Geological disaster monitoring method and device, electronic equipment and storage medium

Abstract

The application provides a geological disaster monitoring method, a geological disaster monitoring device, an electronic device and a computer readable storage medium. The method comprises: observing the ground surface beside the track through a synthetic aperture radar arranged on a train to obtain an observation image; obtaining deformation information of the ground surface according to the observation image; projecting the deformation information to a two-dimensional coordinate system, the two-dimensional coordinate system taking the spatial position of the synthetic aperture radar as the origin, taking the instantaneous driving direction of the train as the Y axis, and taking the direction horizontally pointing to the synthetic aperture radar and perpendicular to the instantaneous driving direction as the X axis; and monitoring the geological disaster distribution of the ground surface according to the deformation information in the two-dimensional coordinate system. According to the application, the synthetic aperture radar is carried on the train platform, more accurate observation can be realized, the deformation information is stored in the two-dimensional coordinate system, the data can be simplified, and the operation efficiency is improved.

Description

Technical Field

[0001] This invention relates to the field of geographic surveying and mapping technology, and in particular to a geological disaster monitoring method, a geological disaster monitoring device, an electronic device, and a computer-readable storage medium. Background Technology

[0002] The technology of using synthetic aperture radar (SAR) to observe surface deformation and thus monitor and prevent geological disasters is known. Existing SAR platforms are generally satellites. Satellite-based radar observations have many limitations, hindering accurate observation and precise geological disaster prevention. Some existing technologies involve monitoring devices on train platforms; however, these devices have not solved the problems of large data storage requirements and low computational efficiency. Summary of the Invention

[0003] Therefore, this application provides a geological disaster monitoring method, a geological disaster monitoring device, an electronic device, and a computer-readable storage medium, which can improve the accuracy of geological disaster monitoring while reducing data storage and simplifying calculations.

[0004] In one aspect, this application provides a geological disaster monitoring method, comprising: observing the ground surface beside the track using a synthetic aperture radar installed on a train to obtain observation images; obtaining deformation information of the ground surface based on the observation images; projecting the deformation information onto a two-dimensional coordinate system, wherein the two-dimensional coordinate system has the spatial position of the synthetic aperture radar as the origin, the instantaneous travel direction of the train as the Y-axis, and the direction horizontally pointing towards the synthetic aperture radar and perpendicular to the instantaneous travel direction as the X-axis; and monitoring the distribution of geological disasters on the ground surface based on the deformation information in the two-dimensional coordinate system.

[0005] According to a particular embodiment of this application, the ground surface beside the track is observed by a synthetic aperture radar installed on the train to obtain observation images, including: multiple observations of the ground surface by the synthetic aperture radar to obtain multiple observation images; and acquiring an optical image corresponding to the observation image by an optical camera during each observation by the synthetic aperture radar.

[0006] According to a particular embodiment of this application, obtaining surface deformation information based on observation images includes: using optical images to perform coarse registration of multiple observation images; and based on the coarse registration, performing fine registration of multiple observation images.

[0007] According to a particular embodiment of this application, coarse registration of multiple observation images is performed using optical images, including: selecting corresponding points from two optical images that correspond to two observation images in the multiple observation images; calculating the relative offset between the two optical images based on the corresponding points; and performing coarse registration of the two observation images based on the relative offset.

[0008] According to a particular embodiment of this application, the surface of the land beside the track is observed by a synthetic aperture radar installed on the train to obtain observation images, including: observing the surface of the land by using the strip mode of the synthetic aperture radar and marking potential geological hazard areas.

[0009] According to a particular embodiment of this application, the ground surface beside the track is observed by a synthetic aperture radar installed on the train to obtain observation images, including: observing potential hazard areas on the ground surface by using the focused mode of the synthetic aperture radar.

[0010] According to a specific embodiment of this application, multiple trains pass over the ground surface. Each train is equipped with a synthetic aperture radar (SAR), and the SARs of the multiple trains form a communication network. The SARs on the trains are used to observe the ground surface beside the track, obtaining observation images. This includes: observing the ground surface using the SARs on the multiple trains to obtain observation images. Based on the observation images, deformation information of the ground surface is obtained, including: real-time processing of the observation images to obtain the deformation information of the ground surface.

[0011] On the other hand, this application provides a geological disaster monitoring device, comprising: an observation module for observing the ground surface beside the track using a synthetic aperture radar installed on a train to obtain observation images; a deformation module for obtaining deformation information of the ground surface based on the observation images; a projection module for projecting the deformation information onto a two-dimensional coordinate system, wherein the two-dimensional coordinate system has the spatial position of the synthetic aperture radar as the origin, the instantaneous travel direction of the train as the Y-axis, and the direction horizontally pointing towards the synthetic aperture radar and perpendicular to the instantaneous travel direction as the X-axis; and a monitoring module for monitoring the distribution of geological disasters on the ground surface based on the deformation information in the two-dimensional coordinate system.

