Early fire point remote sensing detection method, device and system

Abstract

The invention discloses a remote sensing detection method, device and system for an early fire point, and the method comprises the steps: controlling an aerosol laser radar to scan a target region, and judging whether an aerosol plume exists in the target region or not according to the spatial and temporal distribution of aerosol; when the aerosol plume exists in the target area, the CO2 laser radar is controlled to carry out CO2 concentration detection on the scanning area where the aerosol plume is located, one or more concentration profiles are obtained, CO2 concentration distribution is determined according to the CO2 concentration profiles, and whether a CO2 high-value area exists in the area where the aerosol plume is located or an adjacent area or not is judged according to the CO2 concentration distribution. And when the CO2 high-value area exists in the area where the aerosol plume is located or the adjacent area, the occurrence position of the fire behavior is determined according to the area where the aerosol plume and / or the CO2 high-value area is located. By detecting the joint distribution of the aerosol plume and the CO2 high-value region, the interference of aerosol particles such as cloud and mist is eliminated, the influence of carbon sources such as vegetation can also be eliminated, and the problems of low early fire point recognition accuracy and slow response speed are solved.

Description

Technical Field

[0001] The present application relates to the field of fire monitoring, and in particular to a remote sensing detection method, device and system for early fire points. Background Art

[0002] In wide-ranging and remote natural areas, such as forests, mountains, grasslands and other environments, it is impossible to accurately determine the specific location, intensity, range and other information of early fire points by relying solely on manual and sensor means, and it consumes a lot of manpower and material resources. Satellite remote sensing uses satellites equipped with multiple sensors to observe the surface, which is suitable for large-scale, long-term global monitoring. Due to factors such as orbital period, spatial resolution, and weather, the ability to detect early fire points is still insufficient. Drones carry optical cameras or infrared thermal imagers and other equipment to fly on designated routes and times. They are flexible and convenient, but they have disadvantages such as limited detection range, short endurance, and susceptibility to weather. Aerosol lidar is used to monitor fire-prone areas and identify early fire points by detecting the spatiotemporal distribution of particles in fire smoke. It has the advantages of wide coverage, high spatiotemporal resolution, strong timeliness, and all-weather. However, aerosol lidar is interfered by aerosol particles such as clouds and fog, and its recognition accuracy needs to be improved. CO2 LiDAR determines fire conditions by detecting the distribution of CO2 concentration. On the one hand, it is easily interfered by carbon sources such as vegetation. On the other hand, CO2 LiDAR has a long scanning cycle, slow response speed, and low resolution. Especially in the early stages of a fire, the response delay increases the risk of the fire spreading beyond the controllable range.

[0003] In summary, the current methods for detecting early fire points have the problems of low recognition accuracy and slow response speed. Summary of the invention

[0004] The present invention provides a remote sensing detection method, device and system for early fire points to solve the problems of low recognition accuracy and slow response speed in current early fire point detection methods.

[0005] In a first aspect, the present invention provides a remote sensing detection method for early fire points, comprising:

[0006] Controlling an aerosol laser radar to scan a target area, determining the spatiotemporal distribution of aerosols in the target area according to scanning data of the aerosol laser radar, and judging whether there is an aerosol plume in the target area according to the spatiotemporal distribution of aerosols;

[0007] When an aerosol plume exists in the target area, the CO2 laser radar is controlled to detect the CO2 concentration in the scanning area where the aerosol plume is located, a single or multiple concentration profiles are obtained by the CO2 laser radar, the CO2 concentration distribution is determined according to the concentration profiles, and whether there is a high CO2 value area in the area where the aerosol plume is located or in the vicinity is determined according to the CO2 concentration distribution;

[0008] When the CO2 high value area exists in the area where the aerosol plume is located or in the vicinity, the location of the fire is determined based on the area where the aerosol plume and / or the CO2 high value area are located.

