Mine disaster underground trapped personnel state information rapid detection system and positioning method

Abstract

The present application relates to the technical field of coal mine safety, in particular to a mine disaster underground trapped personnel state information rapid detection system and positioning method; comprising a communication optical cable laid in an existing coal mine, further comprising an optical fiber distribution box, an optical fiber distributed acoustic sensing system, a measurement and control and data processing system, a display screen and a sound recovery system; the present application applies high-performance optical fiber distributed acoustic sensing technology and wavelet denoising algorithm to mine disaster underground trapped personnel state information rapid detection and positioning, in the detection system, there is only an optical cable in the mine, and the optical cable is a passive device and will not fail due to disasters or secondary disasters, so that the existing communication optical cable laid in the coal mine can be directly used without the need to drill a life-saving borehole, realizing rapid detection of a meter-level high spatial resolution, high sensitivity and full coverage of the disaster area, and real-time detection and positioning of the trapped personnel and movement in the disaster area.

Description

Technical Field

[0001] This invention relates to the field of coal mine safety technology, specifically to a rapid detection system and positioning method for the status information of trapped personnel underground in mine disasters. Background Technology

[0002] Mine disasters mainly include roof falls, gas and dust explosions, gas outbursts, fires, and water inrushes. When a mine disaster occurs, miners are trapped underground. If rescuers fail to locate and rescue the trapped miners in time, they may miss the optimal rescue window and suffer injury or death. Therefore, timely and effective detection of the trapped miners' condition, implementation of rescue measures, and mitigation of the disaster are the core of rescue work. After a coal mine disaster, the affected area loses power, the mine is filled with large amounts of harmful substances such as gas and dust, and secondary disasters are always a possibility. The environment is extremely complex and harsh. Therefore, how to detect and locate trapped miners is a key research area in the field of mine rescue.

[0003] Existing mine-trapped personnel detection devices can detect personnel's condition, posture, and location through life-saving boreholes. These devices are based on certain electrical principles, such as using sensors that detect electromagnetic waves, sound waves, visible light, and infrared light to convert physical signals into electrical signals. After filtering and amplification, the analog electrical signals are converted into digital signals by a data acquisition system, providing visual output curves, or converting digital signals into analog signals to output directly recognizable audio and video. Using these electrical detection devices to locate trapped personnel underground can effectively rescue them. However, currently, these instruments all use electrical principles, and the equipment used requires intrinsic safety certification before it can be deployed underground. Furthermore, in the harsh environment of mine disasters, they are not resistant to corrosion, easily become damp and malfunction, and are susceptible to electromagnetic interference, making them unstable. More importantly, the detector can only be lowered into the mine after a life-saving borehole has been drilled from the surface into the disaster area. Since it takes several days from the time the drilling rig arrives at the construction site, experts analyze the possible locations of trapped personnel, design and construct the borehole based on the analysis results, until the life-saving borehole is completed, the detector's timeliness is poor, easily missing the optimal rescue time. Moreover, this type of detector can only detect the area near the life-saving borehole, providing only localized detection and not full coverage of the disaster area.

[0004] In conclusion, developing a rapid detection system and positioning method for the status information of trapped personnel underground in mine disasters remains a critical issue that urgently needs to be addressed in the field of coal mine safety technology. Summary of the Invention

[0005] To address the aforementioned shortcomings of existing technologies, this invention provides a rapid detection system and method for the status information of trapped personnel in mine disasters. This invention applies high-performance fiber-optic distributed acoustic sensing technology and wavelet denoising algorithms to the rapid detection and location of trapped personnel's status information in mine disasters. In the detection system, only optical cables exist underground. Since optical cables are passive devices, they will not fail due to disasters or secondary disasters. Therefore, it is possible to directly utilize existing underground communication optical cables in coal mines without needing to drill rescue boreholes, achieving meter-level high spatial resolution, high sensitivity, and rapid detection of the disaster area with full coverage. It can detect and locate trapped personnel and their movement in the disaster area in real time. Its characteristics include: direct utilization of existing underground optical cables, good timeliness; full coverage detection of the disaster area; strong survivability in the harsh environment of mine disasters; immunity to electromagnetic interference, stable and reliable performance; ability to reproduce any sounds emitted by trapped personnel underground, including conversations; and acquisition of key information such as the vital signs and movement of trapped personnel, effectively guiding rescue efforts.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A rapid detection system for the status of trapped personnel in mine disasters includes existing underground communication optical cables, each comprising multiple optical fibers distributed throughout the mine. The system also includes an optical fiber junction box, an optical fiber distributed acoustic wave sensing system, a measurement and control and data processing system, a display screen, and a sound restoration system. The existing underground communication optical cables are connected to the front end of the optical fiber junction box. The front end of the optical fiber distributed acoustic wave sensing system is connected to the rear end of the optical fiber junction box. The rear end of the optical fiber distributed acoustic wave sensing system is connected to the input front end of the measurement and control and data processing system. The output back end of the measurement and control and data processing system is connected in parallel to the display screen and the sound restoration system.

