechanism, divides the target light source within each matching subchannel using its corresponding operating wavelength band, generating a corresponding variable sub-beam. Because the center wavelength of the matching subchannel matches the operating wavelength band, each matching subchannel outputs only a specific narrowband spectrum near its corresponding center wavelength. This separated variable sub-beam corresponding to the specific matching subchannel is then accurately transmitted to the corresponding interferometric fiber optic sensor previously connected to the matching subchannel. Once the light signal reaches the interferometric fiber optic sensor, it responds using this variable sub-beam of a specific wavelength, allowing the light to interact with the physical quantity to be measured in the sensor's environment, resulting in changes in the light's characteristics (e.g., phase, interference fringe position). Ultimately, the modulated light signal output from the interferometric fiber optic sensor, which carries the sensing information, is defined as a physical parameter signal. This process occurs in parallel for each sensor in the system and its corresponding matching sub-channel, achieving the preliminary generation of multi-path sensor signals.

[0112] Through the above steps 501 to 503, and steps 701 to 702, a rigorous matching process ensures that each interferometric fiber optic sensor can be accurately connected to the matching sub-channel on the receiving wavelength division multiplexer that best suits its operating band characteristics. This ensures that each sensor only receives the most effective spectral components "tailored" for it, effectively distributing the light energy of the broadband target light source on demand. The receiving wavelength division multiplexer generates spectrally pure and independent varying sub-light beams corresponding to each matching sub-channel. This not only maximizes the utilization efficiency of the light source but also avoids input light crosstalk between different sensors at the source. These precisely separated varying sub-light beams are then introduced into their respective corresponding interferometric fiber optic sensors for detection, ensuring that each sensor operates within its optimized operating band, thereby generating high-quality, clear signals of the physical parameter signals that are naturally isolated from each other in the spectral domain. This lays a solid foundation for subsequent crosstalk-free signal merging and precise demodulation, greatly improving the reliability and performance of the entire multi-parameter sensing system.

[0113] In addition, in order to measure and analyze the changes in multiple physical parameters, different interferometric fiber optic sensors are connected to corresponding wavelength division multiplexing sub-channels. Each wavelength division multiplexing sub-channel is used to monitor a physical parameter (such as pressure, temperature, vibration, etc.). The corresponding physical parameter change model is constructed for each physical parameter.

[0114] If the physical parameter of the ith fiber interferometric sensor response is ai This response will cause the drift of the spectral fringes, that is, the phenomenon of the waveform shifting in the spectrometer. There is a functional relationship between the two as shown in the following formula (5).

[0115]

[0116] Among them, n i is the optical fiber refractive index of the i-th wavelength division multiplexing sub-channel; ΔL is the change of the optical path difference, which comes from changes in external factors such as temperature, pressure, refractive index, etc.

[0117] Based on this, ΔL(a i )The change in optical path difference corresponding to each physical parameter.

[0118] When the physical parameter is temperature, temperature changes will alter the physical dimensions or refractive index of the optical fiber, thereby affecting the optical path difference. Assuming the linear expansion coefficient of the optical fiber is α and the original length of the optical fiber is L0, the change in optical path difference due to temperature change ΔT can be expressed as shown in the following formula (6).

[0119] ΔL(ΔT)=αL0·ΔT (6)

[0120] When the physical parameter is pressure, pressure changes can alter the optical path difference by affecting the refractive index of the optical fiber or the physical dimensions of the optical fiber material (e.g., the length or diameter of the optical fiber). Assuming the bulk modulus of the optical fiber material is B, the change in optical path difference due to an externally applied pressure change ΔP can be expressed as shown in the following formula (7).

[0121]

[0122] When the physical parameter is the refractive index, changes in the refractive index are also a key factor affecting the optical path difference. Chemical changes in the environment may cause changes in the optical fiber's refractive index n. Assuming the change in refractive index is Δn, the change in optical path difference can be expressed as shown in the following formula (8).

[0123]

[0124] Step 203: All physical parameter signals are input into a synthesizing wavelength division multiplexer for synthesis processing to obtain a composite optical signal.

[0125] Step 203 is described in detail below.