[0009] In a second aspect, the present invention provides a remote sensing detection device for early fire points, comprising:

[0010] A first detection module is used to control the aerosol laser radar to scan the target area, and obtain the aerosol spatiotemporal distribution data of the target area from the aerosol laser radar, and determine whether there is an aerosol plume in the target area based on the aerosol spatiotemporal distribution data of the target area;

[0011] The second detection module is used for, when there is an aerosol plume in the target area, controlling the CO2 laser radar to detect the CO2 concentration in the scanning area where the aerosol plume is located, obtaining a single or multiple concentration profiles through the CO2 laser radar, determining the CO2 concentration distribution according to the concentration profiles, and judging whether there is a CO2 high value area in the area where the aerosol plume is located or in the vicinity according to the CO2 concentration distribution;

[0012] The location determination module is used to determine the location of the fire according to the area where the aerosol plume and / or the CO2 high value area are located when the CO2 high value area exists in the area where the aerosol plume is located or in the vicinity.

[0013] In a third aspect, the present invention provides a data processing terminal, comprising a memory and a processor, wherein the memory stores a computer program, and the processor is configured to run the computer program to execute the remote sensing detection method for early fire points described in the first aspect.

[0014] In a fourth aspect, the present invention provides a remote sensing detection system for early fire points, comprising a remote sensing detection device and the data processing terminal described in the third aspect;

[0015] The remote sensing detection device includes at least one aerosol laser radar and at least one CO2 laser radar;

[0016] Alternatively, the remote sensing detection device is a single or multiple CO2 lidars with aerosol detection function, which performs aerosol scanning and then detects CO2 concentration when an aerosol plume is found.

[0017] Compared with the remote sensing detection method of fire points using a single laser radar (such as an aerosol laser radar) in the prior art, the present invention uses two laser radars to perform remote sensing detection of fire points, and determines the fire points through the joint distribution of aerosol plumes and CO2 high-value areas, eliminating the interference of aerosol particles such as clouds and fog, and can also eliminate the influence of carbon sources such as vegetation, thereby improving the detection accuracy of fire points. It should be noted that the scanning mode and scanning cycle are important factors affecting the accuracy and response speed of fire location. Aerosol particles in the atmosphere can produce strong backscattering, while CO2 molecules absorb weakly, requiring multiple scans and signal accumulation to enhance the signal-to-noise ratio. The scanning cycle of aerosol laser radar is short, and the scanning cycle of CO2 laser radar is long. Therefore, the present invention further optimizes the combined scanning mode of the two laser radars. First, use the aerosol laser radar with a short scanning cycle to pre-scan the entire target area, and then use the CO2 laser radar with a long scanning cycle to perform a secondary scan on the scanning area where the smaller aerosol plume is located. The CO2 laser radar samples the concentration of the scanning area where the aerosol plume is located, and obtains a single or multiple concentration profiles. Multiple profiles form a CO2 concentration distribution image. Compared with other areas, the fire point is confirmed based on whether there is a high CO2 value area in the aerosol plume or the adjacent area. This scanning method maximizes the overall laser scanning efficiency and speeds up the response speed of early fire points compared to other combined scanning methods while having a higher fire detection accuracy.

[0018] Therefore, the present invention provides a remote sensing detection method for early fire points with high detection accuracy and high detection efficiency, which solves the problems of low recognition accuracy and slow response speed in current early fire point detection methods.

[0019] Details of one or more embodiments of the present application are set forth in the following drawings and description to make other features, objects, and advantages of the present application more readily apparent. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a flow chart of a remote sensing detection method for early fire points provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0021] In order to more clearly understand the purpose, technical solutions and advantages of the present application, the present application is described and illustrated below in conjunction with the accompanying drawings and embodiments.

[0022] Unless otherwise defined, the technical terms or scientific terms involved in this application shall have the general meaning understood by people with ordinary skills in the technical field to which this application belongs. The words "one", "a", "a", "the", "these" and the like in this application do not represent quantitative restrictions, and they can be singular or plural. The terms "include", "comprise", "have" and any variants thereof involved in this application are intended to cover non-exclusive inclusions; for example, a process, method and system, product or device comprising a series of steps or modules (units) is not limited to the listed steps or modules (units), but may include unlisted steps or modules (units), or may include other steps or modules (units) inherent to these processes, methods, products or devices. The words "connect", "connected", "coupled" and the like involved in this application are not limited to physical or mechanical connections, but may include electrical connections, whether directly or indirectly. The "multiple" involved in this application refers to two or more. "And / or" describes the association relationship of associated objects, indicating that there can be three relationships. For example, "A and / or B" can mean: A exists alone, A and B exist at the same time, and B exists alone. Usually, the character " / " indicates that the objects associated with each other are in an "or" relationship. The terms "first", "second", "third", etc. involved in this application are only used to distinguish similar objects and do not represent a specific ordering of the objects.