[0012] On the other hand, this application provides an electronic device, including: a processor; a memory; and an application program, the application program being stored in the memory and configured to be executed by the processor, the application program including instructions for performing the methods described above.

[0013] In another aspect, this application provides a computer-readable storage medium storing a computer program for performing the above-described method.

[0014] According to the geological hazard monitoring method, geological hazard monitoring device, electronic equipment, and computer-readable storage medium of this application, by mounting synthetic aperture radar on a train, landslide hazards along the sides of the train track can be observed more effectively, thereby timely preventing the impact of geological hazards on the railway track. Furthermore, by projecting the deformation information observed by synthetic aperture radar onto a two-dimensional coordinate system, one dimension of data can be reduced, simplifying the data volume and improving computational and storage efficiency. Attached Figure Description

[0015] The specific embodiments of this application are described in detail below with reference to the accompanying drawings, wherein:

[0016] Figure 1 A schematic flowchart of a geological disaster monitoring method according to an embodiment of this application is shown;

[0017] Figure 2 Showing according to Figure 1 A schematic diagram of the observation mode in the embodiment;

[0018] Figure 3 Showing according to Figure 1 A schematic diagram of the deformation projection of the embodiment;

[0019] Figure 4 A schematic diagram of the structure of a geological disaster monitoring device according to an embodiment of this application is shown;

[0020] Figure 5 A schematic diagram of the structure of an electronic device according to an embodiment of this application is shown. Detailed Implementation

[0021] To enable those skilled in the art to more clearly understand the concepts and ideas of this application, the application is described in detail below with reference to specific embodiments. It should be understood that the embodiments given herein are only a part of all possible embodiments of this application. After reading the specification of this application, those skilled in the art are capable of making improvements, modifications, or substitutions to parts or the entirety of the following embodiments, and such improvements, modifications, or substitutions are also included within the scope of protection claimed in this application.

[0022] In this document, the terms "one," "an," and other similar words are not intended to indicate that only one of the described things exists, but rather that the description refers only to one of the described things, which may have one or more. In this document, the terms "comprising," "including," and other similar words are intended to indicate a logical relationship, not a spatial relationship. For example, "A includes B" means that logically B belongs to A, not that spatially B is located inside A. Furthermore, the meanings of the terms "comprising," "including," and other similar words should be considered open-ended, not closed-ended. For example, "A includes B" means that B belongs to A, but B does not necessarily constitute all of A; A may also include other elements such as C, D, and E.

[0023] In this document, the terms "first," "second," and other similar terms are not intended to imply any order, quantity, or importance, but are merely used to distinguish different elements. In this document, the terms "embodiment," "this embodiment," "an embodiment," or "an example" do not indicate that the description applies only to one specific embodiment, but rather that such description may also be applicable to one or more other embodiments. Those skilled in the art will understand that any description made herein with respect to one embodiment can be substituted, combined, or otherwise combined with the descriptions in one or more other embodiments, and the new embodiments resulting from such substitutions, combinations, or other combinations are readily conceived by those skilled in the art and fall within the scope of protection of this application.

[0024] In the embodiments of this application, geological disasters can refer to geological processes or phenomena that are formed under the influence of natural or human factors, causing losses to human life and property and damaging the environment. The distribution and variation patterns of geological disasters in time and space are subject to both the natural environment and human activities, and are often the result of the interaction between humans and nature. In the embodiments of this application, geological disasters include landslides, collapses, landslides, and debris flows.

[0025] Natural disasters are diverse, with landslides, collapses, and debris flows occurring frequently. With the increasing number of railway projects under construction, the geological conditions involved in railways are becoming increasingly complex. Especially in areas with harsh geological conditions and significant terrain variations, railway transportation safety is severely threatened by natural geological disasters.

[0026] Landslides are a common natural geological hazard. A landslide occurs when rock masses, under the influence of water and gravity, slide down a slope along a certain sliding surface. Due to their enormous potential energy and speed, landslides often possess immense destructive power. Because of the nature of railway transportation, landslides can endanger people's lives. With the impact of extreme weather conditions brought about by global climate change, the threat of geological disasters along railway lines and the resulting economic losses will increase year by year. Furthermore, with the construction and long-term operation of urban lifeline projects such as subways, factors such as the deformation of underground passages also pose potential threats to the operation of these urban lifelines. Therefore, corresponding disaster monitoring, forecasting, and early warning are particularly important.

