Four-corner-point-based visualization processing method and system for web-side sar field of view projection

Abstract

The application provides a kind of four corner point-based Web SAR field of view projection visualization processing method and system, it is related to satellite task visualization field, this method includes: determining the start angle and span angle of sector angle domain;Discrete equidistant to azimuth, spherical positive solution is carried out to each discrete azimuth, and polygon entity is generated;With the space position of the platform where SAR load is located as vertex, with each vertex of ground projection polygon as bottom edge vertex, beam cone is constructed.The application realizes the spherical sector construction of SAR field of view and the generation of ground projection in browser end by the data driven mode of center point and four corner points, accurately restores the boundary of field of view with less input parameters;Through azimuth sorting and angle domain normalization, the continuity and closure of projection topology are guaranteed;Through the construction of beam cone, the direction and opening angle of field of view are intuitively presented, and the intuitive and interactive display of SAR field of view space range and azimuth direction is realized.

Description

A Visualization Method and System for Web-based SAR Field-of-View Projection Based on Four Corner Points Technical Field

[0001] This application relates to the field of satellite mission visualization technology, specifically to a visualization processing method and system based on web-based SAR field-of-view projection using four corner points. Background Technology

[0002] Currently, the field-of-view modeling and simulation visualization of Synthetic Aperture Radar (SAR) satellite missions mainly rely on two types of tools: commercial software represented by STK (Satellite Tool Kit) and self-developed engines based on client-side graphics libraries (such as OpenGL and Direct3D). The former provides mature sensor modeling and visualization capabilities, supporting field-of-view analysis, coverage calculation, and orbit simulation of SAR payloads. It can dynamically generate the visual effect of sensor frustums by configuring parameters such as field of view angle, satellite latitude and longitude, and attitude. The latter achieves more flexible rendering control through a low-level graphics interface, which can meet the needs of mission simulation scenarios with high real-time or customization requirements.

[0003] However, both of the above solutions are based on a client / server architecture. This architecture requires the client to install a separate program, resulting in strong system dependencies, poor cross-platform compatibility, and high upgrade and maintenance costs. In contrast, a browser / server architecture (B / S architecture) does not require client installation and can be accessed directly through a browser. Web-based 3D visualization solutions can run across platforms such as Windows, Linux, macOS, and mobile terminals, and are easily integrated with systems for task planning, command and control, and other applications.

[0004] In the B / S architecture, Web 3D engines such as Cesium provide a basic framework for Earth visualization. However, their built-in coordinate and geometric models are mainly geared towards optical fields of view or objects that fit the ground surface. They lack visualization support for the unique beam characteristics of SAR sensors. In most cases, fan-shaped and cone-shaped projections are used to replace SAR field of view fan-shaped projections and beam cones. However, this does not vividly reflect the characteristics of SAR payload projection. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this application provides a visualization processing method and system for web-based SAR field-of-view projection based on four corner points, which solves the problems of complex deployment, insufficient cross-platform capability, and poor scalability of existing C / S architecture in SAR mission situation visualization.

[0006] To achieve the above objectives, this application provides the following technical solution:

[0007] In a first aspect, embodiments of this application provide a visualization processing method for Web-based SAR field-of-view projection based on four corner points. This visualization processing method for Web-based SAR field-of-view projection based on four corner points includes: obtaining the latitude, longitude, and elevation coordinates of the satellite's center point, and the latitude, longitude, and elevation coordinates of the four corner points of the SAR payload's field of view on the Earth's surface; using the center point as the reference origin, calculating the azimuth angle and spherical geodesic distance of the four corner points relative to the center point to determine the starting angle and spanning angle of the sector angle domain; discretizing the azimuth angle at equal intervals according to a preset number of segments within the sector angle domain, performing spherical forward solutions on each discrete azimuth angle with the inner edge radius and outer edge radius respectively to obtain an inner arc point sequence and an outer arc point sequence; arranging the inner arc point sequence in descending order of azimuth and arranging the outer arc point sequence in ascending order of azimuth, splicing them together to form a closed set of vertices of a surface polygon, and appending the same vertex to the beginning and end of the closed set of vertices of the surface polygon to make the rendering closed;

[0008] The polygon vertices are converted from latitude, longitude, and height coordinates to 3D scene coordinates, generating polygonal entities that fit the ground reference surface. The point-by-point height mode is enabled to make the vertex elevation take effect point by point. The ground projection surface is generated in the browser-side 3D rendering engine, and the fill material and transparency parameters are set. Using the spatial position of the SAR payload platform as the vertex and each vertex of the ground projection polygon as the bottom edge vertex, a beam cone is formed by constructing triangular facets that connect end to end. Colors and semi-transparent materials are configured for the triangular facets to reflect the field of view direction and opening characteristics during display.

