An optical fiber distributed acoustic wave monitoring system

Abstract

The invention provides an optical fiber distributed acoustic wave monitoring system, and relates to the technical field of data processing. The system comprises: a signal transmission module; an optical signal transmitting module; an optical signal receiving module, which is used for receiving an optical signal after being transmitted through an optical fiber, and generating original waveform data according to a phase change and an intensity change of the optical signal; a noise reduction module, which is used for preprocessing the original waveform data to reduce an interference signal generated by environmental noise, and obtaining waveform analysis data; a signal demodulation module, which is used for demodulating the waveform analysis data according to a phase change and an intensity change, and extracting a characteristic signal caused by an external acoustic wave; and a data processing module, which is used for performing data analysis on the characteristic signal, generating sound source positioning information with a spatial position mark, and converting the sound source positioning information into visual data. The invention improves the accuracy of acoustic wave monitoring in a complex environment.

Description

Technical Field

[0001] The invention relates to the technical field of data processing, and in particular to an optical fiber distributed acoustic wave monitoring system. Background Art

[0002] In the existing technology of fiber-optic distributed acoustic wave monitoring system, the system usually uses optical fiber as the sensing medium, and uses the phase change and intensity change caused by the propagation of sound waves in the optical fiber to detect the acoustic changes in the surrounding environment. Such systems are widely used in the fields of oil and gas pipeline monitoring, border security and building structure health detection. Its basic working principle is to introduce optical signals into the optical fiber. When external sound waves interfere, the phase or intensity of the optical signal will change. The receiving end can obtain information such as the frequency, amplitude and position of the external sound waves through signal demodulation and processing technology, thereby realizing continuous and real-time distributed acoustic wave monitoring.

[0003] However, existing fiber-optic distributed acoustic wave monitoring systems have certain limitations in the process of accurately locating sound sources. Because the system relies on phase change demodulation technology, when multiple sound sources act on different positions of the optical fiber at the same time, the phase change signals generated by different sound sources may interfere with each other, resulting in signal overlap and confusion, which increases the difficulty of analysis and positioning. In long-distance fiber-optic monitoring scenarios, such as leak monitoring of oil and gas pipelines, the phenomenon of interference from multiple sound sources is particularly significant. This technical defect will lead to a decrease in the accuracy of signal recognition and separation in complex noise environments, affecting the real-time and accurate positioning of the sound source. Summary of the invention

[0004] The purpose of the present invention is to provide an optical fiber distributed acoustic wave monitoring system, aiming to solve the problems mentioned in the background technology.

[0005] In order to solve the above technical problems, the technical solution of the present invention is as follows:

[0006] An optical fiber distributed acoustic wave monitoring system, the system comprising:

[0007] A signal transmission module, including an optical fiber laid along a preset path, for transmitting phase or intensity change data caused by sound waves under the action of external sound waves;

[0008] An optical signal transmitting module, used to inject an optical signal with a preset frequency and power into the optical fiber;

[0009] An optical signal receiving module is used to receive the optical signal after being transmitted through the optical fiber, and generate original waveform data according to the phase change and intensity change of the optical signal;

[0010] The noise reduction module is used to pre-process the original waveform data through an adaptive filter and dynamically adjust the bandwidth when the noise environment changes drastically to obtain waveform analysis data;

[0011] The signal demodulation module is used to demodulate the waveform analysis data according to the phase change and intensity change, and extract the characteristic signal caused by the external sound wave;

[0012] The data processing module is used to slice the characteristic signal according to the monitoring area, so that each slice data is processed in parallel in multiple processing units, generate sound source localization information with spatial position marks, and convert it into visual data.

[0013] Preferably, the signal transmission module includes:

[0014] An optical fiber protection sleeve, covering the surface of the optical fiber, comprises an inner shock-resistant material layer and an outer wear-resistant material layer, wherein the inner shock-resistant material layer is a flexible structure, and the outer wear-resistant material layer is a hard coating;

[0015] Environmental adaptation layer, attached to the outside of the optical fiber protection sleeve.

[0016] Preferably, the optical signal transmitting module comprises:

[0017] A laser light source, used for emitting a laser signal with an adjustable wavelength;

[0018] Optical intensity regulator, used to dynamically adjust the power of the optical signal according to the monitoring distance;

[0019] The optical intensity regulator dynamically adjusts the power of the optical signal by the following formula:

[0020] ,

[0021] in, is the laser power after dynamic adjustment, is the initial laser power, is the distance attenuation coefficient, is the frequency loss coefficient, is the frequency, is the transmission distance of the optical signal in the optical fiber, is the frequency loss index, is the feedback coefficient, and represent the reference signal strength and the received signal strength respectively, is the adjustment coefficient.

[0022] Preferably, the optical signal receiving module comprises a multi-layer filter array for performing multi-band separation filtering on the received optical signal;

[0023] The multi-layer filter array includes a low-pass filter, a high-pass filter and a band-pass filter, wherein the low-pass filter is used to remove high-frequency interference signals, the high-pass filter is used to suppress low-frequency environmental noise, and the band-pass filter is used to retain effective signals in the target frequency band.

[0024] Preferably, the noise reduction module comprises:

[0025] A noise feature recognition unit is used to analyze the noise characteristics in the original waveform data, identify the high-frequency and low-frequency noise components, and mark the noise frequency range according to the noise feature library to generate noise marking data;

[0026] An adaptive filtering unit is used to dynamically adjust the filtering parameters according to the noise marker data, and adaptively filter the original waveform data to obtain waveform analysis data;

[0027] The bandwidth dynamic adjustment unit is used to adjust the bandwidth of the adaptive filter unit when the noise environment changes drastically to obtain the dynamic bandwidth. The dynamic bandwidth is adjusted by the following formula:

[0028] ,

[0029] in, is the dynamic bandwidth, is the initial bandwidth, is the signal-to-noise ratio, To adjust the parameters, is the noise threshold, is the adjustment coefficient, and are the ambient noise intensity and the effective noise intensity, is the adjustment factor.