[0126] In some embodiments, after multiple interference fiber optic sensors measure the corresponding physical parameters of the changing sub-light beams to obtain physical parameter signals, the multiple physical parameter signals are input into a synthesizing wavelength division multiplexer for synthesis processing to obtain a composite light signal, so that the corresponding bands in the synthesized composite light signal can be analyzed using pre-divided working bands. The changes in the external physical parameters of the corresponding target light source can be analyzed, so that the sensing system can be used to accurately and simultaneously detect multiple physical parameters of the target light source. The synthesis process is specifically described as follows.

[0127] Reference Figure 8 , all physical parameter signals are input into the synthesizing wavelength division multiplexer for synthesis processing to obtain a composite optical signal, including the following steps 801 to 802.

[0128] Step 801: In a synthesizing wavelength division multiplexer, the fiber index parameter corresponding to each physical parameter signal is obtained by performing index processing based on the product of the fiber attenuation coefficient and the fiber transmission length of each physical parameter signal.

[0129] Step 801: Accumulate the product of the fiber index parameter and the light intensity of each physical parameter signal to obtain a composite optical signal.

[0130] Steps 801 to 802 are described in detail below.

[0131] In some embodiments, in the synthetic wavelength division multiplexer, the optical fiber attenuation coefficient α of each physical parameter signal (such as the i-th signal) is respectively i (λ) and fiber transmission length S i The product of , and then perform index processing to obtain the fiber index parameter corresponding to each physical parameter signal (such as the i-th) Then, the product of the fiber index parameter and the light intensity of each physical parameter signal is accumulated to obtain a composite optical signal, as shown in the following formula (9).

[0132]

[0133] Where N is the number of interferometric fiber optic sensors; α(λ) is the wavelength-dependent fiber attenuation coefficient (usually in functional form, taking into account transmission losses at different wavelengths); and S is the transmission length of the fiber.

[0134] Through steps 801 to 802 above, the physical parameter signals of each sensor are synthesized into a composite optical signal by taking into account the losses during optical fiber transmission, so that they can be subsequently demodulated and analyzed on a single spectrometer. For each physical parameter signal, a fiber index parameter is calculated based on its fiber attenuation coefficient and fiber transmission length. This parameter reflects the degree of attenuation of the optical signal during optical fiber transmission. The light intensity of each physical parameter signal is multiplied by its corresponding fiber index parameter and then added together to obtain the final composite optical signal. This synthesis method effectively compensates for the impact of optical fiber transmission losses on measurement results, improves measurement accuracy, and simplifies the system structure. Multiple parameters can be analyzed simultaneously using only a single spectrometer.

[0135] Step 204: Input the composite light signal into the spectrometer for analysis and processing to obtain a multi-parameter analysis result of the target light source.

[0136] Step 204 is described in detail below.

[0137] In some embodiments, after obtaining the composite light signal, the composite light signal is input into a spectrometer for analysis and processing, and Δλ is obtained by analyzing the changes in the interference fringes in each band. i,c , the parameter values can be inversely solved according to the previous physical parameter change model, thereby achieving the multi-parameter analysis results corresponding to the parallel monitoring and analysis of multiple physical parameters of the target light source, as described below.

[0138] Reference Figure 9 , inputting the composite light signal into the spectrometer for analysis and processing to obtain a multi-parameter analysis result of the target light source, including the following steps 901 to 904.

[0139] Step 901: In a spectrometer, each operating wavelength band in the composite optical signal is analyzed separately to obtain a variation of interference fringes.

[0140] Step 902: Obtain the optical path difference variation of the physical parameter corresponding to the working band based on the product of the interference fringe variation and the fiber refractive index of the matching sub-channel corresponding to the working band, and then dividing by the peak wavelength of the working band.

[0141] Step 903: Obtain parameter analysis results corresponding to physical parameters corresponding to the working band based on the optical path difference variation.

[0142] Step 904: Based on the parameter analysis results corresponding to all physical parameters, a multi-parameter analysis result of the target light source is obtained.

[0143] Steps 901 to 904 are described in detail below.