[0008] The present invention is further configured such that: the fiber optic junction box includes a back-end fiber optic interface, a back-end data interface, a split control module, and a flange; the flange is provided with 32 front-end fiber optic interfaces; the split control module obtains instructions through the back-end data interface; the back-end fiber optic interface is connected to a front-end fiber optic interface specified by the instruction via an optical fiber; and the flange is connected to the fiber optic head end of the communication optical cable.

[0009] The present invention is further configured such that: the fiber optic distributed acoustic wave sensing system includes a laser and an optical emission module and an optical detection module connected in parallel to its output end; the optical emission module is composed of an optical fiber coupler, an acousto-optic modulator, an erbium-doped fiber amplifier and a first port of a circulator connected in sequence; the optical detection module is composed of a second port of a circulator, a polarization diversity receiver and a first balanced photodetector and a second balanced photodetector connected in sequence.

[0010] The present invention is further configured such that: the measurement and control and data processing system includes a data processing system composed of a GPU and a CPU, a measurement and control core unit FPGA circuit module, and a DAC circuit module and an ADC circuit module connected in parallel therewith. The DAC circuit module includes a DAC circuit and a radio frequency amplifier circuit. The DAC circuit is connected to the control port in the measurement and control core unit FPGA circuit module. The radio frequency amplifier circuit is connected to the acousto-optic modulator via a coaxial cable. The ADC circuit module is connected to the first balanced photodetector and the second balanced photodetector via a coaxial cable.

[0011] The present invention is further configured such that the display screen is connected to the back end of the measurement, control and data processing system.

[0012] The present invention is further configured such that the sound restoration system is connected to the back end of the measurement, control and data processing system.

[0013] This invention also provides a method for rapid detection and location of the status information of trapped personnel underground in mine disasters, comprising the following steps:

[0014] (1) Based on the disaster-affected area determined by the rescue experts, the optical fibers of the existing underground communication optical cables in the optical cable corresponding to the area will be connected to the interfaces on the flanges of the optical fiber distribution boxes respectively.

[0015] (2) Set the total number of optical fibers connected to the detection system on the measurement and control and data processing system, and control the optical fiber distribution box to connect the optical fibers deployed in the mine disaster-affected area to the front end of the optical fiber distributed acoustic wave sensing system in turn at a certain time interval, such as 2s.

[0016] (3) The laser is modulated to form a linear sweep frequency optical pulse. After the optical power is enhanced by the erbium-doped fiber amplifier, it is sent into the fiber under test. The backscattered Rayleigh signal generated by the transmission beats the laser generated by the optical emission module. The beat frequency optical signal is converted into an electrical signal and demodulated to obtain the acoustic data of the trapped personnel in the area affected by the mine disaster.

[0017] (4) The FPGA circuit module of the measurement and control core unit is used to perform real-time matching filtering on the collected acoustic data stream and the rotating vector averaging algorithm is used to eliminate the influence of coherent fading noise. Then, phase space differential operation is performed to eliminate the influence of laser source phase noise and obtain differential phase information at each location of the optical fiber in the disaster-affected area in real time.

[0018] (5) Use a high-pass filter to filter the differential phase information obtained by demodulation in step (4) to remove low-frequency drift;

[0019] (6) Perform wavelet denoising on the differential phase information after high-pass filtering. Perform wavelet decomposition on the noisy signal. By selecting an appropriate threshold, perform threshold processing on the high-frequency components of each decomposition layer to remove wavelet coefficients with high noise ratios and retain wavelet coefficients controlled by the signal. Finally, reconstruct the denoised signal from these wavelet coefficients.