[0027] Synthetic Aperture Radar (SAR), due to its all-weather, all-time, and penetrating characteristics, is widely used for observing natural disasters on the Earth's surface. Interferometric Synthetic Aperture Radar (InSAR), developed in recent years, can achieve precise measurements of surface deformation, making it possible to monitor slow, long-term changes before landslides occur. Monitoring the movement of landslide bodies can provide early warnings of landslide disasters. Satellite SAR imagery is the primary data source for InSAR. Satellites repeatedly observe the same area with minimal viewing angle differences, and interferometric differential analysis is performed using two or more SAR images to remove error phase and topographic phase information, thus obtaining surface deformation information. While spaceborne SAR can achieve large-scale and efficient geological disaster monitoring, it still cannot meet practical needs for monitoring individual landslides. Its main problems are as follows:

[0028] 1. Long satellite revisit cycle. Due to the orbital nature of the satellite, the time interval between repeated observations of the same area is relatively long, while the development cycle of geological disasters is short. Especially under the influence of strong external factors such as rainstorms, floods, and earthquakes, the situation changes rapidly. Satellite remote sensing cannot capture the sliding signals of landslide bodies in a timely manner, resulting in a slow early warning response to disasters.

[0029] 2. Geometric Limitations of SAR Imagery. Most SAR data in this field has low resolution, making it difficult to accurately characterize individual landslides. High-resolution spaceborne SAR imagery is scarce. Train platforms, however, are close to the imaging target, acquiring images with high resolution and signal-to-noise ratio. Furthermore, the top-down, oblique imaging method of spaceborne SAR results in overlapping, inverted top and bottom, and shadowing characteristics, potentially obscuring landslides and increasing the difficulty of image interpretation. Additionally, residual phase from the terrain in high-slope areas can cause unwrapping errors during data processing. Railway platforms effectively avoid the complex representation relationships of traditional spaceborne SAR. By using the train platform as a carrier and its forward and perpendicular directions as axes, a simple coordinate system can be formed. Then, depending on the observation area along the railway line, corresponding observation directions can be set, enabling imaging based on train platform SAR sensors. This provides more direct and convenient observation of landslides along railway lines. Moreover, because this coordinate system is more sensitive to deformation information along the railway line and less affected by distortion, it avoids the various problems faced by spaceborne SAR.

[0030] 3. Difficulty in SAR image registration. Due to the complex terrain along the railway line, spaceborne SAR images face complex geometric distortions, which poses many challenges to SAR image registration. Furthermore, the presence of geometric distortions, especially overlay and shadows, can cause some areas to be missed, making effective observation impossible and potentially leading to the omission of potential geological hazards and causing irreparable economic losses.

[0031] 4. Decoratability factors and atmospheric effects. Spaceborne InSAR is affected by temporal decoherence, baseline decoherence, thermal noise decoherence, registration decoherence, and volume scattering decoherence factors, which reduce the coherence between images. At the same time, atmospheric effects can cause errors in the detection results.

[0032] Based on the characteristics of the application scenarios, the embodiments of this application propose an interferometric SAR method and device for monitoring landslide disasters along railway lines based on a high-speed train platform. The antenna is mounted on the outside of the high-speed train carriage, and images of landslide-prone areas are captured each time the train passes through. The images are then processed using the InSAR method to achieve high-precision, real-time, and low-cost landslide disaster monitoring.

[0033] The main advantages of the embodiments of this application are as follows:

[0034] 1. Platform Advantages: Compared to satellite platforms, train platforms are easier to operate, more scalable, and lower in cost. The SAR baseline on train platforms is more stable and has better coherence than airborne SAR. While satellite revisit cycles typically take several days, the revisit cycle on train platforms is related to the train's passing interval, allowing for repeated observations as short as a few minutes. Furthermore, the sensor distance from the study area significantly improves temporal resolution and signal-to-noise ratio. Satellite communication power is limited by signal attenuation and loss during long-distance transmission, while train platforms require less energy, are lighter and smaller, easier to operate, and have lower costs. Their power is unrestricted, the platform is highly scalable, and subsequent system debugging and maintenance are simple. Due to the large space available on train platforms, radar sensor antenna arrays can be deployed on the outside of the carriages, enabling high-resolution or even stereo imaging.

[0035] The installation of auxiliary equipment such as synchronous cameras can greatly enrich the platform information and provide high-precision auxiliary information for subsequent SAR image registration.

[0036] 2. Geometric Advantages: Train platforms offer superior deformation sensitivity and directional accuracy. The imaging geometry of train platform SAR provides an inherent advantage for observing geological hazards such as landslides in surrounding mountainous areas, making its disaster monitoring more targeted. Satellites have fixed orbits and incident angles, making them highly susceptible to topographical influences in areas with significant elevation differences. This can lead to line-of-sight obstruction and inverted top-to-bottom images, hindering image analysis and interpretation. Furthermore, a single orbit cannot comprehensively and effectively cover and detect geological hazards, and some areas lack necessary satellite data. In contrast, train platform-based SAR sensors offer a more flexible and variable observation range, avoiding the disadvantages of satellite platforms. Their bottom-up illumination capability can comprehensively cover geological hazards, and in elevated plains, they can also observe areas under bridges. Therefore, their ability to monitor and capture potential geological hazards is stronger and more reliable. In addition, the high-resolution SAR data obtained from train platforms is more conducive to small-area deformation detection, providing more reliable information and valuable time for disaster identification and early warning, striving to nip related disasters in the bud.