[0023] In an embodiment of the present invention, a remote sensing detection method for early fire points is provided. Figure 1 FIG. 1 is a flow chart of a remote sensing detection method for early fire points provided in an embodiment of the present invention. Figure 1 As shown, the process includes the following steps:

[0024] Step S110, controlling the aerosol lidar to scan the target area, determining the aerosol spatiotemporal distribution of the target area according to the scanning data of the aerosol lidar, and judging whether there is an aerosol plume in the target area according to the aerosol spatiotemporal distribution.

[0025] Among them, the target area is the monitored area prone to fire. The scanning data of the aerosol lidar includes the optical parameters of the aerosol particles, including the distance correction signal, extinction coefficient, depolarization ratio and backscattering coefficient. Specifically, the aerosol lidar emits laser to interact with the aerosol in the atmosphere, and the receiving system receives the backscattered echo signal. The distance correction signal, extinction coefficient, depolarization ratio, backscattering coefficient and other optical parameters of the aerosol particles are obtained from the backscattered echo signal by inversion, and the aerosol particles are detected to obtain the spatiotemporal distribution of the aerosol particles, so as to determine the flow of the aerosol in the air, and then it can be judged whether there is an aerosol plume in the target area.

[0026] If there is no aerosol plume in the target area, the detection ends, and step S110 is repeated after one detection cycle. If there is an aerosol plume in the target area, step S120 is executed.

[0027] Step S120, control the CO2 laser radar to detect the CO2 concentration in the scanning area where the aerosol plume is located, obtain a single or multiple concentration profiles through the CO2 laser radar, determine the CO2 concentration distribution according to the concentration profiles of the CO2 laser radar, and judge whether there is a high CO2 value area in the aerosol plume or the adjacent area according to the CO2 concentration distribution.

[0028] Among them, the aerosol plume adjacent area is the peripheral scanning area outside the aerosol plume boundary when the CO2 lidar scans the area where the aerosol plume is located.

[0029] The CO2 high value area is an area where the CO2 concentration in the aerosol plume or the adjacent area is higher than other areas. Generally speaking, when there is no fire, the CO2 concentration in each area is stable and the same. If the CO2 concentration in a certain area increases and is higher than other areas, the area can be defined as a high value area. Correspondingly, a threshold can also be preset, and the CO2 high value area is an area where the CO2 concentration is higher than the threshold.

[0030] Among them, the concentration profile of the CO2 lidar reflects the change in CO2 concentration at each point within the scanning area of ​​the CO2 lidar, from the laser emission center to a certain distance.

[0031] Considering that aerosol lidar is easily disturbed by aerosol particles such as clouds and fog, the mere existence of an aerosol plume does not mean that a fire is likely to have occurred. At the same time, it is considered that when a fire occurs on the surface, the local particulate matter and CO2 gas concentrations caused by the fire significantly exceed the surface emissions under natural conditions, that is, the fire will cause both an aerosol plume and a high-value CO2 area. The present invention determines the scanning area where the aerosol plume is located as a candidate area, and controls the CO2 lidar to repeatedly scan the scanning area where the aerosol plume is located. If there is a high-value CO2 area in the scanning area where the aerosol plume is located, it can be more accurately determined that a fire has occurred.

[0032] Exemplarily, the CO2 laser radar is a differential absorption CO2 laser radar, which emits two or more laser beams of the resonant wavelength and non-resonant wavelength of CO2 during scanning; the scanning data of the CO2 laser radar includes the intensity of the echo signal, the intensity difference of the echo signal, and the distance concentration distribution. The intensity difference of the echo signal reflects the differential absorption of the laser by CO2. Different concentrations of CO2 have different degrees of absorption of the laser. Based on the intensity difference of the echo signal returned at various positions in the scanning area where the aerosol plume is located, the CO2 concentration at various locations in the scanning area where the aerosol plume is located, that is, the spatiotemporal distribution of CO2, can be determined. In this way, the flow of CO2 in the air can be determined, and it can be judged whether there is a high-value CO2 area in the scanning area where the aerosol plume is located. If there is no high-value CO2 area in the area where the aerosol plume is located or adjacent to it, the detection ends, and step S110 is repeated after one detection cycle. If there is a high-value CO2 area in the target area, step S130 is executed.