[0030] Preferably, the signal demodulation module comprises:

[0031] The phase demodulation unit is used to extract the phase change information of each sound source from the waveform analysis data and generate phase demodulation data with phase characteristics. The phase demodulation data is realized by the following formula:

[0032] ,

[0033] in, is the phase demodulated signal, For the The amplitude of a sound source, For the The frequency of the sound source, is the time variable, For the The initial phase of the sound source, For the The time attenuation coefficient of a sound source is , For the The sound source at time The signal strength at For the The sound source is The signal strength at is the frequency domain signal, is the total number of sound sources;

[0034] The intensity demodulation unit is used to extract the intensity characteristics of each sound source from the waveform analysis data and generate intensity demodulation data with intensity characteristics. The intensity demodulation data is realized by the following formula:

[0035] ,

[0036] in, is the intensity signal after separation, For the The initial strength of the sound source, For the The intensity attenuation coefficient of a sound source, , For the The sound source is at a distance The signal strength at For the The sound source is Signal strength at ;

[0037] A signal vectorization unit, used for synchronizing the phase demodulation data and the intensity demodulation data in time, and combining the phase characteristics and intensity characteristics of each sound source in time into a characteristic vector;

[0038] The characteristic signal generating unit is used to summarize the characteristic vectors of different sound sources to form a characteristic matrix and output it as a characteristic signal.

[0039] Preferably, the data processing module includes:

[0040] A positioning data generating unit, used to divide the characteristic signals according to the monitoring area and convert the characteristic signals into preliminary positioning data with spatial position marks;

[0041] A regional data integration unit is used to integrate the preliminary positioning data of different monitoring areas by analyzing the relative position and intensity changes of the sound source signals in each area to generate regional integrated positioning data;

[0042] A sound source localization unit, used to integrate the localization data according to the region and determine the sound source localization information of each sound source;

[0043] The visual positioning generation unit is used to convert the sound source positioning information into visual data with spatial coordinates and time tags.

[0044] Preferably, the positioning data generating unit comprises:

[0045] A signal partition processing unit, used to divide the characteristic signal into a number of signal partitions according to the monitoring area, each signal partition containing characteristic data in the area;

[0046] A spatial position calibration unit is used to calibrate the position of each signal partition data and add a spatial position mark to each signal partition according to a preset area division strategy;

[0047] The preliminary positioning data generating unit is used to merge the signal partition data with spatial position marks into a set to generate preliminary positioning data for each monitoring area.

[0048] Preferably, the regional data integration unit comprises:

[0049] A regional feature extraction unit is used to extract the intensity, phase and position characteristics of the sound source signal in each monitoring area according to the preliminary positioning data, and generate a feature data set with regional characteristics;

[0050] The cross-region matching unit is used to compare and match the sound source features in different monitoring areas between adjacent areas according to the feature data set, associate the cross-region data belonging to the same sound source, and generate a matching data set;

[0051] A consistency checking unit, used for calculating the time decay rate of each region and screening the matching data set according to the difference of the time decay rate to obtain a consistency calibration data set;

[0052] The regional integration generation unit is used to merge the sound source data of adjacent regions into a set according to the consistent calibration data set, so as to obtain regional integration data, which includes the preliminary position and regional mark of each sound source.

[0053] Preferably, the sound source localization unit comprises:

[0054] A position determination unit, used for obtaining a precise positioning data set by performing precise position calculation on the multi-dimensional features of the sound source according to the fine comparison data set;

[0055] The high-precision output generation unit is used to generate sound source localization information based on the precise positioning data set, and the sound source localization information includes time and space coordinate information.

[0056] The above solution of the present invention includes at least the following beneficial effects:

[0057] The fiber-optic distributed acoustic wave monitoring system of the present invention can realize efficient and accurate sound source monitoring and positioning in a variable noise environment through the collaborative work of multiple modules. Compared with traditional acoustic wave monitoring systems, the present invention has significant advantages in signal conduction, noise suppression, data demodulation and distributed data processing, and is suitable for complex environmental monitoring scenarios.

[0058] First, the signal transmission module effectively transmits the phase and intensity changes caused by external sound waves to the receiving end through the optical fiber laid on the preset path, realizing the stable transmission of long-distance sound wave signals. Compared with traditional cables or wireless transmission, the optical fiber transmission of the present invention is not affected by electromagnetic interference and is suitable for scenes with complex electromagnetic environments, such as underground pipe networks or industrial facilities. In addition, the optical fiber signal can maintain a low attenuation rate during long-distance transmission, ensuring the accuracy of the transmitted data, laying a good foundation for subsequent analysis.

[0059] The optical signal transmitting and receiving module can effectively realize the injection and collection of signals. By injecting the optical signal of preset frequency and power into the optical fiber through the transmitting module, the system can maintain stable signal characteristics on the transmission path. The optical signal receiving module can generate original waveform data through phase and intensity changes to ensure sensitivity to changes in the sound source. In traditional monitoring systems, signal transmission often causes data distortion due to path instability and signal attenuation. The optical signal transmitting and receiving module of the present invention cooperates with optical fiber transmission to achieve high-quality data transmission and ensure the integrity of the original waveform data.