[0037] 3. Data Processing Advantages: In terms of data processing, spaceborne SAR is subject to varying degrees of atmospheric interference, affecting the analysis of interferometric phases. Interferometric SAR based on a train platform, however, is much closer to the observed object, making atmospheric interference negligible. When the spatial positions of the imaging sensors coincide, zero-baseline interferometry can be achieved, avoiding the involvement of external elevation data and reducing processing errors caused by the DEM (Digital Elevation Model). Simultaneously, data can be processed in real-time upon reception, improving data analysis efficiency. SAR data registration accuracy is higher with the aid of external camera data, significantly reducing errors caused by platform instability and compensating for weak GNSS (Global Navigation Satellite System) signals in mountainous, canyon, and tunnel areas, providing high-precision auxiliary data support for SAR data registration. The results can be projected using two-dimensional plane coordinates based on the train track, simplifying the algorithm and improving efficiency. Furthermore, the train platform can be equipped with a high-performance processor, enabling real-time SAR data processing and providing timely support for safe train operation.

[0038] 4. Advantages of working bands: Different bands have different polarization characteristics, different sensitivities to the same ground features, and different penetration capabilities to ground features such as vegetation on the surface of landslide bodies. Multi-band synchronous observation can achieve accurate atmospheric compensation, obtain multi-faceted and multi-level ground feature information, and improve the reliability of the results.

[0039] Figure 1 A schematic flowchart of a geological disaster monitoring method according to an embodiment of this application is shown.

[0040] According to this embodiment, the geological disaster monitoring method includes:

[0041] S110: The synthetic aperture radar installed on the train is used to observe the ground surface beside the track and obtain observation images.

[0042] In this embodiment, "train" can refer to a trainset, including railway trains and road trains. Railway trains include regular trains, subways, light rail, etc., while road trains include car trainsets, car trainsets, and road car units. The ground surface beside the track can refer to the ground, slopes, hillsides, rock formations, vegetation, etc., on both sides of the track.

[0043] Synthetic Aperture Radar (SAR) refers to a radar system that uses the relative motion between the radar and the target to synthesize a larger equivalent antenna aperture from a smaller actual antenna aperture through data processing. For example, SAR can be a radar system that uses a small antenna to move at a constant speed along the trajectory of a long linear array and radiate coherent signals. The echoes received at different locations are then coherently processed to obtain a higher resolution imaging radar. SAR can be divided into two categories: focused and unfocused.

[0044] Synthetic Aperture Radar (SAR) can be mounted on the train in a conformal manner (i.e., without altering the train's aerodynamic shape). The SAR data acquisition platform is mounted on the top or side of the high-speed train, and the antenna direction can be adjusted according to the relative position between the train and the landslide. The SAR sensor's outer envelope is conformally designed, not affecting the train's aerodynamic shape. The data receiving and processing platform is located inside the high-speed train, transmitting the results to the control center. The control center will then perform parameter control on the train's radar array.

[0045] The process of SAR data imaging processing can involve taking the echo signals acquired by high-speed trains, selecting an appropriate focusing algorithm for imaging processing based on different data acquisition modes, train platform speeds, and SAR sensor settings, to obtain a Single Look Complex (SLC) image, which facilitates subsequent registration and interferometry processing. Simultaneously, by utilizing network observations of different trains frequently traveling on the railway line, and leveraging a high-speed data transmission network, real-time or near-real-time processing can be performed on the train platform.

[0046] Synthetic Aperture Radar (SAR) can employ multiple modes for surface observation and image acquisition, and these modes can be switched adaptively. For example, SAR can use strip mode to observe the surface and mark areas with potential geological hazards; and SAR can use spotlight mode to observe hazardous areas on the surface.

[0047] Since the speed of the train platform is known and controllable, in order to further improve efficiency, a strip mode or other methods can be selected to conduct a rapid and efficient comprehensive survey of potential geological disaster areas along the railway. Then, based on this, for suspected disaster areas discovered in the previous survey, by rationally allocating train platform resources through different methods, high-resolution and high-frequency observations in modes such as clustering can be achieved, which can greatly improve the ability to accurately capture, monitor and warn of potential geological disasters along the railway.

[0048] When a high-speed train passes through a landslide hazard area at a constant speed, the SAR sensor is activated, with the antenna pointing towards one side of the landslide body. This invention adjusts the antenna angle according to the spatial distribution range and specific location of the landslide body, and can use imaging modes such as Stripmap and Spotlight to conduct low-resolution general surveys of disasters along railway lines and high-resolution detailed surveys of suspected landslide hazard areas, respectively. Figure 2 As shown, an adaptive observation mode is adopted. For large-area observation, the Stripmap mode is used, with the radar antenna pointing unchanged and the beam continuously sweeping across the slopes along the railway line to achieve wide-area mapping. After a potential hazard is detected, the area is marked. When passing through key geological hazard observation targets, the mode is switched to Spotlight mode. By adjusting the azimuth antenna beam pointing, the beam is always focused on a ground target area, continuously transmitting signals to the geological hazard body. The azimuth coherence time is increased, thus the synthetic aperture length is increased, achieving more refined observation. This meets the needs of rapid identification of potential geological hazards such as landslides along the railway line and their long-term changing patterns.