[0033] Step S130: When there is a high CO2 value area in the scanning area where the aerosol plume is located, the location of the fire is determined according to the area where the aerosol plume and / or the high CO2 value area are located.

[0034] When there is a high CO2 value area in the area where the aerosol plume is located or in the vicinity, that is, there are both an aerosol plume and a high CO2 value area in the target area, the present invention determines that there is a fire in the target area. Further, when a fire occurs, the aerosol plume and the high CO2 value area are usually above the fire point (the location where the fire occurs), and then the location of the fire can be determined based on the area where the detected aerosol plume and / or high CO2 value area is located (the area where the aerosol plume and the high CO2 value area exist at the same time).

[0035] In summary, in order to improve the accuracy of fire detection, the present invention combines two detection methods. First, an aerosol laser radar is used to scan the entire target area to obtain the scanning area where the aerosol plume is located. There may be fire points below or near the area where the aerosol plume is located. On this basis, the CO2 laser radar is used again to scan the scanning area where the aerosol plume is located (not the entire target area) to obtain the CO2 high value area, and then it can be more accurately determined that there are fire points near or below the area.

[0036] Compared with the remote sensing detection method of fire points using a single laser radar (such as an aerosol laser radar) in the prior art, the present invention uses two laser radars to perform remote sensing detection of fire points, and determines the fire points through the joint distribution of aerosol plumes and CO2 high-value areas, eliminating the interference of aerosol particles such as clouds and fog, and can also eliminate the influence of carbon sources such as vegetation, thereby improving the detection accuracy of fire points. It should be noted that the scanning mode and scanning cycle are important factors affecting the accuracy and response speed of fire location. Aerosol particles in the atmosphere can produce strong backscattering, while CO2 molecules absorb weakly, requiring multiple scans and signal accumulation to enhance the signal-to-noise ratio. The scanning cycle of aerosol laser radar is short, and the scanning cycle of CO2 laser radar is long. Therefore, the present invention further optimizes the combined scanning mode of the two laser radars. First, use the aerosol laser radar with a short scanning cycle to pre-scan the entire target area, and then use the CO2 laser radar with a long scanning cycle to perform a secondary scan on the scanning area where the smaller aerosol plume is located. The CO2 laser radar samples the concentration of the scanning area where the aerosol plume is located, obtains a single or multiple concentration profiles, and multiple profiles constitute the CO2 concentration distribution. Compared with other areas, the fire point is confirmed based on whether there is a high CO2 value area in the aerosol plume or the adjacent area. This scanning method maximizes the overall laser scanning efficiency and speeds up the response speed of early fire points compared to other combined scanning methods while having a higher fire detection accuracy.

[0037] Therefore, the present invention provides a remote sensing detection method for early fire points with high detection accuracy and high detection efficiency, which solves the problems of low recognition accuracy and slow response speed in current early fire point detection methods.

[0038] A CO2 high value area with a closed boundary constitutes a CO2 plume. The location of the fire can be determined more accurately based on the shape of the CO2 plume. However, in the process of CO2 laser radar detection, tracking the CO2 plume to form a complete shape will lead to longer scanning time and reduce the efficiency of fire detection. When the CO2 high value area is identified, the fire point is confirmed, which can save monitoring time and speed up the fire response. Of course, in order to confirm the fire point more accurately, the fire point can also be confirmed after the CO2 high value area with a closed boundary is scanned. Therefore, in some embodiments, the CO2 high value area is a CO2 plume (a CO2 high value area with a closed boundary). In other embodiments, the CO2 high value area is a CO2 high value area with an unclosed boundary.

[0039] It should be noted that the aerosol laser radar used in the present invention is a laser radar with an aerosol detection function, and the CO2 laser radar used is a laser radar with a CO2 detection function. Therefore, if there is a laser radar that has both an aerosol detection function and a CO2 detection function, it is both an aerosol laser radar and a CO2 laser radar as referred to in the present invention.