[0020] (7) The reconstructed and denoised signal is sent to the sound restoration system output. Rescue experts continuously listen to the sounds emitted from the area affected by the mine disaster. Once a sound is detected, the location button is immediately clicked. The detection system finds the corresponding optical fiber of the detected sound through the specified waveform position and further calculates the specific optical fiber position of the sound. By checking the information on the underground optical cable layout, the location of the trapped personnel is determined.

[0021] (8) Repeat steps (3)-(7) to detect all trapped personnel in the affected area of ​​the mine disaster, locate the trapped personnel, and track the movement trajectory of the trapped personnel.

[0022] The present invention is further configured such that, in step (1), the number of optical fibers shall not exceed 32.

[0023] The present invention is further configured such that, in step (5), the cutoff frequency of the high-pass filter is 125 Hz, the lowest frequency that can be heard by the human ear in clinical hearing tests.

[0024] Beneficial effects

[0025] Compared with known public technologies, the technical solution provided by this invention has the following beneficial effects:

[0026] (1) The detection system of the present invention uses the optical cable already laid in the mine as a distributed sensor, which can directly detect without drilling life rescue holes, greatly shortening the detection and positioning time of trapped personnel and gaining golden time for rescue.

[0027] (2) The present invention switches one optical fiber at certain intervals, such as 2 seconds, and takes turns to detect all optical fibers in the disaster-affected area. It can fully cover the detection of sound wave information containing the life information of trapped people in the disaster-affected area. Therefore, the system can not only locate trapped people, but also track the activity trajectory of trapped people and optimize the rescue plan in real time.

[0028] (3) In the detection system of the present invention, only optical fibers are deployed in the mine as distributed sensors. Since optical fibers are passive devices, they will not fail due to disasters and secondary disasters, thus improving safety.

[0029] (4) In the detection system of the present invention, only optical fiber is exposed as a distributed sensor in the harsh environment of mine disasters, and its survivability is very strong.

[0030] (5) In the detection system of the present invention, only the optical fiber is exposed as a distributed sensor in the harsh environment of mine disasters. It is not affected by electromagnetic interference, is not afraid of corrosion, and does not fail when exposed to moisture. Therefore, it is reliable and stable.

[0031] (6) The detection system of the present invention uses the optical cable already laid in the mine as a distributed sensor, which can directly detect without drilling life rescue holes, greatly reducing the detection cost. Attached Figure Description

[0032] Figure 1 A schematic diagram of a rapid detection system for the status information of personnel trapped underground in mine disasters;

[0033] Figure 2 This is a connection diagram of a rapid detection system for the status information of people trapped underground in mine disasters.

[0034] Explanation of the labels in the diagram:

[0035] 1. Fiber-optic distributed acoustic wave sensing system; 11. Laser; 12. Fiber-optic coupler; 13. Acousto-optic modulator; 14. Erbium-doped fiber amplifier; 15. Circulator; 16. Polarization diversity receiver; 17. First balanced photodetector; 18. Second balanced photodetector;

[0036] 2. Measurement and control and data processing system; 21. Radio frequency amplifier circuit; 22. DAC circuit; 23. ADC circuit; 24. Measurement and control core unit FPGA circuit module; 25. Data processing system; 3. Display screen; 4. Sound restoration system; 5. Fiber optic junction box; 51. Back-end fiber optic interface; 52. Back-end data interface; 53. Branch control module; 54. Flange; 6. Communication optical cable; 601. First fiber optic cable in the disaster-affected area; 632. Thirty-second fiber optic cable in the disaster-affected area; 7. Coal mine underground production system. Detailed Implementation

[0037] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0038] In the description of this invention, it should be noted that the terms "upper," "lower," "inner," "outer," "top / bottom," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0039] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installed," "equipped with," "sleeved / connected," "connected," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0040] Example 1:

[0041] Please refer to Figure 1-2 As shown, the rapid detection system for the status information of trapped personnel in mine disasters includes an existing underground communication optical cable 6, which comprises multiple optical fibers distributed throughout the mine. It also includes an optical fiber junction box 5, an optical fiber distributed acoustic wave sensing system 1, a measurement and control and data processing system 2, a display screen 3, and a sound restoration system 4. The existing underground communication optical cable 6 is connected to the front end of the optical fiber junction box 5. The front end of the optical fiber distributed acoustic wave sensing system 1 is connected to the back end of the optical fiber junction box 5. The back end of the optical fiber distributed acoustic wave sensing system 1 is connected to the front end of the measurement and control and data processing system 2. The back end of the measurement and control and data processing system 2 is connected in parallel to the display screen 3 and the sound restoration system 4.