[0049] In this embodiment, multiple trains can pass over the Earth's surface. Each train is equipped with a synthetic aperture radar (SAR), and the SARs of these multiple trains form a communication network. At this time, the Earth's surface can be observed through the interconnected SARs on the multiple trains, obtaining observation images. These images can be processed in real time to obtain deformation information of the Earth's surface. Multiple interconnected SARs form an observation network, enabling networked observation.

[0050] The train platform relies on railway tracks and has good attitude stability. By relying on the high-frequency trains traveling on the railway line, multi-train network observation can be carried out to achieve high-frequency revisit of the target area. Utilizing high-speed data transmission networks and onboard high-computing power platforms, through optimized networking of different train platforms shuttling on the corresponding railway lines, near-real-time or real-time data processing can be carried out. This enables high-precision, high-frequency observation of key disaster-prone areas along the railway line, timely detection and early warning of corresponding disasters, and avoidance of serious train operation risks and disasters.

[0051] S120. Based on the observed images, obtain information on the deformation of the Earth's surface.

[0052] The specific methods for obtaining surface deformation information from observation images can include: SAR image registration, SAR data interferometry, extraction of high coherence points, phase unwrapping, atmospheric phase correction, and extraction of deformation results.

[0053] As an example, before image registration, multiple observations of the Earth's surface can be conducted using synthetic aperture radar (SAR) to obtain multiple observation images. During each SAR observation, an optical camera acquires the corresponding optical image. Optical cameras and other sensors can be synchronously installed on the train. Each time the SAR sensor is activated, an optical image is acquired. The GNSS signal and the image acquired by the synchronous camera provide high-precision external assistance for subsequent SAR image registration. Of course, when the optical camera is not needed (e.g., at night), it can be left off when the SAR is activated.

[0054] In this embodiment, an optical camera can refer to a shooting device that performs imaging based on optical principles (visible light, ultraviolet light, infrared light, etc.), and an optical image can refer to an image obtained by imaging based on optical principles.

[0055] Image registration can include coarse registration and fine registration. For example, optical images can be used to perform coarse registration on multiple observation images, and then fine registration can be performed on multiple observation images based on the coarse registration.

[0056] During coarse registration, corresponding points can be selected from two optical images that correspond to two observation images in multiple observation images. Then, based on the corresponding points, the relative offset between the two optical images can be calculated. Finally, based on the relative offset, coarse registration can be performed on the two observation images.

[0057] Corresponding points can refer to the image points formed by the same point on an objective object in different images. Coarse registration of two observed images based on relative offset can refer to using the relative offset as the initial value for coarse registration, correcting based on the relative offset after coarse registration, or directly using the relative offset as the result of coarse registration for the next step of fine registration.

[0058] The spatial positions of high-speed train tracks and sensors inevitably change slightly as the train moves, resulting in non-perfect overlap between images. This necessitates the registration of multiple SAR images. By setting up synchronized cameras, GNSS signals can be combined to assist in high-precision registration of SAR images. Furthermore, by reducing traditional registration calculations, computational efficiency can be effectively improved.

[0059] Because the imaging geometry of train imaging platforms is relatively simple, image offsets within a certain spatial range can generally be considered as existing in a one-dimensional offset direction. This simplifies the registration process. High-precision registration can be achieved using an auxiliary synchronous camera. Compared to the offsets caused by various complex factors in spaceborne SAR, high-speed train platform SAR is generally only affected by small-scale displacement information caused by external environmental factors such as locomotives and wind during operation. Therefore, methods such as thin plate splines are used for compensation processing in image registration and resampling. Registration is divided into two steps: coarse registration and fine registration using an auxiliary synchronous camera. The final registration accuracy must reach at least 1 / 8 pixel to avoid the impact of matching errors on coherence, thereby achieving better interferometric results.

[0060] Regarding coarse registration, image information acquired by a synchronous camera is used to extract the initial corresponding point information, and the positional differences are used to reflect the initial offset, providing initial values ​​for subsequent coarse registration. When there are many feature points, coarse registration based on SAR images can be omitted, and fine registration can be carried out directly based on the inversion offset of the synchronous camera. Coarse registration based on SAR images generally involves identifying corresponding points from two SAR images, calculating the relative offset between the images, and translating the images according to the pixel coordinate offset between the corresponding points. For mountainous terrain areas lacking man-made features, significant natural landform features are scarce, and the presence of speckle noise makes feature point selection difficult. Using synchronously acquired optical images, feature points are selected, and the registered SAR images are further corrected to improve registration accuracy.