[0060] The noise reduction module pre-processes the original waveform data through an adaptive filter, which can automatically adjust the filter parameters according to the noise characteristics and realize dynamic adjustment of the bandwidth when the noise environment changes drastically. Compared with traditional filters with fixed bandwidth, adaptive filters can effectively cope with complex noise environments and ensure that clear signal data can still be extracted in strong interference scenarios. The dynamic bandwidth adjustment function of this module enables the system to maintain a high signal-to-noise ratio output when facing sudden noise changes, improves the accuracy of monitoring and the anti-interference ability of the system, and is suitable for fine monitoring needs in urban noise complex areas or industrial environments.

[0061] The signal demodulation module demodulates the waveform analysis data after noise reduction, and can extract the characteristic signal of the sound source according to the phase and intensity changes. Through the dual demodulation of phase and intensity, the system can obtain the frequency, phase and intensity information of multiple sound sources respectively, and realize signal separation in a multi-sound source environment. Compared with the traditional single demodulation method, the dual demodulation method of the present invention can effectively distinguish the overlapping sound source signals, provide accurate basic data for subsequent positioning, and is suitable for monitoring applications in complex scenes with multiple sound sources.

[0062] The data processing module uses a distributed processing method to process the characteristic signals in slices according to the monitoring area, so that the data of each slice can be analyzed in parallel in multiple processing units. Compared with the traditional centralized processing method, this distributed data processing method greatly improves the efficiency of data processing and the scalability of the system. In large-scale monitoring scenarios, distributed processing can effectively process large amounts of real-time data and quickly generate sound source positioning information with spatial position markers. Through visual data output, the system can display the distribution and position changes of the sound source in real time on the monitoring interface, which is convenient for managers to provide timely warnings and interventions in the monitoring area.

[0063] In summary, the optical fiber distributed acoustic wave monitoring system of the present invention overcomes the shortcomings of traditional systems in long-distance signal transmission, anti-interference ability, signal demodulation accuracy and data processing efficiency through modular design and distributed processing, and is suitable for large-scale sound source monitoring and precise positioning in complex environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0064] Figure 1 It is an architecture diagram of an optical fiber distributed acoustic wave monitoring system provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0065] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0066] like Figure 1 As shown, an embodiment of the present invention provides an optical fiber distributed acoustic wave monitoring system, the system comprising:

[0067] A signal transmission module, including an optical fiber laid along a preset path, for transmitting phase or intensity change data caused by sound waves under the action of external sound waves;

[0068] An optical signal transmitting module, used to inject an optical signal with a preset frequency and power into the optical fiber;

[0069] An optical signal receiving module is used to receive the optical signal after being transmitted through the optical fiber, and generate original waveform data according to the phase change and intensity change of the optical signal;

[0070] The noise reduction module is used to pre-process the original waveform data through an adaptive filter and dynamically adjust the bandwidth when the noise environment changes drastically to obtain waveform analysis data;

[0071] The signal demodulation module is used to demodulate the waveform analysis data according to the phase change and intensity change, and extract the characteristic signal caused by the external sound wave;

[0072] The data processing module is used to slice the characteristic signal according to the monitoring area, so that each slice data is processed in parallel in multiple processing units, generate sound source localization information with spatial position marks, and convert it into visual data.

[0073] In the embodiment of the present invention, through the synergy of multiple modules, real-time monitoring and precise positioning in a multi-sound source environment are achieved, with high reliability and adaptability. The system first uses the signal transmission module to use the optical fiber laid along the preset path as the signal transmission medium, which can stably transmit the phase and intensity change data generated by the external sound waves over a long distance. Compared with traditional cable transmission, optical fiber not only has the advantage of anti-electromagnetic interference, but also can maintain the stability of data transmission in a complex monitoring environment, ensuring the system's accurate signal acquisition in long-distance and multi-interference environments.

[0074] The optical signal transmitting module injects an optical signal with a preset frequency and power into the optical fiber. By precisely controlling the frequency and power of the transmitted signal, the system can sensitively perceive subtle changes in external sound waves. The optical signal receiving module receives the optical signal transmitted through the optical fiber, and captures the phase change and intensity change of the optical signal in real time to generate high-fidelity original waveform data. This two-way signal control and reception mechanism enables the system to maintain high signal transmission accuracy and response speed in long-distance monitoring scenarios, providing accurate input data for subsequent noise reduction and data processing.

[0075] The noise reduction module uses an adaptive filter to pre-process the original waveform data and dynamically adjusts the bandwidth when the noise environment changes dramatically to ensure a high signal-to-noise ratio output of the signal. Compared with fixed bandwidth filters, this module can adjust the filter parameters in real time to adapt to different noise interference situations, so that the system can still effectively remove interference signals in complex noise environments and obtain clear waveform analysis data, thereby improving the system's adaptability and anti-interference ability in a changing environment.

[0076] The signal demodulation module demodulates the waveform analysis data after noise reduction processing, and can extract the characteristic signal of the sound source based on phase and intensity changes. This dual demodulation method effectively improves the accuracy of multi-source separation, can identify and distinguish the information of different sound sources in the same monitoring area, and ensures that the frequency, phase and intensity data extracted in the multi-source scenario are clear and reliable, laying a data foundation for subsequent positioning analysis.

[0077] The data processing module further processes the characteristic signals in slices according to the monitoring area, so that each slice of data can be processed in parallel in multiple processing units, thereby improving the data processing efficiency of the system. The distributed data processing method not only makes the system more efficient in large-scale monitoring scenarios, but also provides data support for the real-time generation of sound source positioning information with spatial position markers. By converting positioning information into visual data, the system can intuitively display the distribution and position changes of the sound source on the monitoring interface, allowing operators to obtain the location of the sound source in the monitoring area in a timely and accurate manner, providing support for the monitoring and emergency decision-making of emergencies.