[0040] Based on the spatiotemporal distribution of aerosols and CO2, in addition to determining the location of the fire, other information about the fire can also be determined.

[0041] In some of the embodiments, when there is a high CO2 value area in the scanning area where the aerosol plume is located, the fire spread direction and diffusion path are also determined according to the shape and flow direction of the aerosol plume and / or the high CO2 value area. The horizontal expansion direction of the plume is usually consistent with the wind direction at the fire scene. By observing the plume shape and flow direction in continuous scanning cycles, the fire spread direction and diffusion path can be determined.

[0042] In some of the embodiments, when there is a high CO2 value area in the scanning area where the aerosol plume is located, the fire occurrence area is also determined according to the size of the aerosol plume and / or the high CO2 value area. Generally, the size of the fire is positively correlated with the size of the plume, that is, the larger the plume, the larger the fire occurrence area.

[0043] In some of the embodiments, when there is a high CO2 value area in the scanning area where the aerosol plume is located, the trend of the fire is also determined according to the changes in the aerosol plume and / or the high CO2 value area. In combination with the above two embodiments, the change trend of the fire diffusion direction and diffusion path can be determined by the change in the plume shape and flow direction. And the change trend of the fire size can be determined by the change in the plume size.

[0044] In some of the embodiments, when there is a high CO2 value area in the scanning area where the aerosol plume is located, a fire alarm is sent and the location of the fire is displayed. Correspondingly, in the above embodiments, information such as the area of ​​occurrence, diffusion direction, diffusion path and trend of the fire can also be displayed.

[0045] In the embodiments of the present invention, a remote sensing detection device for early fire points is also provided, which is used to implement the above embodiments and preferred implementation modes, and the descriptions that have been made will not be repeated. The terms "module", "unit", "subunit", etc. used below can implement a combination of software and / or hardware for a predetermined function. Although the devices described in the following embodiments are preferably implemented in software, the implementation of hardware, or a combination of software and hardware, is also possible and conceivable.

[0046] Remote sensing detection devices for early fire points include:

[0047] The first detection module is used to control the aerosol lidar to scan the target area, and obtain the aerosol spatiotemporal distribution data of the target area from the aerosol lidar, and judge whether there is an aerosol plume in the target area based on the aerosol spatiotemporal distribution data of the target area.

[0048] The second detection module is used for controlling the CO2 laser radar to detect the CO2 concentration in the scanning area where the aerosol plume is located when there is an aerosol plume in the target area, obtaining a single or multiple concentration profiles through the CO2 laser radar, determining the CO2 concentration distribution according to the concentration profiles, and judging whether there is a high CO2 value area in the area where the aerosol plume is located or in the vicinity according to the CO2 concentration distribution;

[0049] The CO2 high value area is the area where the aerosol plume is located or adjacent to the area, where the CO2 concentration distribution shows an increase in concentration compared to other areas.

[0050] The location determination module is used to determine the location of the fire according to the area where the aerosol plume and / or the CO2 high value area is located when there is a CO2 high value area in the area where the aerosol plume is located or in the vicinity.

[0051] Compared with the remote sensing detection method of fire points using a single laser radar (such as an aerosol laser radar) in the prior art, the present invention uses two laser radars to perform remote sensing detection of fire points, determines the fire points through the joint distribution of aerosol plumes and CO2 high-value areas, eliminates interference from cloud particles, and can also eliminate the influence of carbon sources such as vegetation, thereby improving the detection accuracy of fire points. It should be noted that the scanning mode and scanning cycle are important factors affecting the accuracy and response speed of fire location. Aerosol particles in the atmosphere can produce strong backscattering, while CO2 molecules absorb weakly, requiring multiple scans and signal accumulation to enhance the signal-to-noise ratio. The scanning cycle of aerosol laser radar is short, and the scanning cycle of CO2 laser radar is long. Therefore, the present invention further optimizes the combined scanning mode of the two laser radars. First, use the aerosol laser radar with a short scanning cycle to pre-scan the entire target area, and then use the CO2 laser radar with a long scanning cycle to perform a secondary scan on the scanning area where the smaller aerosol plume is located. Compared with other combined scanning methods, this scanning method maximizes the overall laser scanning efficiency and speeds up the response to early fire points while having higher fire detection accuracy.