[0061] For fine registration, based on coarse registration, control points are evenly distributed in the reference image. Sub-pixel precise positions of corresponding points are searched in the image to be registered according to the similarity rule. Coordinate transformation and pixel interpolation resampling are then performed on the image to be registered, using a thin-plate spline function for sampling, thus achieving fine registration. Fine registration typically employs the maximum correlation function method, calculating the cross-correlation coefficient R between the two images at different azimuth and range offsets. The position corresponding to the maximum value is the offset during registration. u and v represent the offsets in the range and azimuth directions, respectively. The registration result is achieved when R(u,v) is maximized, defined as follows:

[0062]

[0063] Regarding SAR data interferometry, each pair of primary and secondary images is multiplied by complex conjugate to form an interferogram. The phase difference component is the interferometric fringe pattern. The phase obtained from the initial synchronous interferometry is used as the topographic phase to compensate for the topographic phase in subsequent SAR data, resulting in a differential interferometric fringe pattern of the inverted surface deformation information for the corresponding region. The interferometric phase is composed of several parts from the following formula. Simultaneously, the interferometric fringe pattern is filtered and atmospheric phase corrected (generally small and negligible) to improve the signal-to-noise ratio of the interferometric phase pattern, thus obtaining a differential interferometric pattern reflecting the deformation of the target region, capable of reflecting a large-scale deformation in the study area.

[0064]

[0065] Regarding the extraction of high coherence points, differential interferometry is generally used for areas with rapid deformation. However, for areas prone to geological hazards with slow, long-term deformation, the image coherence is poor, making it difficult to effectively identify landslides, collapses, and other dynamic states. To reflect the subtle deformations related to geological hazards along railway lines, it is necessary to conduct time-series InSAR analysis based on corresponding high coherence points to capture potential small deformations related to geological hazards. The time-series InSAR method can utilize multiple train passing observations to obtain SAR data at different time phases. For multiple images, the amplitude deviation index is used to extract target points whose scattering characteristics remain stable over time. Surface deformation estimation is then performed based on these stable points. The calculation method was proposed by Ferretti in 2001, and the amplitude deviation index is expressed as follows:

[0066]

[0067] Regarding phase unwrapping, the phase values ​​in the interferometric phase map are wrapped between [-π, π]. It is necessary to restore them to their true values. Common unwrapping methods, such as minimum cost flow or 3D unwrapping, are generally used to ultimately restore the phase distortion of adjacent pixels. satisfy:

[0068]

[0069] Regarding atmospheric phase correction, under adverse weather conditions, the propagation path of radar signals is inevitably affected by atmospheric substances, thus requiring atmospheric phase removal. Atmospheric phase can be calculated using meteorological observation data of the study area, fitted with topographic information, or accurately estimated and removed using synchronous multi-band data.

[0070] Regarding the extraction of deformation results, after removing the influence of errors such as atmospheric phase, deformation information on the time series is obtained using methods such as least two-way or singular value decomposition (SVD).

[0071] S130. Project the deformation information onto a two-dimensional coordinate system. The two-dimensional coordinate system takes the spatial position of the synthetic aperture radar as the origin, the instantaneous direction of the train's travel as the Y-axis, and the direction that is horizontally pointing towards the synthetic aperture radar and perpendicular to the instantaneous direction of travel as the X-axis.

[0072] Before projection, geocoding is required, that is, firstly, the deformation monitoring results are geocoded from the SAR coordinate system to the geographic coordinate system. At this point, the deformation information is on the radar's line-of-sight (LOS) direction. To obtain the true deformation value, the deformation results need to be projected parallel to the actual landslide sliding direction, i.e., the direction of the maximum landslide slope. Let β be the angle between the LOS direction and the direction of the maximum slope, and α be the slope azimuth direction. Let θ be the slope angle, α be the incident angle, and α be the angle of inclination of the slope. s The angle between the high-speed train track direction and due north, with relevant spatial positions as follows: Figure 3 As shown.

[0073] Unit vector in the LOS direction and the unit vector in the direction of maximum slope It can be represented as:

[0074]

[0075]

[0076] The velocity vector in the LOS direction can then be expressed as:

[0077] v LOS =v E r E +v N r N +v Z r Z

[0078] Simultaneously satisfy:

[0079]

[0080] This can be further expressed as:

[0081]

[0082] The above formula can be viewed as:

[0083] Ax = y

[0084] x = A -1 y

[0085] detA=v E r E +v N r N +v Z rZ

[0086] The projection formula is obtained through calculation:

[0087]

[0088]

[0089] The velocity projected onto the direction of maximum slope reflects the true landslide deformation characteristics. To further illustrate the impact of landslide movement on the railway, a custom planar geographic coordinate system is adopted, with the spatial location of the SAR sensor as the origin. The instantaneous travel direction of the high-speed train is taken as the X-axis, with the direction of travel being positive; the Y-axis is the direction pointing from the slope towards the train and perpendicular to the travel direction, with the direction pointing towards the train being positive. Therefore, only the X and Y components of the deformation vector are considered. The X-component of slope deformation is parallel to the train track, having a small impact on the safety of the high-speed train. The Y-component is perpendicular to the track, and its magnitude determines the degree of danger posed by the landslide deformation to the high-speed railway.