[0144] In some embodiments, in the spectrometer, the spectrometer will independently analyze each predefined working band contained in the received composite light signal. Since the previous band selection and receiving wavelength division multiplexer processing ensure that these working bands are spectrally separated, the spectrometer can clearly identify and isolate the spectral information within each working band. The core of the analysis is to quantify the changes that occur in the sensing process, that is, to accurately measure the displacement of the interference spectrum characteristics (such as the peak or trough position) relative to the reference position due to the influence of external physical quantities in the working band. This displacement is defined as the interference fringe change, that is, Δλ i,c , usually expressed in wavelength units (such as nanometers nm).

[0145] Then, combined with the above physical parameter change model (5), based on the interference fringe change Δλ i,c The fiber refractive index n of the matching sub-channel corresponding to the working band i The product of the peak wavelength λ of the working band is divided by i,c , the optical path difference variation of the physical parameter corresponding to each working band in the composite optical signal is obtained, as shown in the following formula (10).

[0146]

[0147] Then, based on the optical path difference variation formula corresponding to each physical parameter (such as the above formulas (5)-(7)), the parameter analysis result a corresponding to the physical parameter corresponding to the working band is obtained based on the optical path difference variation of each working band. i ; and based on the parameter analysis results corresponding to all physical parameters, the multi-parameter analysis results of the target light source are obtained.

[0148] Through the above steps 901 to 904, by independently analyzing each working band in the spectrometer and obtaining the interference fringe variation, the advantage of the previously carefully designed non-overlapping working bands is utilized to ensure the effective separation and crosstalk-free processing of multi-channel signals in the demodulation stage. Then, combined with the pre-built physical parameter change model, the observed spectral domain changes (interference fringe variation) are combined with key system parameters (fiber refractive index, peak wavelength) to be converted into a more basic optical path difference variation that is directly related to the physical quantity, thereby improving the accuracy of the intermediate calculation and the clarity of the physical meaning. Then, based on the optical path difference variation, the optical path difference variation is obtained. The parameter analysis results corresponding to specific physical parameters realize the final conversion from optical measurement quantities to physical quantities required for actual engineering or science, making the measurement results have direct application value. By summarizing the parameter analysis results corresponding to all physical parameters, it is possible to generate multi-parameter analysis results of the target light source that comprehensively reflects the environmental status monitored by the system. This series of coherent and rigorous processing steps not only ensures the accurate and reliable extraction of multi-channel sensing information, but also reflects the integrity and efficiency of the entire system from signal multiplexing and transmission to final demodulation, ultimately improving the overall performance and practical value of the multi-parameter interferometric fiber optic sensing system.

[0149] Reference Figure 10 , is a flow chart of a data processing method for a multi-parameter interferometric optical fiber sensing system provided in an embodiment of the present application. Figure 10 As shown in the figure, the complete data processing process of the multi-parameter interferometric fiber optic sensing system is presented. The process begins with the initial spectral observation of each interferometric fiber optic sensor in a standard atmospheric environment, measures its interference spectrum with a spectrometer, analyzes and selects a clear-featured "trough-peak-trough" interference fringe segment, and records the key wavelength (such as the left trough λ i,start , peak λ i,c , right trough λ i,end ) as the benchmark for subsequent processing; followed by the core band division step, carefully selecting a non-overlapping interference sub-band for each sensor in the system as its exclusive working band, and recording its bandwidth Δλ i , and strictly ensure that the working band intervals of any two sensors meet the isolation conditions to avoid spectral interference when used in parallel later; then perform wavelength division multiplexer band matching, based on the previously determined working band of each sensor (especially the peak wavelength λ i,c ), for accurately selecting a matching sub-channel in the receiving wavelength division multiplexer (WDM). The key criterion for selection is the central wavelength of the WDM sub-channel and the sensor peak wavelength λ i,c The deviation is within the allowable tolerance range, and the channel bandwidth Δλ of the WDM subchannel i,WDM Must be greater than the sensor's operating band bandwidth Δλ i (i.e. Δλi,WDM >Δλ i ), thereby ensuring that the signal can pass through completely and stably and that the channels are independent of each other; the next step is to establish a multi-physical parameter model. After each sensor is connected to its matching WDM channel, it is used to monitor specific physical quantities (such as pressure, temperature, refractive index, etc.), and the changes in external physical quantities (a i ) will cause the optical path difference ΔL of the sensor to change, which in turn causes the peak wavelength on its spectrum to drift Δλ i,c This step aims to establish the physical quantity a i , optical path difference ΔL and wavelength drift Δλ i,c The precise mathematical model relationship between them provides a basis for subsequent demodulation; finally, in the signal synthesis and spectral demodulation stage, the physical parameter signals from all sensors carrying their own physical quantity information are combined into a composite optical signal through a synthetic wavelength division multiplexer. The signal is sent to the spectrometer for detection. The spectrometer analyzes the interference fringe changes in the corresponding working band of each sensor in the composite optical signal (i.e., real-time monitoring of Δλ i,c ), combined with the previously established mathematical model, the physical value corresponding to each channel can be calculated in real time, ultimately enabling efficient parallel monitoring of multiple physical parameters. The entire process clearly demonstrates the complete technical path from sensor characterization, intelligent spectral resource allocation, precise optical path configuration, physical model establishment, and ultimately, multi-channel signal parallel demodulation.