[0052] Therefore, the present invention provides a remote sensing detection device for early-stage fire points with high detection accuracy and high detection efficiency, which solves the problems of low recognition accuracy and slow response speed in current early-stage fire point detection methods.

[0053] It should be noted that the above modules can be functional modules or program modules, and can be implemented by software or hardware. For modules implemented by hardware, the above modules can be located in the same processor; or the above modules can be located in different processors in any combination.

[0054] In an embodiment of the present invention, a data processing terminal is also provided, including a memory and a processor, wherein a computer program is stored in the memory, and the processor is configured to run the computer program to execute the remote sensing detection method for early fire points provided by the present invention.

[0055] In an embodiment of the present invention, a remote sensing detection system for early fire points is also provided, including a remote sensing detection device and a data processing terminal provided by the present invention.

[0056] In some of the embodiments, the remote sensing detection device includes at least one aerosol lidar and at least one CO2 lidar.

[0057] In other embodiments, the remote sensing detection device is a single or multiple CO2 laser radars with aerosol detection function. After aerosol scanning, when an aerosol plume is found, CO2 concentration detection is performed.

[0058] The processor in the data processing terminal is used to execute the remote sensing detection method for early fire points provided by the present invention. Therefore, the various embodiments of the remote sensing detection system for early fire points refer to the various embodiments of the remote sensing detection method in the present invention.

[0059] As follows, a specific embodiment of a remote sensing detection system for early fire points is provided to further illustrate the remote sensing detection system and remote sensing detection method of the present invention.

[0060] In one embodiment, the remote sensing detection system for early fire points mainly includes a remote sensing detection module (remote sensing detection device), a plume identification module, a fire point identification module and a fire alarm module (the three together perform a remote sensing detection method).

[0061] The remote sensing detection module includes an aerosol lidar and a carbon dioxide lidar. First, the aerosol lidar pre-scans the fire-prone area (target area) to obtain the spatiotemporal distribution of aerosols in the fire-prone area. Subsequently, the carbon dioxide lidar sets the scanning range of the carbon dioxide lidar through the aerosol plume contour boundary, repeatedly scans one or more aerosol plumes at a small angle, and draws the CO2 spatiotemporal distribution data of the scanning area where the aerosol plume is located.

[0062] Aerosol lidar emits laser to interact with aerosols in the atmosphere. The receiving system receives the backscattered echo signal and obtains the distance correction signal, extinction coefficient, depolarization ratio, backscattering coefficient and other optical parameters of the aerosol particles from the backscattered echo signal through inversion, thereby detecting atmospheric particles and obtaining the spatiotemporal distribution of particles.

[0063] According to the different absorption properties of CO2 to laser pulses, the differential absorption CO2 lidar emits two or more laser beams of specific wavelengths simultaneously or at a certain time interval along the same laser transmission path. One wavelength is the resonant wavelength of carbon dioxide, located at the carbon dioxide absorption peak; the other wavelength is the non-resonant wavelength of carbon dioxide, located at the carbon dioxide absorption valley. The distance-concentration information of the gas to be measured is solved based on the light intensity difference of the echo signal.

[0064] It is worth noting that the scanning range of aerosol lidar and carbon dioxide lidar should cover fire-prone areas at the same time, showing horizontal scanning images of CO2 and aerosol particles, reflecting the horizontal distribution and diffusion trajectory of fire plumes.

[0065] It is worth noting that the scanning mode and scanning cycle are important factors affecting the accuracy of fire location and the response speed. The concentration of aerosol particles in the atmosphere is relatively high, and the backscattering intensity of the laser is obvious. Unlike aerosols, CO2 is a gas, and its response to the emitted laser is mainly absorption rather than scattering. Its radar signal is weak, and multiple cumulative measurements are required to improve the signal-to-noise ratio. Compared with aerosol lidar, carbon dioxide lidar has a long scanning cycle. Aerosol lidar can quickly detect the boundary and position of aerosol plumes, and effectively exclude areas where there is no fire in the scanning area. The subsequent carbon dioxide lidar performs a small-angle scan to detect CO2 gas based on the scanning area where the aerosol plume marked by the aerosol lidar is located. The CO2 lidar performs concentration sampling on the scanning area where the aerosol plume is located to obtain a single or multiple concentration profiles. The CO2 concentration profile constitutes the CO2 concentration distribution. Compared with other areas, the concentration of CO2 concentration distribution in the aerosol plume or adjacent areas is increased to confirm the fire point, so as to improve the fire response speed.