[0009] Secondly, embodiments of this application provide a visualization processing system for Web-based SAR field-of-view projection based on four corner points. This visualization processing system for Web-based SAR field-of-view projection based on four corner points includes: a coordinate acquisition module, a sector corner domain determination module, a sector corner domain analysis module, a projection processing module, and a display processing module.

[0010] Specifically, the coordinate acquisition module is used to acquire the latitude, longitude, and elevation coordinates of the satellite's center point, as well as the latitude, longitude, and elevation coordinates of the four corner points of the SAR payload's field of view on the Earth's surface; the sector angle domain determination module is used to calculate the azimuth angles and spherical geodesic distances of the four corner points relative to the center point, using the center point as the reference origin, to determine the starting angle and spanning angle of the sector angle domain; the sector angle domain analysis module is used to discretize the azimuth angles at equal intervals within the sector angle domain according to a preset number of segments, and to perform spherical forward solutions on each discrete azimuth angle using the inner and outer edge radii respectively, obtaining the inner arc point sequence and the outer arc point sequence. The inner arc point sequence is arranged in descending order of azimuth, and the outer arc point sequence is arranged in ascending order of azimuth, and then spliced ​​together to form a closed surface polygon. The vertex set is used to append the same vertex to the beginning and end of the closed surface polygon vertex set to close the rendering; the projection processing module is used to convert the polygon vertices from latitude, longitude and height coordinates to 3D scene coordinates, generate polygon entities that fit the surface reference surface, and enable the point-by-point height mode so that the vertex elevation takes effect point by point; the surface projection surface is generated in the browser-side 3D rendering engine and the fill material and transparency parameters are set; the display processing module is used to construct a beam cone by using the spatial position of the SAR payload platform as the vertex and each vertex of the surface projection polygon as the bottom edge vertex, and configure the color and semi-transparent material of the triangular facets to reflect the field of view direction and opening characteristics during the display process.

[0011] Thirdly, embodiments of this application provide an electronic device, which includes: a processor, a memory, and a program stored in the memory and executable on the processor. When the program is executed by the processor, it implements the visualization processing method for Web-based SAR field projection based on four corner points as described in the first aspect.

[0012] Fourthly, embodiments of this application provide a computer-readable storage medium storing a program or instructions that, when executed by a processor, implement the visualization processing method for Web-based SAR field-of-view projection based on four corner points as described in the first aspect.

[0013] This application provides a visualization processing method and system for web-based SAR field-of-view projection based on four corner points. Compared with existing technologies, it has the following advantages:

[0014] This application generates closed surface polygons that conform to the characteristics of the Earth's spherical surface by accurately acquiring the latitude, longitude, and altitude coordinates of the satellite center point and the four corner points of the SAR field of view, combined with spherical geometry calculations, azimuth discretization, and spherical forward solving algorithms. Furthermore, it generates polygonal entities that conform to the surface reference plane through coordinate transformation. A point-by-point height mode is enabled to ensure precise conformity between the polygonal entities and the actual terrain, guaranteeing the accuracy of the SAR field of view surface projection. By constructing a beam cone and configuring a semi-transparent material, the abstract SAR field of view coverage, field of view direction, and opening characteristics are transformed into intuitive and visible 3D graphics, lowering the barrier to understanding professional information. The technical solution of this application is fully compatible with browser-side 3D rendering engines, achieving efficient rendering and display on the web without the need for deploying professional offline software, improving the convenience and cross-scene applicability of SAR field of view visualization. Simultaneously, through standardized vertex stitching, triangular patch construction processes, and closed rendering design, the visualization processing logic is simplified, ensuring the stability of the rendering process, facilitating engineering implementation and subsequent maintenance, and providing technical support for remote sensing mission planning, payload performance verification, and other related work. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 is a flowchart illustrating a visualization method for Web-based SAR field-of-view projection based on four corner points, provided in an embodiment of this application.

[0017] Figure 2 is a schematic diagram of spherical interpolation sampling provided in an embodiment of this application;

[0018] Figure 3 is a schematic diagram of the structure of a web-based SAR field-of-view projection visualization system based on four corner points provided in an embodiment of this application;

[0019] Figure 4 is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention are described clearly and completely. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes the element.

[0022] This application provides a visualization processing method and system for SAR field-of-view projection based on four corner points on a web-based platform, which solves the problems of complex deployment, insufficient cross-platform capability, and poor scalability of existing C / S architectures in SAR mission situation visualization.