[0078] In a preferred embodiment of the present invention, the signal transmission module includes:

[0079] An optical fiber protection sleeve, covering the surface of the optical fiber, comprises an inner shock-resistant material layer and an outer wear-resistant material layer, wherein the inner shock-resistant material layer is a flexible structure, and the outer wear-resistant material layer is a hard coating;

[0080] Environmental adaptation layer, attached to the outside of the optical fiber protection sleeve.

[0081] In the embodiment of the present invention, the design of the signal transmission module plays a key supporting role in the system. The module adopts a shock-resistant and wear-resistant protective sleeve structure. The inner layer is a flexible shock-resistant material that effectively absorbs external vibrations, and the outer layer uses wear-resistant materials to protect the optical fiber from damage in complex environments. In addition, an environmental adaptation layer is added to the outside of the optical fiber, which can adapt to various environments such as underwater, humid, and high temperature, providing stable support for optical fiber signal transmission.

[0082] Unlike traditional bare optical fibers or ordinary protective sleeves, this module can maintain the integrity of the optical fiber and the stability of signal transmission in extreme environments. For example, in earthquake monitoring or submarine pipeline inspection, traditional optical fibers are easily damaged and cause signal distortion, while the anti-seismic and wear-resistant structure of the present invention significantly improves the durability and environmental adaptability of the optical fiber, thereby ensuring the stability of the system under harsh conditions and the accuracy of data transmission.

[0083] Specifically, the inner seismic material layer is used to absorb and buffer external vibration interference, ensuring that the optical fiber remains stable when subjected to external physical impact. Usually, flexible materials such as silicone rubber or polyurethane foam are used. Such materials have good seismic and vibration reduction properties, and can effectively absorb the impact from earthquakes, mechanical vibrations or ground construction, protecting the integrity of the optical fiber.

[0084] The main function of the outer wear-resistant material layer is to prevent the optical fiber from being worn or corroded in harsh environments. It is suitable to use hard polymer materials or metal coatings, such as high-density polyethylene or stainless steel materials, which have good wear resistance, corrosion resistance and extrusion resistance. This layer of protection can ensure that the optical fiber is not easily worn in complex terrain or underground environments, and extend the life of the optical fiber.

[0085] The environmental adaptation layer further enhances the adaptability of the optical fiber, especially the stability of signal transmission in underwater, desert or humid environments. This layer can be made of special polymer materials that are waterproof, high temperature resistant and low temperature resistant, such as polytetrafluoroethylene or fluorinated rubber. These materials have excellent chemical corrosion resistance and can effectively adapt to temperature and humidity changes in extreme environments, ensuring high-quality transmission of optical fiber signals.

[0086] In a preferred embodiment of the present invention, the optical signal transmission module includes:

[0087] A laser light source, used for emitting a laser signal with an adjustable wavelength;

[0088] Optical intensity regulator, used to dynamically adjust the power of the optical signal according to the monitoring distance;

[0089] The optical intensity regulator dynamically adjusts the power of the optical signal by the following formula:

[0090] ,

[0091] in, is the laser power after dynamic adjustment, is the initial laser power, the reference power set by the optical signal transmitting module, is the distance attenuation coefficient, which is calculated based on the known attenuation characteristics of the optical fiber material and the standard transmission distance. The attenuation coefficient of a typical optical fiber material is usually 0.2 dB / km. is the frequency loss coefficient, which is calculated according to the loss law of signal frequency and depends on the characteristics of signal frequency and transmission medium. is the frequency, is the transmission distance of the optical signal in the optical fiber, is the frequency loss index, which is used to correct the nonlinear characteristics of frequency loss and is usually set to 1.5. is the feedback coefficient, which is set according to the system control stability and is usually in the range of 0.5 to 1.5. and represent the reference signal strength and the received signal strength respectively, The target signal strength set for the system is set to the ideal receiving signal value under standard working conditions. It is an adjustment coefficient, which is set according to the adaptation requirements of environmental changes.

[0092] In single-mode optical fiber, Typically between 0.2 and 0.35 dB / km;

[0093] In multimode optical fiber, Typically between 0.5 and 1.0 dB / km.

[0094] In the embodiment of the present invention, the optical signal transmission module realizes dynamic control of the optical signal transmission power through the cooperation of the laser light source and the optical intensity regulator. The laser signal emitted by the light source has an adjustable wavelength and can be flexibly adjusted according to the different needs of the monitoring area. The optical intensity regulator dynamically adjusts the power of the optical signal according to the distance and the attenuation of the signal transmission, so that the optical signal can maintain a stable intensity during long-distance transmission, avoiding the limitations of traditional fixed power transmission.

[0095] Through the adjustment mechanism of the feedback formula, the optical intensity regulator of the present invention can adjust the transmission power in real time according to the received signal feedback, ensuring the stability of signal strength in long-distance transmission. For example, in large-scale oil and gas pipeline monitoring, different distances and angles will cause signal attenuation, and traditional fixed power is difficult to adapt. However, this module maintains signal consistency through real-time power adjustment, greatly improving the monitoring coverage and data effectiveness.

[0096] Specifically, the signal strength in the present invention is represented by power.

[0097] In a preferred embodiment of the present invention, the optical signal receiving module includes a multi-layer filter array for performing multi-band separation filtering on the received optical signal;

[0098] The multi-layer filter array includes a low-pass filter, a high-pass filter and a band-pass filter, wherein the low-pass filter is used to remove high-frequency interference signals, the high-pass filter is used to suppress low-frequency environmental noise, and the band-pass filter is used to retain effective signals in the target frequency band.