[0150] The band selection and wavelength division multiplexing technology proposed in this solution significantly improves spectral resource utilization efficiency, enabling the realization of a multi-channel, configurable, multi-parameter sensing system using a single broadband light source and spectrometer. This technology screens the interference spectrum of each interferometric fiber sensor and precisely allocates non-overlapping bands within the spectrum, allowing each sensing channel to operate independently within its dedicated sub-band without interfering with each other. Furthermore, the system features adaptive band spacing adjustment, enabling dynamic configuration based on the number of physical quantities to be measured in the application scenario. When monitoring a small number of physical quantities, the center wavelength spacing between bands can be appropriately increased to enhance channel isolation and improve signal stability. In scenarios requiring the monitoring of multiple physical quantities, the band spacing can be reduced, compressing the bandwidth allocation to accommodate more sensing channels and maintain the overall system's high throughput. Therefore, this approach is not only suitable for static or low-channel-count single-point monitoring, but can also be flexibly expanded to high-channel-count, multi-point distributed large-scale IoT sensing networks, providing a highly integrated, scalable, and low-cost solution for simultaneous sensing of multiple physical quantities in complex environments.

[0151] The data processing method and related equipment of the multi-parameter interferometric fiber optic sensing system proposed in the embodiment of the present application, the multi-parameter interferometric fiber optic sensing system includes multiple interferometric fiber optic sensors, a synthetic wavelength division multiplexer and a spectrometer, the method includes: first, the interferometric fiber optic sensor is subjected to spectral measurement in an atmospheric environment to obtain an interference spectrum, the interference spectrum includes the beam phases of multiple light beams, each two light beam phases are used as test phases one by one, when the phase difference of the test phases is a preset angle, the wavelength values corresponding to the two light beam phases corresponding to the test phases are used as trough wavelength pairs, and candidate wavelength pairs are obtained based on all trough wavelength pairs, and Non-overlapping trough wavelength pairs are selected from all candidate wavelength pairs to obtain interference sub-bands. Different interference sub-bands are selected for each interferometric fiber optic sensor as the working band of the interferometric fiber optic sensor, and the working bands between each two interferometric fiber optic sensors do not overlap. Then, each interferometric fiber optic sensor is used as a matching sensor one by one, and a wavelength division multiplexing sub-channel whose difference between the center wavelength and the peak wavelength is less than a preset tolerance value and whose channel bandwidth is greater than the band bandwidth is selected from multiple wavelength division multiplexing sub-channels as the matching sub-channel corresponding to the matching sensor, and the interferometric fiber optic sensor is connected to the corresponding matching sub-channel. After each matching sub-channel in the receiving wavelength division multiplexer receives the target light source, the target light source is divided using the corresponding working band to obtain the changing sub-beam corresponding to each matching sub-channel, and the changing sub-beam is transmitted to the corresponding interferometric fiber optic sensor. In each interferometric fiber optic sensor, the changing sub-beam is responded to using the corresponding working band to obtain a physical parameter signal, which is different from each other. Next, in the synthesizing wavelength division multiplexer, the fiber index corresponding to each physical parameter signal is obtained by performing index processing based on the product of the fiber attenuation coefficient and the fiber transmission length of each physical parameter signal. Parameters are calculated, and the product of the fiber index parameter and the light intensity of each physical parameter signal is accumulated to obtain a composite optical signal; finally, in the spectrometer, each working band in the composite optical signal is analyzed separately to obtain a change in the interference fringe, and the product of the interference fringe change and the fiber refractive index of the matching sub-channel corresponding to the working band is divided by the peak wavelength of the working band to obtain a change in the optical path difference of the physical parameter corresponding to the working band, and the parameter analysis result corresponding to the physical parameter corresponding to the working band is obtained based on the change in the optical path difference, and the multi-parameter analysis result of the target light source is obtained based on the parameter analysis results corresponding to all physical parameters.