[0066] It is worth noting that the remote sensing detection module may include one or more aerosol lidars and carbon dioxide lidars; the functions of the aerosol lidar and the carbon dioxide lidar may also be integrated into a whole to achieve the function of measuring the spatiotemporal distribution of aerosols and CO2 in fire-prone areas.

[0067] The plume identification module receives the aerosol lidar and carbon dioxide lidar scanning data from the remote sensing detection module; corresponds the scanned image pixels to the GIS geographic space, and displays the real geographic coordinate information of each pixel; establishes a database to remove hot spots caused by non-fire reasons such as hard targets.

[0068] The plume recognition module acquires the particle scanning data in real time, and inverts and obtains optical parameters such as backscattering coefficient, distance correction signal, depolarization ratio, extinction coefficient, etc. Based on the above optical parameters, the position distribution, quantity, contour, contour boundary and other information of the aerosol plume in the aerosol lidar scanning image are identified. The plume recognition module acquires CO2 scanning data in real time, and identifies the position distribution, quantity, contour, contour boundary and other information of the CO2 high value area in the carbon dioxide lidar scanning image.

[0069] It is worth noting that in the plume identification module, when a fire occurs on the ground, the local particulate matter and CO2 gas concentrations caused by the fire significantly exceed the surface emissions under natural conditions. In the aerosol and CO2 lidar scanning images, particulate matter and CO2 gas are significantly different from the surrounding natural background. By comparing the concentration differences in the scanning images, aerosol plumes and high CO2 value areas in the atmosphere can be identified.

[0070] The fire point positioning module receives the aerosol plume and CO2 high value area in the plume identification module, and realizes the identification and positioning of the early fire point according to the information of the aerosol plume and CO2 high value area. If the aerosol plume and CO2 high value area exist at the same position in a continuous scanning cycle, the interference of aerosol particles such as clouds and fog can be eliminated, and the influence of carbon sources such as vegetation can also be eliminated. According to the spatial information of geographic information, the location of the early fire point is identified to improve the positioning accuracy of the early fire point. According to the image contour information of the aerosol plume and / or CO2 high value area, the fire area is estimated. Combined with the aerosol plume and / or CO2 high value area image, time series analysis is performed to warn the development trend of the fire. The horizontal expansion direction of the plume is usually consistent with the wind direction at the fire site. By observing the plume morphology and flow direction through continuous scanning cycles, the direction and path of fire spread can be determined.

[0071] It is worth noting that in the process of fire detection, smoke and CO2 gas produced by burning substances are important characteristic parameters. If aerosol plumes and CO2 high-value areas exist at the same location in a continuous scanning period, the interference of particles such as clouds and fog can be eliminated, and the influence of carbon sources such as vegetation can also be eliminated.

[0072] The fire alarm module automatically warns and notifies fire prevention personnel of fire information, including the specific location of the early fire point, the area of ​​the fire, the development trend and other information, so as to facilitate the next step of emergency response.

[0073] It can be seen from the above embodiments that aerosol particles and CO2 gas remote sensing detection is performed by aerosol lidar and CO2 lidar to identify aerosol plumes and CO2 high-value areas in the atmosphere. If aerosol plumes and CO2 high-value areas exist at the same position at the same time within a continuous scanning cycle, the interference of aerosol particles such as clouds and fog can be eliminated, and the influence of carbon sources such as vegetation can also be eliminated, thereby improving the accuracy of early fire point positioning and accelerating fire response.

[0074] It should be understood that the specific embodiments described herein are only used to explain the application, rather than to limit it. Based on the embodiments provided in this application, all other embodiments obtained by ordinary technicians in this field without creative work are within the protection scope of this application.

[0075] Obviously, the drawings are only some examples or embodiments of the present application. For ordinary technicians in the field, the present application can also be applied to other similar situations based on these drawings without creative work. In addition, it is understandable that although the work done in this development process may be complicated and lengthy, for ordinary technicians in the field, certain changes in design, manufacturing or production based on the technical content disclosed in this application are only conventional technical means and should not be regarded as insufficient content disclosed in this application.