[0042] In this embodiment, up to 32 optical fibers can be connected to the communication optical cable 6 at one time, such as the first optical fiber 601 to the 32nd optical fiber 632 in the disaster-affected area. The communication optical cable 6 is connected to the underground coal mine production system 7. Each 1m of optical fiber deployed in the disaster-affected area of ​​the underground coal mine is equivalent to one acoustic wave detection sensor. The detection system uses the optical cables already deployed in the mine as distributed sensors, and can directly detect without drilling life rescue holes, which greatly shortens the detection and positioning time of trapped personnel and buys golden time for rescue.

[0043] In this invention, the fiber optic splitter box 5 includes a back-end fiber optic interface 51, a back-end data interface 52, a splitter control module 53, and a flange 54. The flange 54 is provided with 32 front-end fiber optic interfaces. The splitter control module 53 obtains instructions through the back-end data interface 52. The back-end fiber optic interface 51 is connected to a certain front-end fiber optic interface specified by the instructions through an optical fiber. The flange 54 is connected to the fiber optic head end of the communication optical cable 6.

[0044] In this embodiment, the flange 54 is provided with 32 front-end fiber optic interfaces, enabling the flange 54 to connect 32 optical fibers at a time.

[0045] In this invention, the fiber optic distributed acoustic wave sensing system 1 includes a laser 11 and a light emitting module and a light detection module connected in parallel to its output end. The light emitting module is composed of a fiber optic coupler 12, an acousto-optic modulator 13, an erbium-doped fiber amplifier 14 and a first port of a circulator 15 connected in sequence. The light detection module is composed of a second port of a circulator 15, a polarization diversity receiver 16 and a first balanced photodetector 17 and a second balanced photodetector 18 connected in sequence.

[0046] In this embodiment, the laser emitted by the laser 11 is coupled into the optical fiber through the optical fiber coupler 12. Then, the measurement and control and data processing system 2 controls the acousto-optic modulator 13 to modulate the laser in the optical fiber into a linear sweep frequency optical pulse. The erbium-doped fiber amplifier 14 enhances its optical power and sends it into the optical fiber under test for forward transmission. The continuously generated backscattered Rayleigh light signal beats with the light pulse generated by the optical emission module. By converting the beat frequency optical signal into an electrical signal and demodulating it, acoustic wave data containing the status of trapped personnel in the area affected by the mine disaster is obtained.

[0047] In this invention, the measurement and control and data processing system 2 includes a data processing system 25 composed of a GPU and a CPU, a measurement and control core unit FPGA circuit module 24, and a DAC circuit module and an ADC circuit module connected in parallel with it. The DAC circuit module includes a DAC circuit 22 and a radio frequency amplifier circuit 21. The DAC circuit 22 is connected to the control port in the measurement and control core unit FPGA circuit module 24. The radio frequency amplifier circuit 21 is connected to the acousto-optic modulator 13 through a coaxial cable. The ADC circuit module 23 is connected to the first balanced photodetector 17 and the second balanced photodetector 18 through a coaxial cable.

[0048] In this embodiment, the radio frequency amplifier circuit 21 is connected to the acousto-optic modulator 13 via a coaxial cable to modulate the laser into a linear sweep frequency optical pulse, thereby realizing the modulation of the laser into a linear sweep frequency optical pulse.

[0049] In this invention, the display screen 3 is connected to the back end of the measurement and control and data processing system 2.

[0050] In this embodiment, the processed information data can be displayed on the screen 3 so that staff can refer to the processed data information.

[0051] In this invention, the sound restoration system 4 is connected to the back end of the measurement, control and data processing system 2.

[0052] In this embodiment, rescue experts continuously monitor the sounds emitted from the area affected by the mine disaster and locate the optical fiber corresponding to the detected sound by identifying the specified waveform position.

[0053] Example 2:

[0054] Based on Example 1, the present invention also provides a method for rapid detection and location of the status information of trapped personnel underground in mine disasters, including the following steps:

[0055] (1) Based on the disaster-affected area determined by the rescue experts, the optical fibers of the existing underground communication optical cable 6 in the optical cable corresponding to the area will be connected to the interface on the flange 54 of the optical fiber junction box 5 respectively. The number of optical fibers shall not exceed 32.