[0099] In the embodiment of the present invention, the optical signal receiving module realizes the frequency band separation of the received signal and the automatic shielding of the background noise through the multi-layer filter array. The low-pass, high-pass and band-pass filters in the multi-layer filter process the noise in the high-frequency, low-frequency and intermediate frequency bands respectively to ensure the extraction of effective signals.

[0100] Compared with traditional simple filters, this module has multi-level noise filtering capabilities and can effectively adapt to multi-band signal transmission in complex environments. For example, in urban pipe networks, there are various noise interferences in the surrounding environment. This module can filter out valuable signal frequency bands and is suitable for accurate monitoring in high-noise scenarios.

[0101] In a preferred embodiment of the present invention, the noise reduction module includes:

[0102] A noise feature recognition unit is used to analyze the noise characteristics in the original waveform data, identify the high-frequency and low-frequency noise components, and mark the noise frequency range according to the noise feature library to generate noise marking data;

[0103] An adaptive filtering unit is used to dynamically adjust the filtering parameters according to the noise marker data, and adaptively filter the original waveform data to obtain waveform analysis data;

[0104] The bandwidth dynamic adjustment unit is used to adjust the bandwidth of the adaptive filter unit when the noise environment changes drastically to obtain the dynamic bandwidth. The dynamic bandwidth is adjusted by the following formula:

[0105] ,

[0106] in, is the dynamic bandwidth, is the initial bandwidth, is the signal-to-noise ratio, To adjust the parameters, is the noise threshold, is the adjustment coefficient, and are the ambient noise intensity and the effective noise intensity, is the adjustment factor.

[0107] In an embodiment of the present invention, the noise reduction module realizes efficient noise reduction through noise feature recognition, adaptive filtering and dynamic bandwidth adjustment. The noise feature recognition unit analyzes the noise components in the original waveform data and marks them as high-frequency or low-frequency noise, providing a basis for subsequent filtering processing. The adaptive filtering unit dynamically adjusts the filtering parameters according to the noise marking data, thereby achieving adaptive noise reduction effects in different noise environments. The bandwidth dynamic adjustment unit automatically adjusts the bandwidth of the filter according to the fluctuation of the environmental noise, ensuring that the system efficiently handles complex noise environments.

[0108] Compared with traditional static filtering technology, this module can respond to changes in environmental noise in real time and achieve more accurate noise suppression. For example, in railway monitoring, due to the interference of train and external environmental noise, conventional filters are difficult to maintain signal clarity. This module dynamically adjusts the bandwidth and adaptively optimizes under different noise conditions, significantly improving signal quality.

[0109] Specifically, the noise feature recognition unit is used to analyze and extract noise characteristics of different frequencies from the original waveform data. Its working principle is based on signal processing algorithms, such as fast Fourier transform to decompose the original signal into components of each frequency band and identify the noise frequency characteristics therein. The identified noise characteristics will be compared with the noise feature library preset by the system to mark the noise in a specific frequency band as high-frequency noise or low-frequency noise, and generate noise labeling data. The main advantage of this unit is that it can provide accurate frequency band references for subsequent filtering operations, realizing differentiated processing for different noise sources.

[0110] The adaptive filtering unit adapts to the changes of different noise environments by dynamically adjusting the filtering parameters. The adaptive filtering unit adjusts the parameters such as the bandwidth, gain and filter order of the filter in real time according to the noise marker data generated by the noise feature recognition unit. This adaptability can be achieved through the recursive least squares algorithm or the Kalman filter algorithm, so as to optimize the filtering effect according to the real-time noise conditions. Compared with the traditional static filter, the adaptive filtering unit can effectively cope with the dynamic changes of the noise spectrum and ensure that the signal maintains a high signal-to-noise ratio in a complex environment.

[0111] In a preferred embodiment of the present invention, the signal demodulation module includes:

[0112] The phase demodulation unit is used to extract the phase change information of each sound source from the waveform analysis data and generate phase demodulation data with phase characteristics. The phase demodulation data is realized by the following formula:

[0113] ,

[0114] in, is the phase demodulated signal, For the The amplitude of a sound source, For the The frequency of the sound source, is the time variable, For the The initial phase of the sound source, For the The time attenuation coefficient of a sound source is , For the The sound source at time The signal strength at For the The sound source is The signal strength at is the frequency domain signal, is the total number of sound sources;

[0115] The intensity demodulation unit is used to extract the intensity characteristics of each sound source from the waveform analysis data and generate intensity demodulation data with intensity characteristics. The intensity demodulation data is realized by the following formula:

[0116] ,

[0117] in, is the intensity signal after separation, For the The initial strength of the sound source, For the The intensity attenuation coefficient of a sound source, , For the The sound source is at a distance The signal strength at For the The sound source is Signal strength at ;

[0118] A signal vectorization unit, used for synchronizing the phase demodulation data and the intensity demodulation data in time, and combining the phase characteristics and intensity characteristics of each sound source in time into a characteristic vector;

[0119] The characteristic signal generating unit is used to summarize the characteristic vectors of different sound sources to form a characteristic matrix and output it as a characteristic signal.

[0120] In an embodiment of the present invention, the signal demodulation module includes a phase demodulation unit and an intensity demodulation unit, which respectively extract the phase and intensity characteristics of the sound source. The phase demodulation unit extracts the phase change information of each sound source from the waveform analysis data, while the intensity demodulation unit extracts the intensity characteristics of the sound source, and synchronizes the two to generate a feature vector, which ultimately constitutes a feature matrix output. This demodulation method ensures that the system can clearly separate the phase and intensity characteristics of multiple sound source signals, providing accurate feature data for subsequent data processing.