Claims

1. A remote sensing detection method for early fire points, characterized in that: include: Controlling an aerosol laser radar to scan a target area, determining the spatiotemporal distribution of aerosols in the target area according to scanning data of the aerosol laser radar, and judging whether there is an aerosol plume in the target area according to the spatiotemporal distribution of aerosols; When an aerosol plume exists in the target area, the CO2 laser radar is controlled to detect the CO2 concentration in the scanning area where the aerosol plume is located, a single or multiple concentration profiles are obtained by the CO2 laser radar, the CO2 concentration distribution is determined according to the concentration profiles, and whether there is a high CO2 value area in the area where the aerosol plume is located or in the vicinity is determined according to the CO2 concentration distribution; When the CO2 high value area exists in the area where the aerosol plume is located or in the vicinity, the location of the fire is determined based on the area where the aerosol plume and / or the CO2 high value area are located.

2. The remote sensing detection method for early fire points according to claim 1 is characterized in that: The CO2 high value area is an area where the CO2 concentration is higher than other areas in the area where the aerosol plume is located or adjacent to the area.

3. The remote sensing detection method for early fire points according to claim 1 is characterized in that: When there is a high CO2 value area in the area where the aerosol plume is located or in the vicinity, the diffusion direction and diffusion path of the fire are also determined according to the shape and flow direction of the aerosol plume and / or the high CO2 value area.

4. The remote sensing detection method for early fire points according to claim 1 is characterized in that: When there is a high CO2 value area in the area where the aerosol plume is located or in the vicinity, the fire occurrence area is also determined according to the size of the aerosol plume and / or the high CO2 value area.

5. The remote sensing detection method for early fire points according to claim 1 is characterized in that: When there is a high CO2 value area in the area where the aerosol plume is located or in the vicinity, the trend of the fire situation is also determined based on changes in the aerosol plume and / or the high CO2 value area.

6. The remote sensing detection method for early fire points according to claim 1 is characterized in that: The scanning data of the aerosol laser radar includes optical parameters of aerosol particles, and the optical parameters include a distance correction signal, an extinction coefficient, a depolarization ratio and a backscattering coefficient.

7. The remote sensing detection method for early fire points according to claim 1 is characterized in that: The CO2 laser radar is a differential absorption CO2 laser radar, which emits two or more laser beams of a resonant wavelength and a non-resonant wavelength of CO2 during scanning; The scanning data of the CO2 laser radar includes the echo signal intensity, the echo signal intensity difference and the distance concentration distribution.

8. The remote sensing detection method for early fire points according to claim 1 is characterized in that: When there is a high CO2 value area in the area where the aerosol plume is located or in the vicinity, a fire alarm is sent and the location of the fire is displayed.

9. A remote sensing detection device for early fire points, characterized in that: include: A first detection module is used to control the aerosol laser radar to scan the target area, and obtain the aerosol spatiotemporal distribution data of the target area from the aerosol laser radar, and determine whether there is an aerosol plume in the target area based on the aerosol spatiotemporal distribution data of the target area; The second detection module is used for, when there is an aerosol plume in the target area, controlling the CO2 laser radar to detect the CO2 concentration in the scanning area where the aerosol plume is located, obtaining a single or multiple concentration profiles through the CO2 laser radar, determining the CO2 concentration distribution according to the concentration profiles, and judging whether there is a CO2 high value area in the area where the aerosol plume is located or in the vicinity according to the CO2 concentration distribution; The location determination module is used to determine the location of the fire according to the area where the aerosol plume and / or the CO2 high value area are located when the CO2 high value area exists in the area where the aerosol plume is located or in the vicinity.

10. A data processing terminal, comprising a memory and a processor, characterized in that: A computer program is stored in the memory, and the processor is configured to run the computer program to execute the remote sensing detection method for early-stage fire points according to any one of claims 1 to 7.

11. A remote sensing detection system for early fire points, characterized in that: comprising a remote sensing detection device and a data processing terminal as claimed in claim 10; The remote sensing detection device includes at least one aerosol laser radar and at least one CO2 laser radar; Alternatively, the remote sensing detection device includes a single or multiple CO2 laser radars with aerosol detection function.

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