[0090] By establishing a unique coordinate system with the vehicle's orientation as the X-axis and the direction pointing towards the vehicle as the Y-axis, the coordinate system is simplified. Considering that the slope angle is perpendicular to the train's direction of travel, this simplifies the calculation of landslide movement, improves accuracy, simplifies the algorithm, reduces one dimension of information, and eliminates the need for lifting rails.

[0091] S140. Monitor the distribution of geological hazards on the Earth's surface based on deformation information in a two-dimensional coordinate system.

[0092] By transforming deformation information into a two-dimensional coordinate system, the storage and computation of deformation information can be simplified, enabling monitoring equipment and computing units to perform more effectively.

[0093] Figure 4 A schematic diagram of a geological disaster monitoring device according to an embodiment of this application is shown.

[0094] According to this embodiment, the geological disaster monitoring device 400 includes:

[0095] The observation module 410 is used to observe the ground surface beside the track using a synthetic aperture radar installed on the train, and obtain observation images.

[0096] Deformation module 420 is used to obtain surface deformation information based on observed images;

[0097] The projection module 430 is used to project deformation information onto a two-dimensional coordinate system. The two-dimensional coordinate system takes the spatial position of the synthetic aperture radar as the origin, the instantaneous direction of travel of the train as the Y-axis, and the direction that is horizontal to the track and perpendicular to the instantaneous direction of travel as the X-axis.

[0098] The monitoring module 440 is used to monitor the distribution of geological hazards on the earth's surface based on deformation information in a two-dimensional coordinate system.

[0099] In one embodiment, the observation module 410 is further configured to:

[0100] Multiple observation images were obtained by conducting multiple observations of the Earth's surface using synthetic aperture radar;

[0101] During each observation by synthetic aperture radar, an optical image corresponding to the observed image is acquired through an optical camera.

[0102] In one embodiment, the deformation module 420 is further configured to:

[0103] Using optical images, coarse registration is performed on multiple observation images;

[0104] Based on coarse registration, fine registration is performed on multiple observation images.

[0105] In one embodiment, the deformation module 420 is further configured to:

[0106] Select corresponding points from two optical images that correspond to two of the multiple observation images;

[0107] Calculate the relative offset between two optical images based on the corresponding points;

[0108] Based on the relative offset, coarse registration is performed on the two observation images.

[0109] In one embodiment, the observation module 410 is further configured to:

[0110] The surface is observed using the strip mode of synthetic aperture radar, and potential geological hazard areas are marked.

[0111] In one embodiment, the observation module 410 is further configured to:

[0112] The focus mode of synthetic aperture radar is used to observe potential hazard areas on the ground.

[0113] In one embodiment, multiple trains pass over the surface, each of which is equipped with a synthetic aperture radar, and the observation module 410 is further configured to:

[0114] The ground surface is observed and images are obtained by using synthetic aperture radars that communicate with each other and are installed on multiple trains.

[0115] The following combination Figure 5 This application describes an electronic device according to an embodiment of the present application.

[0116] like Figure 5As shown, the electronic device 500 includes one or more processors 510 and memory 520.

[0117] The processor 510 may be a central processing unit (CPU) or other form of processing unit with data processing capabilities and / or instruction execution capabilities, and may control other components in the electronic device 500 to perform desired functions.

[0118] The memory 520 may include one or more computer program products, which may include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory may include, for example, random access memory (RAM) and / or cache memory. The non-volatile memory may include, for example, read-only memory (ROM), hard disk, flash memory, etc. One or more computer program instructions may be stored on the computer-readable storage medium, and the processor 510 may execute the program instructions to implement the geological disaster monitoring methods of the various embodiments of this application described above, and / or other desired functions.

[0119] In one example, the electronic device 500 may also include an input device 530 and an output device 540, which are interconnected via a bus system and / or other forms of connection mechanism (not shown).

[0120] For example, the input device 530 may be a microphone or microphone array for capturing voice input signals; it may be a communication network connector for receiving the collected input signals from the cloud or other devices; and it may also include, for example, a keyboard, mouse, etc.

[0121] The output device 540 can output various information to the outside, including determined distance information, direction information, etc. The output device 540 may include, for example, a display, a speaker, a printer, and a communication network and its connected remote output devices, etc.

[0122] Of course, for the sake of simplicity, Figure 5 Only some of the components of the electronic device 500 relevant to this application are shown in this illustration; components such as buses, input / output interfaces, etc., are omitted. In addition, the electronic device 500 may include any other suitable components depending on the specific application.