[0152] The embodiment of the present application accurately analyzes the inherent interference spectral characteristics of the interferometric fiber optic sensor itself and divides a unique, non-overlapping narrowband working band for each interferometric fiber optic sensor, thereby solving the problem of severe overlap and indistinguishability of spectral signals when multiple interferometric fiber optic sensors are used in the sensing system, so that the signals of multiple interferometric sensors can be effectively merged using a wavelength division multiplexer, and parallel, crosstalk-free demodulation can be achieved on the same spectrometer. In addition, the corresponding bands in the synthesized composite optical signal are analyzed using the pre-divided working bands, and the changes in the external physical parameters of the corresponding target light source can be analyzed, so that the sensing system can be accurately used to detect multiple physical parameters of the target light source at the same time, thereby improving the channel multiplexing capability and overall working efficiency of the sensing system, realizing efficient utilization of spectral resources, and expanding the application of high-sensitivity interferometric fiber optic sensors in multiple points and multiple parameters. The invention has the potential for application in the field of distributed or quasi-distributed sensing, and also helps to reduce the construction cost and complexity of complex sensing systems. In addition, by performing spectral measurements in a standard atmospheric environment, the representativeness and stability of the obtained reference interference spectrum are ensured. In an innovative way, the invention does not directly rely on the macroscopic observation of the spectral shape, but instead deeply analyzes the fundamental physical quantity that constitutes the interference, that is, the phase difference between each two light beam phases. By setting a clear criterion (determining the trough wavelength pair when the phase difference is a preset angle, step 401), the accurate positioning of the potential interference sub-band boundary (spectral trough) is achieved. Then, through systematic screening, it is ensured that the trough wavelength pairs selected for defining the interference sub-band do not overlap with each other in the spectrum, thereby ensuring the independence of the candidate bands. By clearly selecting a different interference sub-band as its working band for each interferometric fiber optic sensor, a conflict-free spectral resource allocation scheme is successfully constructed. This approach not only improves the accuracy and reliability of band selection but, more importantly, fundamentally addresses the core problem of existing technologies, which is the inability to effectively reuse multiple sensors due to severe spectral overlap. This significantly increases the channel capacity and spectral utilization efficiency of multi-parameter interferometric sensing systems based on wavelength division multiplexing, laying a solid technical foundation for large-scale, highly efficient distributed or quasi-distributed interferometric sensing applications.Moreover, through a strict matching process, it is ensured that each interferometric fiber optic sensor can be accurately connected to the matching sub-channel on the receiving wavelength division multiplexer that is most suitable for its working band characteristics, thereby ensuring that each sensor only receives the most effective spectral components "tailor-made" for it, so as to effectively distribute the light energy of the broadband target light source on demand, and generate spectrally pure and independent changing sub-light beams corresponding to each matching sub-channel through the receiving wavelength division multiplexer. This not only maximizes the utilization efficiency of the light source, but also avoids the input light crosstalk between different sensors from the source, and then these precisely separated changing sub-light beams are respectively introduced into their corresponding interferometric fiber optic sensors for detection, which can ensure that each sensor is in its optimized working state. The system operates within the same wavelength band, thereby generating high-quality, clear-signal physical parameter signals that are naturally isolated from each other in the spectral domain, laying a solid foundation for subsequent crosstalk-free signal merging and precise demodulation, and greatly improving the reliability and performance of the entire multi-parameter sensing system; and, by considering the loss in the optical fiber transmission process, the physical parameter signals of each sensor are synthesized into a composite optical signal for subsequent demodulation and analysis on a single spectrometer. For each physical parameter signal, the optical fiber index parameter is calculated based on its optical fiber attenuation coefficient and optical fiber transmission length. This parameter reflects the attenuation degree of the optical signal during optical fiber transmission. The light intensity of each physical parameter signal is multiplied by its corresponding optical fiber index parameter and then accumulated. The final composite optical signal is obtained by adding the optical fibers together. This synthesis method effectively compensates for the influence of optical fiber transmission loss on the measurement results, improves the measurement accuracy, and simplifies the system structure. Only one spectrometer is needed to analyze multiple parameters at the same time. In addition, by independently analyzing each working band in the spectrometer and obtaining the interference fringe change, the advantage of the previously carefully designed non-overlapping working bands is utilized to ensure the effective separation and crosstalk-free processing of multiple signals in the demodulation stage. Combined with the pre-built physical parameter change model, the observed spectral domain changes (interference fringe changes) are combined with key system parameters (fiber refractive index, peak wavelength) to be converted into a more basic optical path difference change that is directly related to the physical quantity, thereby improving the optical path difference. The accuracy of intermediate calculations and the clarity of physical meaning are ensured. By deriving parameter analysis results corresponding to specific physical parameters based on the change in optical path difference, the final conversion from optical measurement quantities to physical quantities required for practical engineering or scientific research is achieved, making the measurement results directly applicable. By summarizing the parameter analysis results corresponding to all physical parameters, a multi-parameter analysis result of the target light source can be generated that comprehensively reflects the environmental state monitored by the system. This series of coherent and rigorous processing steps not only ensures the accurate and reliable extraction of multi-channel sensing information, but also demonstrates the integrity and efficiency of the entire system, from signal multiplexing and transmission to final demodulation, ultimately improving the overall performance and practical value of the multi-parameter interferometric fiber optic sensing system.