[0056] (2) Set the total number of optical fibers connected to the detection system on the measurement and control and data processing system 2, and control the optical fiber distribution box 5 to connect the optical fibers deployed in the mine disaster-affected area to the front end of the optical fiber distributed acoustic wave sensing system 1 in turn at a certain time interval, such as 2s.

[0057] (3) The laser is modulated to form a linear sweep frequency optical pulse. After the optical power is enhanced by the erbium-doped fiber amplifier 14, it is sent into the optical fiber under test. The backscattered Rayleigh signal generated by the transmission beats the laser generated by the optical emission module. The beat frequency optical signal is converted into an electrical signal and demodulated to obtain the acoustic data containing the state of trapped personnel in the area affected by the mine disaster.

[0058] (4) In order to obtain Rayleigh scattering signals at various locations along the optical fiber in real time, the FPGA circuit module 24 of the measurement and control core unit is used to perform real-time matching filtering on the collected acoustic data stream, and the rotating vector averaging algorithm is used to process it to eliminate the influence of coherent fading noise. Then, phase space differential operation is performed to eliminate the influence of laser source phase noise and obtain differential phase information at various locations of the optical fiber in the disaster-affected area in real time.

[0059] (5) Use a high-pass filter to filter the differential phase information obtained by demodulation in step (4) to filter out low-frequency drift. The cutoff frequency of the high-pass filter is 125Hz, the lowest frequency that the human ear can hear in clinical hearing tests.

[0060] (6) Wavelet denoising is performed on the differential phase information after high-pass filtering. Wavelet decomposition is performed on the noisy signal. The high-frequency coefficients obtained contain both useful signals and noise. Since the noise coefficients are relatively small while the useful signal wavelet coefficients are relatively large, a suitable threshold is selected to perform threshold processing on the high-frequency components of each decomposition layer, removing wavelet coefficients with high noise ratios and retaining wavelet coefficients controlled by the signal. Finally, the denoised signal is reconstructed from these wavelet coefficients.

[0061] (7) The reconstructed and denoised signal is sent to the sound restoration system 4 output. The rescue experts continuously listen to the sounds emitted from the area affected by the mine disaster. Once a sound is detected, the positioning button is immediately clicked. The detection system finds the corresponding optical fiber of the detected sound through the specified waveform position and further calculates the specific optical fiber position of the sound. The location of the trapped personnel is determined by checking the underground optical cable layout information.

[0062] (8) Repeat steps (3)-(7) to detect all trapped personnel in the affected area of ​​the mine disaster, locate the trapped personnel, and track the movement trajectory of the trapped personnel.

[0063] This invention applies high-performance fiber-optic distributed acoustic sensing technology and wavelet denoising algorithm to the rapid detection and location of trapped personnel in mine disasters. In the detection system, only optical cables exist underground. Since optical cables are passive devices, they will not fail due to disasters or secondary disasters. It can directly utilize existing underground communication optical cables in coal mines to achieve meter-level high spatial resolution, high sensitivity, and rapid detection of disaster-stricken areas with full coverage without the need for life-saving drilling. It can detect and locate trapped personnel and their movement in disaster-stricken areas in real time.

[0064] Various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented in any one or a combination thereof of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

Claims

1. A rapid detection system for the status information of trapped personnel in mine disasters, comprising existing communication optical cables deployed underground in coal mines, wherein the communication optical cables include multiple optical fibers distributed underground in the coal mine, characterized in that... It also includes an optical fiber junction box, an optical fiber distributed acoustic wave sensing system, a measurement and control and data processing system, a display screen, and a sound restoration system. The existing communication optical cable deployed in the coal mine is connected to the front end of the optical fiber junction box. The front end of the optical fiber distributed acoustic wave sensing system is connected to the back end of the optical fiber junction box. The back end of the optical fiber distributed acoustic wave sensing system is connected to the front end of the measurement and control and data processing system. The back end of the measurement and control and data processing system is connected in parallel to the display screen and the sound restoration system. The fiber optic splitter box includes a back-end fiber optic interface, a back-end data interface, a splitter control module, and a flange. The flange is equipped with 32 front-end fiber optic interfaces. The splitter control module obtains instructions through the back-end data interface. The back-end fiber optic interface is connected to a front-end fiber optic interface specified by the instruction via an optical fiber. The flange is connected to the fiber optic head end of the communication optical cable. The fiber optic distributed acoustic wave sensing system includes a laser and an optical emission module and an optical detection module connected in parallel to its output end. The optical emission module is composed of an optical fiber coupler, an acousto-optic modulator, an erbium-doped fiber amplifier and a first port of a circulator connected in sequence. The optical detection module is composed of a second port of a circulator, a polarization diversity receiver and a balanced photodetector connected in sequence. The total number of optical fibers connected to the detection system is set on the measurement, control and data processing system. At 2-second intervals, the optical fiber distribution box is controlled to connect the optical fibers deployed in the disaster-affected area of ​​the mine to the front end of the optical fiber distributed acoustic wave sensing system in turn.