[0121] Different from the simple phase or intensity demodulation in the prior art, this module achieves more accurate signal separation and feature extraction through dual demodulation. For example, in an underground pipe network with multiple sound sources, the sound source signals of different pipes may overlap. This demodulation module can effectively separate the overlapping signals and provide more accurate multi-sound source monitoring data.

[0122] In a preferred embodiment of the present invention, the data processing module includes:

[0123] A positioning data generating unit, used to divide the characteristic signals according to the monitoring area and convert the characteristic signals into preliminary positioning data with spatial position marks;

[0124] A regional data integration unit is used to integrate the preliminary positioning data of different monitoring areas by analyzing the relative position and intensity changes of the sound source signals in each area to generate regional integrated positioning data;

[0125] A sound source localization unit, used to integrate the localization data according to the region and determine the sound source localization information of each sound source;

[0126] The visual positioning generation unit is used to convert the sound source positioning information into visual data with spatial coordinates and time tags.

[0127] In an embodiment of the present invention, the data processing module realizes accurate positioning and display of the sound source by performing regional positioning, integration, refined positioning and visualization processing on the characteristic signal. The positioning data generation unit converts the characteristic signal into preliminary positioning data according to the monitoring area, and the regional data integration unit integrates the data in different areas to provide cross-regional sound source location information. The sound source positioning unit realizes accurate calibration of the sound source by further refining the positioning. The visualization positioning generation unit finally generates visualization data with spatial coordinates and time tags, providing a clear real-time positioning display for the monitoring interface.

[0128] Compared with the existing single positioning technology, this module not only supports the integration of sound sources in multiple regions, but also has high-precision positioning and visualization functions. For example, in municipal pipeline leakage monitoring, traditional monitoring can only provide fuzzy locations, while the present invention can accurately mark the coordinates of the sound source on the map and update its location in real time, facilitating timely investigation and maintenance, and improving the accuracy and response speed of monitoring.

[0129] Specifically, the visualization positioning generation unit is used to convert the high-precision sound source positioning data generated by the system into visualization data with time and space tags to support real-time monitoring and location display. This unit includes the following three main steps:

[0130] Coordinate conversion: The spatial position and time information of the sound source are converted into a standard three-dimensional coordinate system for accurate presentation on the visual interface. This step usually uses the three-dimensional coordinate system of geographic information system (GIS) or computer-aided design (CAD) software for location marking.

[0131] Adding time stamps: Adding time stamps to the location data of each sound source ensures that the data can reflect the dynamic changes of the sound source when it is visualized. These time stamps can help users track the movement trajectory of the sound source and form a time-series change diagram of the sound source position.

[0132] Visual graphics generation: Generate a graphical display interface with time and space-tagged positioning data, and use heat maps, trajectory lines, or real-time point markings to display the distribution and changes of sound sources. This visualization process can reflect the location and status of the sound source in real time, which is suitable for the interface display of the monitoring platform, making it easy for operators to intuitively obtain the spatial location and historical trajectory of the sound source.

[0133] In a preferred embodiment of the present invention, the positioning data generating unit includes:

[0134] A signal partition processing unit, used to divide the characteristic signal into a number of signal partitions according to the monitoring area, each signal partition containing characteristic data in the area;

[0135] A spatial position calibration unit is used to calibrate the position of each signal partition data and add a spatial position mark to each signal partition according to a preset area division strategy;

[0136] The preliminary positioning data generating unit is used to merge the signal partition data with spatial position marks into a set to generate preliminary positioning data for each monitoring area.

[0137] In an embodiment of the present invention, the positioning data generation unit is responsible for partitioning and calibrating the position of the characteristic signal in the system to provide basic support for the preliminary positioning of multi-region sound sources. The signal partition processing unit first divides the characteristic signal into several signal partitions according to the monitoring area to ensure that each partition data is exclusive to its corresponding area. Next, the spatial position calibration unit calibrates the signal partitions and adds spatial position information to each signal partition according to the preset spatial division scheme. The preliminary positioning data generation unit further integrates these partition data and outputs preliminary positioning data with spatial position marks to provide a position reference for subsequent data processing.

[0138] The advantage of this unit is that it can accurately partition and calibrate the location of sound source signals in complex environments, thus avoiding the problem of signal overlap or regional confusion. For example, in multi-section leakage monitoring of municipal pipe networks, traditional methods often cause data confusion between different areas due to signal similarity. Through precise partitioning and calibration, this unit can effectively distinguish the data sources of each monitoring section, ensure the accuracy of subsequent positioning, and improve the accuracy of monitoring.

[0139] Specifically, the role of the spatial position calibration unit is to calibrate the signal partition data so that it has clear spatial coordinate information. The unit assigns a specific spatial position to each signal partition based on the preset area division strategy. For example, in an underground pipeline monitoring application, the length, depth, and direction coordinates of the pipeline can be assigned to each partition. During the calibration process, the reference point coordinates and laser ranging technology can be combined to ensure that each signal partition has a clear position mark to avoid interference across regions or signal overlap.

[0140] The preliminary positioning data generation unit is used to merge the signal partition data with spatial position marks into a set to generate preliminary positioning data for each monitoring area. The unit first receives the calibration data output by the spatial position calibration unit, and then integrates the signal partition data into overall regional positioning information based on the characteristics of the monitoring area. The preliminary positioning data generated by this process not only contains the signal characteristics of each partition, but also contains the spatial position information within the area, providing accurate basic data for subsequent regional data integration and high-precision positioning.