[0153] An embodiment of the present application further provides an electronic device, including:

[0154] at least one memory;

[0155] at least one processor;

[0156] at least one program;

[0157] The program is stored in the memory, and the processor executes the at least one program to implement the data processing method of the multi-parameter interferometric fiber optic sensing system implemented in the present application. The electronic device can be any intelligent terminal including a mobile phone, a tablet computer, a personal digital assistant (PDA), an in-vehicle computer, etc.

[0158] See also Figure 11 , Figure 11 The hardware structure of an electronic device according to another embodiment is shown. The electronic device includes:

[0159] The processor 1101 can be implemented as a general-purpose CPU (Central Processing Unit), a microprocessor, an application-specific integrated circuit (ASIC), or one or more integrated circuits, and is used to execute relevant programs to implement the technical solutions provided in the embodiments of the present application;

[0160] The memory 1102 can be implemented in the form of ROM (Read Only Memory), static storage device, dynamic storage device, or RAM (Random Access Memory). The memory 1102 can store an operating system and other application programs. When the technical solutions provided in the embodiments of this specification are implemented through software or firmware, the relevant program code is stored in the memory 1102 and is called by the processor 1101 to execute the data processing method of the multi-parameter interferometric fiber optic sensing system of the embodiments of this application;

[0161] Input / output interface 1103, used to implement information input and output;

[0162] Communication interface 1104, used to implement communication interaction between this device and other devices, which can be achieved through wired means (such as USB, network cable, etc.) or wireless means (such as mobile network, WiFi, Bluetooth, etc.);

[0163] Bus 1105 , which transmits information between various components of the device (e.g., processor 1101 , memory 1102 , input / output interface 1103 , and communication interface 1104 );

[0164] The processor 1101 , the memory 1102 , the input / output interface 1103 and the communication interface 1104 are connected to each other in communication within the device via a bus 1105 .

[0165] An embodiment of the present application further provides a storage medium, which is a computer-readable storage medium and stores a computer program. When the computer program is executed by a processor, the data processing method of the multi-parameter interferometric optical fiber sensing system is implemented.

[0166] The memory, as a non-transient computer-readable storage medium, can be used to store non-transient software programs and non-transient computer executable programs. In addition, the memory may include a high-speed random access memory and may also include a non-transient memory, such as at least one disk storage device, a flash memory device, or other non-transient solid-state storage device. In some embodiments, the memory may optionally include a memory remotely arranged relative to the processor, and these remote memories may be connected to the processor via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0167] The embodiments described in the embodiments of this application are intended to more clearly illustrate the technical solutions of the embodiments of this application and do not constitute a limitation on the technical solutions provided by the embodiments of this application. Those skilled in the art will appreciate that with the evolution of technology and the emergence of new application scenarios, the technical solutions provided in the embodiments of this application are also applicable to similar technical problems.