2. The rapid detection system for the status information of trapped personnel in mine disasters according to claim 1, characterized in that, The measurement and control and data processing system includes a data processing system composed of a GPU and a CPU, a measurement and control core unit FPGA circuit module, and an ADC circuit module and a DAC circuit module connected in parallel with it. The DAC circuit module includes a DAC circuit and a radio frequency amplifier circuit. The DAC circuit is connected to the control port in the measurement and control core unit FPGA circuit module. The radio frequency amplifier circuit is connected to the acousto-optic modulator via a coaxial cable. The ADC circuit module is connected to the balanced photodetector via a coaxial cable.

3. The rapid detection system for the status information of trapped personnel in mine disasters according to claim 1, characterized in that, The display screen is connected to the back end of the measurement, control and data processing system.

4. The rapid detection system for the status information of trapped personnel in mine disasters according to claim 1, characterized in that, The sound restoration system is connected to the back end of the measurement, control and data processing system.

5. A method for rapid detection and location of the status information of trapped personnel underground in mine disasters, characterized in that, The rapid detection system for the status information of trapped personnel in mine disasters, as described in any one of claims 1-4, includes the following steps: (1) Based on the disaster-affected area determined by the rescue experts, the optical fiber of the existing underground communication optical cable in the optical cable corresponding to the area will be connected to the interface on the flange of the optical fiber junction box respectively. (2) Set the total number of optical fibers connected to the detection system on the measurement and control and data processing system, and control the optical fiber distribution box to connect the optical fibers deployed in the mine disaster-affected area to the front end of the optical fiber distributed acoustic wave sensing system in turn at a time interval of 2s. (3) The laser is modulated to form a linear sweep frequency optical pulse. After the optical power is enhanced by the erbium-doped fiber amplifier, it is sent into the fiber under test. The backscattered Rayleigh signal generated by the transmission beats the laser generated by the optical emission module. The beat frequency optical signal is converted into an electrical signal and demodulated to obtain the acoustic data of the trapped personnel in the area affected by the mine disaster. (4) The FPGA circuit module of the measurement and control core unit is used to perform real-time matching filtering on the collected acoustic data stream and the rotating vector averaging algorithm is used to eliminate the influence of coherent fading noise. Then, phase space differential operation is performed to eliminate the influence of laser source phase noise and obtain differential phase information at each location of the optical fiber in the disaster-affected area in real time. (5) Use a high-pass filter to filter the differential phase information obtained by demodulation in step (4) to remove low-frequency drift; (6) Perform wavelet denoising on the differential phase information after high-pass filtering. Perform wavelet decomposition on the noisy signal. By selecting an appropriate threshold, perform threshold processing on the high-frequency components of each decomposition layer to remove wavelet coefficients with high noise ratios and retain wavelet coefficients controlled by the signal. Finally, reconstruct the denoised signal from these wavelet coefficients. (7) The reconstructed and denoised signal is sent to the sound restoration system output. Rescue experts continuously listen to the sounds emitted from the area affected by the mine disaster. Once a sound is detected, the location button is immediately clicked. The detection system finds the corresponding optical fiber of the detected sound through the specified waveform position and further calculates the specific optical fiber position of the sound. The location of the trapped personnel is determined by checking the underground optical cable layout information. (8) Repeat steps (3)-(7) to detect all trapped personnel in the affected area of ​​the mine disaster, locate the trapped personnel, and track the movement trajectory of the trapped personnel.

6. The method for rapid detection and location of the status information of trapped personnel underground in mine disasters according to claim 5, characterized in that, In step (1), the number of optical fibers shall not exceed 32.

7. The method for rapid detection and location of the status information of trapped personnel underground in mine disasters according to claim 6, characterized in that, In step (5), the cutoff frequency of the high-pass filter is 125 Hz, which is the lowest frequency that the human ear can hear in clinical hearing tests.

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