[0141] In a preferred embodiment of the present invention, the regional data integration unit includes:

[0142] A regional feature extraction unit is used to extract the intensity, phase and position characteristics of the sound source signal in each monitoring area according to the preliminary positioning data, and generate a feature data set with regional characteristics;

[0143] The cross-region matching unit is used to compare and match the sound source features in different monitoring areas between adjacent areas according to the feature data set, associate the cross-region data belonging to the same sound source, and generate a matching data set;

[0144] A consistency checking unit, used for calculating the time decay rate of each region and screening the matching data set according to the difference of the time decay rate to obtain a consistency calibration data set;

[0145] The regional integration generation unit is used to merge the sound source data of adjacent regions into a set according to the consistent calibration data set, so as to obtain regional integration data, which includes the preliminary position and regional mark of each sound source.

[0146] In an embodiment of the present invention, the regional data integration unit realizes the matching and consistency calibration of cross-regional sound source data through step-by-step processing, ensuring the accurate integration of sound source data in multi-region monitoring scenarios. First, the regional feature extraction unit can extract the intensity, phase and position characteristics of the sound source signal in each monitoring area, and mark these feature data as regional feature data sets. This processing step ensures the consistency of the sound source data in each area in format and structure, providing a basis for subsequent cross-region matching.

[0147] The cross-region matching unit compares and matches the sound source data of adjacent regions through the feature data set. This unit uses similar features of signals, such as frequency, phase, intensity, etc., to associate the same sound source data across regions, effectively eliminating data redundancy between multiple regions. Compared with traditional single-region data processing, the present invention realizes signal association identification and information integration between multiple regions, thereby enhancing the data consistency and reliability of the system in large-scale monitoring.

[0148] The consistency check unit further calibrates the matching data set output by the cross-region matching unit by calculating the difference in time decay rate. By comparing the time decay rate, the mismatched signals can be effectively eliminated to ensure that each set of cross-region sound source data has a high degree of consistency. Finally, the regional integration generation unit integrates the sound source data of adjacent regions into unified regional integration data based on the consistency calibration data set, providing a reliable data basis for subsequent precise positioning.

[0149] Compared with the existing technology, the present invention provides a multi-level data processing method from feature extraction to consistency verification, which enables the system to accurately identify and integrate cross-region sound source information in a complex environment with multiple regions and multiple sound sources, greatly improving the monitoring accuracy.

[0150] Specifically, the cross-region matching unit is used to compare and match the data of adjacent monitoring areas to ensure that the detection results of the same sound source in different areas are consistent. The unit first receives the feature data set generated by the regional feature extraction unit, analyzes the intensity, frequency and position similarity of the sound source signals in adjacent areas, and uses the feature similarity formula to associate and match the cross-region data belonging to the same sound source to generate a matching data set. Through cross-region matching, the repetition and redundancy of cross-region data can be effectively reduced, ensuring the accuracy of sound source positioning.

[0151] In a preferred embodiment of the present invention, the sound source localization unit includes:

[0152] A position determination unit, used for obtaining a precise positioning data set by performing precise position calculation on the multi-dimensional features of the sound source according to the fine comparison data set;

[0153] The high-precision output generation unit is used to generate sound source localization information based on the precise positioning data set, and the sound source localization information includes time and space coordinate information.

[0154] In an embodiment of the present invention, the sound source localization unit realizes accurate positioning and information output of the sound source through high-precision position calculation and positioning information generation. The position determination unit generates an accurate positioning data set by calculating the multi-dimensional features of the sound source in the regional integrated data, such as frequency, phase, intensity, etc. Compared with the ordinary single-dimensional positioning method, the multi-dimensional feature calculation method of the present invention can more comprehensively analyze the spatial position of the sound source, so that the positioning accuracy is significantly improved. This feature is particularly suitable for fine monitoring in complex environments, and can provide high-precision positioning results in the case of multi-signal interference.

[0155] The high-precision output generation unit converts the precise positioning data set into sound source positioning information containing time and space coordinates for subsequent visualization and real-time monitoring. The output sound source positioning information can be intuitively displayed on the monitoring interface, allowing operators to accurately grasp the distribution and dynamic changes of the sound source. This way of generating positioning information ensures the applicability of the system in high-precision monitoring, and can provide the spatial location of the sound source in real time and accurately, providing reliable data support for responding to emergencies and monitoring decisions.

[0156] Compared with existing positioning technologies, it has stronger adaptability in complex environments and higher positioning accuracy. Especially in large-scale monitoring scenarios, the system's high-precision output mechanism provides important technical support for rapid response and dynamic monitoring, significantly improving the practical value of the monitoring system.

[0157] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. An optical fiber distributed acoustic wave monitoring system, characterized in that: The system comprises: A signal transmission module, including an optical fiber laid along a preset path, for transmitting phase or intensity change data caused by sound waves under the action of external sound waves; An optical signal transmitting module, used to inject an optical signal with a preset frequency and power into the optical fiber; An optical signal receiving module is used to receive the optical signal after being transmitted through the optical fiber, and generate original waveform data according to the phase change and intensity change of the optical signal; The noise reduction module is used to pre-process the original waveform data through an adaptive filter and dynamically adjust the bandwidth when the noise environment changes drastically to obtain waveform analysis data; The signal demodulation module is used to demodulate the waveform analysis data according to the phase change and intensity change, and extract the characteristic signal caused by the external sound wave; The data processing module is used to slice the characteristic signal according to the monitoring area, so that each slice data is processed in parallel in multiple processing units, generate sound source localization information with spatial position marks, and convert it into visual data; The optical signal transmitting module comprises: A laser light source, used for emitting a laser signal with an adjustable wavelength; Optical intensity regulator, used to dynamically adjust the power of the optical signal according to the monitoring distance; The optical intensity regulator dynamically adjusts the power of the optical signal by the following formula: ， in, is the laser power after dynamic adjustment, is the initial laser power, is the distance attenuation coefficient, is the frequency loss coefficient, is the frequency, is the transmission distance of the optical signal in the optical fiber, is the frequency loss index, is the feedback coefficient, and Represent the reference signal strength and the received signal strength respectively, is the adjustment coefficient.