[0168] Those skilled in the art will understand that the technical solutions shown in the figures do not constitute a limitation on the embodiments of the present application, and may include more or fewer steps than shown in the figures, or a combination of certain steps, or different steps.

[0169] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, i.e., they may be located in one place or distributed across multiple network units. Some or all of the modules may be selected based on actual needs to achieve the objectives of this embodiment.

[0170] Those skilled in the art will appreciate that all or some of the steps in the methods, systems, and functional modules / units in the devices disclosed above may be implemented as software, firmware, hardware, or appropriate combinations thereof.

[0171] The terms "first", "second", "third", "fourth", etc. (if any) in the specification 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 interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes 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.

[0172] It should be understood that in this application, "at least one (item)" means one or more, and "plurality" means two or more. "And / or" is used to describe the association relationship of associated objects, indicating that three relationships may exist. For example, "A and / or B" can mean: only A exists, only B exists, and A and B exist at the same time, where A and B can be singular or plural. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship. "At least one of the following items" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, at least one of a, b or c can mean: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, c can be single or multiple.

[0173] In the several embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of the above-mentioned units is only a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. The mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0174] The units described above as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0175] In addition, the functional units in the various embodiments of the present application may be integrated into a single processing unit, or each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0176] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product, which is stored in a storage medium and includes multiple instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of various embodiments of the present application. The aforementioned storage medium includes: various media that can store programs, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0177] The preferred embodiments of the present invention are described above with reference to the accompanying drawings, but are not intended to limit the scope of the present invention. Any modifications, equivalent substitutions, and improvements made by those skilled in the art without departing from the scope and essence of the present invention should be within the scope of the present invention.

Claims

1. A data processing method for a multi-parameter interferometric optical fiber sensing system, characterized in that: The multi-parameter interferometric optical fiber sensing system includes a plurality of interferometric optical fiber sensors, a receiving wavelength division multiplexer, a synthesizing wavelength division multiplexer, and a spectrometer. The method includes: Obtaining an interference spectrum of the interferometric fiber optic sensor, and determining an operating band of each interferometric fiber optic sensor based on the interference spectrum, wherein the operating bands of every two interferometric fiber optic sensors do not overlap; The target light source is divided by the receiving wavelength division multiplexer, and in each of the interferometric optical fiber sensors, the corresponding working band is used to respond to the divided target light source to obtain physical parameter signals, wherein the physical parameter signals are different from each other; Inputting all the physical parameter signals into the synthesizing wavelength division multiplexer for synthesis processing to obtain a composite optical signal; The composite light signal is input into a spectrometer for analysis and processing to obtain a multi-parameter analysis result of the target light source.

2. The data processing method of the multi-parameter interferometric optical fiber sensing system according to claim 1, characterized in that: The obtaining of the interference spectrum of the interferometric optical fiber sensor and determining the operating band of each interferometric optical fiber sensor based on the interference spectrum includes: Performing spectral measurement on the interferometric optical fiber sensor in an atmospheric environment to obtain an interference spectrum, wherein the interference spectrum includes beam phases of multiple light beams; Determining a plurality of non-overlapping interference sub-bands in the interference spectrum based on a phase difference between each two of the light beams; A different interference sub-band is selected for each of the interferometric optical fiber sensors as the working band of the interferometric optical fiber sensor.

3. The data processing method of the multi-parameter interferometric optical fiber sensing system according to claim 2, characterized in that: The step of determining a plurality of non-overlapping interference sub-bands in the interference spectrum based on the phase difference between each two of the light beams comprises: Taking each two phases of the light beams as test phases one by one, and when the phase difference between the test phases is a preset angle, taking the wavelength values corresponding to the two phases of the light beams corresponding to the test phases as a trough wavelength pair; Candidate wavelength pairs are obtained based on all the trough wavelength pairs, and the trough wavelength pairs that do not overlap with each other are selected from all the candidate wavelength pairs to obtain the interferometer band.