[0123] Embodiments of this application may also be computer-readable storage media storing computer program instructions thereon, which, when executed by a processor, cause the processor to perform the steps in the geological disaster monitoring methods according to various embodiments of this application described above.

[0124] The computer-readable storage medium may be any combination of one or more readable media. A readable medium may be a readable signal medium or a readable storage medium. A readable storage medium may, for example, include, but is not limited to, electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatuses, or devices, or any combination thereof. More specific examples of readable storage media (a non-exhaustive list) include: electrical connections having one or more wires, portable disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fibers, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof.

[0125] The concepts, principles, and ideas of this application have been described in detail above with reference to specific embodiments (including examples and instances). Those skilled in the art should understand that the embodiments of this application are not limited to those given above. After reading this application, those skilled in the art can make any possible improvements, substitutions, and equivalents to the steps, methods, apparatus, and components in the above embodiments, and such improvements, substitutions, and equivalents should be considered to fall within the scope of this application. The scope of protection of this application is limited to the claims.

Claims

1. A method for monitoring geological hazards, comprising: The synthetic aperture radar installed on the train is used to observe the ground surface beside the track and obtain observation images. The observation of the ground surface beside the track using synthetic aperture radar installed on the train, to obtain observation images, includes: Multiple observation images were obtained by repeatedly observing the surface using the synthetic aperture radar. During each observation by the synthetic aperture radar, an optical image corresponding to the observed image is acquired by an optical camera; Based on the observed images, the deformation information of the land surface is obtained; The step of obtaining the deformation information of the land surface based on the observed image includes: The optical images are used to perform coarse registration of the multiple observation images; The coarse registration of the multiple observation images using the optical images includes: Select corresponding points from two optical images that correspond to two of the multiple observation images; Calculate the relative offset between the two optical images based on the corresponding points; Based on the relative offset, the two observed images are coarsely registered; Based on the coarse registration, fine registration is performed on the multiple observation images; The deformation information is projected onto a two-dimensional coordinate system, with the spatial position of the synthetic aperture radar as the origin, the instantaneous travel direction of the train as the Y-axis, and the direction pointing horizontally to the synthetic aperture radar and perpendicular to the instantaneous travel direction as the X-axis. Based on the deformation information in the two-dimensional coordinate system, the distribution of geological hazards on the land surface is monitored.

2. The geological disaster monitoring method according to claim 1, wherein, The observation of the ground surface beside the track using synthetic aperture radar installed on the train, to obtain observation images, includes: The surface is observed using the strip mode of the synthetic aperture radar, and potential geological hazard areas are marked.

3. The geological disaster monitoring method according to claim 2, wherein, The observation of the ground surface beside the track using synthetic aperture radar installed on the train, to obtain observation images, includes: The potential hazard areas on the ground surface are observed using the focused beam mode of the synthetic aperture radar.

4. The geological disaster monitoring method according to claim 1, wherein, Multiple trains pass over the aforementioned surface. Each of these trains is equipped with a synthetic aperture radar (SAR), and the SARs of these trains form a communication network. The SARs on the trains are used to observe the surface beside the track, obtaining observation images, including: The surface was observed using synthetic aperture radar installed on the multiple trains to obtain observation images; The step of obtaining the deformation information of the land surface based on the observed image includes: The observed images are processed in real time to obtain deformation information of the land surface.

5. A geological disaster monitoring device, comprising: The observation module is used to observe the ground surface beside the track using a synthetic aperture radar installed on the train, and obtain observation images. The observation of the ground surface beside the track using synthetic aperture radar installed on the train, to obtain observation images, includes: Multiple observation images were obtained by repeatedly observing the surface using the synthetic aperture radar. During each observation by the synthetic aperture radar, an optical image corresponding to the observed image is acquired by an optical camera; A deformation module is used to obtain deformation information of the land surface based on the observed image; obtaining the deformation information of the land surface based on the observed image includes: The optical images are used to perform coarse registration of the multiple observation images; The coarse registration of the multiple observation images using the optical images includes: Select corresponding points from two optical images that correspond to two of the multiple observation images; Calculate the relative offset between the two optical images based on the corresponding points; Based on the relative offset, the two observed images are coarsely registered; Based on the coarse registration, fine registration is performed on the multiple observation images; The projection module is used to project the deformation information onto a two-dimensional coordinate system, wherein the two-dimensional coordinate system takes the spatial position of the synthetic aperture radar as the origin, the instantaneous travel direction of the train as the Y-axis, and the direction that is horizontal to the synthetic aperture radar and perpendicular to the instantaneous travel direction as the X-axis. The monitoring module is used to monitor the distribution of geological hazards on the land surface based on the deformation information in the two-dimensional coordinate system.

6. An electronic device, comprising: processor; Memory; An application, stored in the memory and configured to be executed by the processor, the application including instructions for performing the geological hazard monitoring method according to any one of claims 1 to 4.

7. A computer-readable storage medium storing a computer program for performing the geological hazard monitoring method according to any one of claims 1 to 4.

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