2. The optical fiber distributed acoustic wave monitoring system according to claim 1, characterized in that: The signal transmission module comprises: An optical fiber protection sleeve, covering the surface of the optical fiber, comprises an inner shock-resistant material layer and an outer wear-resistant material layer, wherein the inner shock-resistant material layer is a flexible structure, and the outer wear-resistant material layer is a hard coating; Environmental adaptation layer, attached to the outside of the optical fiber protection sleeve.

3. The optical fiber distributed acoustic wave monitoring system according to claim 2, characterized in that: The optical signal receiving module includes a multi-layer filter array for performing multi-band separation filtering on the received optical signal; The multi-layer filter array includes a low-pass filter, a high-pass filter and a band-pass filter, wherein the low-pass filter is used to remove high-frequency interference signals, the high-pass filter is used to suppress low-frequency environmental noise, and the band-pass filter is used to retain effective signals in the target frequency band.

4. The optical fiber distributed acoustic wave monitoring system according to claim 3, characterized in that: The noise reduction module comprises: A noise feature recognition unit is used to analyze the noise characteristics in the original waveform data, identify the high-frequency and low-frequency noise components, and mark the noise frequency range according to the noise feature library to generate noise marking data; An adaptive filtering unit is used to dynamically adjust the filtering parameters according to the noise marker data, and adaptively filter the original waveform data to obtain waveform analysis data; The bandwidth dynamic adjustment unit is used to adjust the bandwidth of the adaptive filter unit when the noise environment changes drastically to obtain the dynamic bandwidth. The dynamic bandwidth is adjusted by the following formula: ， in, is the dynamic bandwidth, is the initial bandwidth, is the signal-to-noise ratio, To adjust the parameters, is the noise threshold, is the adjustment coefficient, and are the ambient noise intensity and the effective noise intensity, is the adjustment factor.

5. The optical fiber distributed acoustic wave monitoring system according to claim 4, characterized in that: The signal demodulation module comprises: The phase demodulation unit is used to extract the phase change information of each sound source from the waveform analysis data and generate phase demodulation data with phase characteristics. The phase demodulation data is realized by the following formula: ， in, is the phase demodulated signal, For the The amplitude of a sound source, For the The frequency of the sound source, is the time variable, For the The initial phase of the sound source, For the The time attenuation coefficient of a sound source is , For the The sound source at time The signal strength at For the The sound source is The signal strength at is the frequency domain signal, is the total number of sound sources; The intensity demodulation unit is used to extract the intensity characteristics of each sound source from the waveform analysis data and generate intensity demodulation data with intensity characteristics. The intensity demodulation data is realized by the following formula: ， in, is the intensity signal after separation, For the The initial strength of the sound source, For the The intensity attenuation coefficient of a sound source, , For the The sound source is at a distance The signal strength at For the The sound source is Signal strength at ; A signal vectorization unit, used for synchronizing the phase demodulation data and the intensity demodulation data in time, and combining the phase characteristics and intensity characteristics of each sound source in time into a characteristic vector; The characteristic signal generating unit is used to summarize the characteristic vectors of different sound sources to form a characteristic matrix and output it as a characteristic signal.

6. The optical fiber distributed acoustic wave monitoring system according to claim 5, characterized in that: The data processing module comprises: A positioning data generating unit, used for dividing the characteristic signals according to the monitoring areas and converting the characteristic signals into preliminary positioning data with spatial position marks; A regional data integration unit is used to integrate the preliminary positioning data of different monitoring areas by analyzing the relative position and intensity changes of the sound source signals in each area to generate regional integrated positioning data; A sound source localization unit, used to integrate the localization data according to the region and determine the sound source localization information of each sound source; The visual positioning generation unit is used to convert the sound source positioning information into visual data with spatial coordinates and time tags.

7. The optical fiber distributed acoustic wave monitoring system according to claim 6, characterized in that: The positioning data generating unit comprises: A signal partition processing unit, used to divide the characteristic signal into a number of signal partitions according to the monitoring area, each signal partition containing characteristic data in the area; A spatial position calibration unit is used to calibrate the position of each signal partition data and add a spatial position mark to each signal partition according to a preset area division strategy; The preliminary positioning data generating unit is used to merge the signal partition data with spatial position marks into a set to generate preliminary positioning data for each monitoring area.

8. The optical fiber distributed acoustic wave monitoring system according to claim 7, characterized in that: The regional data integration unit comprises: A regional feature extraction unit is used to extract the intensity, phase and position characteristics of the sound source signal in each monitoring area according to the preliminary positioning data, and generate a feature data set with regional characteristics; The cross-region matching unit is used to compare and match the sound source features in different monitoring areas between adjacent areas according to the feature data set, associate the cross-region data belonging to the same sound source, and generate a matching data set; A consistency checking unit, used for calculating the time decay rate of each region and screening the matching data set according to the difference of the time decay rate to obtain a consistency calibration data set; The regional integration generation unit is used to merge the sound source data of adjacent regions into a set according to the consistent calibration data set, so as to obtain regional integration data, which includes the preliminary position and regional mark of each sound source.

9. The optical fiber distributed acoustic wave monitoring system according to claim 8, characterized in that: The sound source localization unit comprises: A location determination unit, used to obtain an accurate location data set by performing location calculation on the multi-dimensional features of the sound source according to the regional integration data; The high-precision output generation unit is used to generate sound source localization information based on the precise positioning data set, and the sound source localization information includes time and space coordinate information.

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