4. The data processing method of the multi-parameter interferometric optical fiber sensing system according to claim 1, characterized in that: The method of dividing the target light source by using the receiving wavelength division multiplexer and responding to the divided target light source by using the corresponding working band in each interferometric optical fiber sensor to obtain a physical parameter signal includes: For each of the interferometric fiber optic sensors, using the corresponding working band, select a wavelength division multiplexing sub-channel having a central wavelength matching the working band from the multiple wavelength division multiplexing sub-channels of the receiving wavelength division multiplexer as a matching sub-channel of the interferometric fiber optic sensor, and connect the interferometric fiber optic sensor to the corresponding matching sub-channel; After each matching sub-channel in the receiving wavelength division multiplexer receives the target light source, the target light source is divided using the corresponding working band to obtain a changing sub-light beam corresponding to each matching sub-channel, and the changing sub-light beam is transmitted to the corresponding interferometric optical fiber sensor; In each of the interferometric optical fiber sensors, the corresponding operating wavelength band is used to respond to the changing sub-beam to obtain the physical parameter signal.

5. The data processing method of the multi-parameter interferometric optical fiber sensing system according to claim 4, characterized in that: The working band includes a peak wavelength and a band bandwidth. For each of the interferometric optical fiber sensors, using the corresponding working band, selecting a wavelength division multiplexing sub-channel having a center wavelength matching the working band from multiple wavelength division multiplexing sub-channels of the receiving wavelength division multiplexer as a matching sub-channel of the interferometric optical fiber sensor, including: Using each of the interferometric optical fiber sensors as a matching sensor one by one; A wavelength division multiplexing sub-channel whose difference between a center wavelength and the peak wavelength is less than a preset tolerance value and whose channel bandwidth is greater than the band bandwidth is selected from the plurality of wavelength division multiplexing sub-channels as the matching sub-channel corresponding to the matching sensor.

6. The data processing method of the multi-parameter interferometric optical fiber sensing system according to claim 5, characterized in that: The step of inputting the composite light signal into a spectrometer for analysis and processing to obtain a multi-parameter analysis result of the target light source includes: In the spectrometer, each working band in the composite optical signal is analyzed respectively to obtain a variation of interference fringes; The optical path difference variation of the physical parameter corresponding to the working band is obtained based on the product of the interference fringe variation and the optical fiber refractive index of the matching sub-channel corresponding to the working band, and then divided by the peak wavelength of the working band; Obtaining parameter analysis results corresponding to physical parameters corresponding to the working band based on the optical path difference variation; Based on the parameter analysis results corresponding to all the physical parameters, the multi-parameter analysis result of the target light source is obtained.

7. The data processing method of the multi-parameter interferometric optical fiber sensing system according to claim 1, characterized in that: The step of inputting all the physical parameter signals into the synthesizing wavelength division multiplexer for synthesizing and processing to obtain a composite optical signal comprises: In the synthesized wavelength division multiplexer, index processing is performed based on the product of the fiber attenuation coefficient and the fiber transmission length of each physical parameter signal to obtain the fiber index parameter corresponding to each physical parameter signal; The product of the optical fiber index parameter and the light intensity of each of the physical parameter signals is accumulated to obtain the composite optical signal.

8. A multi-parameter interferometric optical fiber sensing system, characterized in that: include: Multiple interferometric fiber optic sensors, a synthesizing wavelength division multiplexer, a receiving wavelength division multiplexer, a spectrometer, and a control processor; The receiving wavelength division multiplexer is used to receive the target light source and obtain a plurality of changing sub-light beams after dividing; The interferometric optical fiber sensor is used to receive the corresponding changing sub-beam and respond using the corresponding working band to obtain a physical parameter signal; The synthesizing wavelength division multiplexer is used to synthesize the multiple physical parameter signals to obtain a composite optical signal; The spectrometer is used to analyze and process the composite light signal to obtain a multi-parameter analysis result of the target light source; The control processor is used to execute the data processing method of the multi-parameter interferometric optical fiber sensing system according to claim 1.

9. An electronic device, characterized in that: It comprises a memory and a processor, the memory stores a computer program, and is characterized in that when the processor executes the computer program, it implements the data processing method of the multi-parameter interferometric optical fiber sensing system according to any one of claims 1 to 7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the data processing method of the multi-parameter interferometric optical fiber sensing system according to any one of claims 1 to 7 is implemented.

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