[0023] To better understand the above technical solutions, the following will provide a detailed explanation of the technical solutions in conjunction with the accompanying drawings and specific implementation methods.

[0024] The following section first introduces a visualization processing method for Web-based SAR field-of-view projection based on four corner points, provided in the embodiments of this application.

[0025] The flowchart of a visualization processing method for Web-based SAR field-of-view projection based on four corner points provided in this application embodiment is shown in Figure 1. The visualization processing method for Web-based SAR field-of-view projection based on four corner points may include the following steps S110-S150.

[0026] S110: Obtain the latitude, longitude, and elevation coordinates of the satellite's center point, as well as the latitude, longitude, and elevation coordinates of the four corner points of the SAR payload's field of view on the Earth's surface.

[0027] Understandably, this application provides basic data support for all subsequent geometric calculations by accurately obtaining the latitude, longitude, and altitude coordinates of the satellite's center point and the four corner points of the SAR payload's field of view, ensuring the accuracy of the data source for the entire visualization process. At the same time, this application directly uses the four corner points of the Earth's surface as input, eliminating the need for complex field of view boundary derivation, simplifying the data preparation process, and ensuring that the technical solution provided by this application has engineering applicability.

[0028] It should be noted that the latitude, longitude, and elevation coordinates of the satellite's center point, as well as the latitude, longitude, and elevation coordinates of the four corner points of the SAR payload's field of view on the Earth's surface, are in a combination of longitude, latitude, and elevation. The elevation is taken as either surface elevation or elevation of a specified reference surface. This allows for both accurate surface projection that closely matches the actual terrain and the standardized display requirements based on a reference surface under specific tasks, thereby improving the method's applicability in different remote sensing tasks and terrain scenarios. Furthermore, the standardized coordinate format of longitude, latitude, and elevation facilitates compatibility with the data formats of various geographic information systems and web-based 3D rendering engines, reducing the complexity of data exchange and conversion.

[0029] It should be noted that the aforementioned center point is the projection center of the field of view on the ground or the equivalent sub-satellite point. This ensures the spatial correspondence with the SAR payload's field of view and guarantees the accuracy of the benchmark for subsequent azimuth and spherical distance calculations. In practical engineering applications, an appropriate center point positioning method can be selected based on data acquisition conditions and computational efficiency requirements.

[0030] It should be noted that the four corner points are used to determine the left and right boundaries and the inner and outer boundaries according to the logical relationship of left outer, right outer, right inner, and left inner. When the order is not provided, the boundaries are automatically identified by azimuth sorting. Understandably, this application clearly defines the logical order of the four corner points to define the boundaries, providing clear rules for the use of corner points in subsequent steps such as determining the sector angle domain, splicing polygon vertices, and constructing the beam cone. At the same time, an automatic azimuth sorting mechanism is set up to automatically identify the boundaries when the corner point order is not provided, avoiding visualization errors caused by disordered corner point order.

[0031] S120. Using the center point as the reference origin, calculate the azimuth angle and spherical geodesic distance of the four corner points relative to the center point to determine the starting angle and spanning angle of the sector angle domain.

[0032] Understandably, this application uses a spherical geometry-based calculation method adapted to the characteristics of the Earth's curved surface. By using the center point of the satellite as the reference origin to calculate the azimuth angles and spherical geodesic distances of the four corner points, it can lock the fan-shaped coverage area of ​​the SAR field of view on the sphere. By determining the starting angle and the crossing angle, the boundary range of subsequent discrete calculations can be clearly defined.

[0033] S130. Discretize the azimuth angles at equal intervals within the sector angular domain according to a preset number of segments. Perform spherical forward solutions on each discrete azimuth angle using the inner edge radius and outer edge radius respectively to obtain the inner arc point sequence and the outer arc point sequence. Arrange the inner arc point sequence in descending order of azimuth and arrange the outer arc point sequence in ascending order of azimuth. Piece them together to form a closed set of vertices of a polygonal surface. Add the same vertex to the beginning and end of the closed set of vertices of a polygonal surface to make the rendering closed.

[0034] Understandably, this application uses equally spaced discrete azimuth angles to perform spherical forward solving, generating inner and outer arc point sequences to ensure the smoothness and uniformity of the surface projection boundary. Appending the same vertex to the beginning and end of the formed closed surface polygon vertex set ensures the polygon's closure during subsequent rendering, avoids rendering errors, and improves the integrity of the visualized graphics.

[0035] S140. Convert the polygon vertices from latitude, longitude, and height coordinates to 3D scene coordinates, generate a polygon entity that fits the ground reference surface, and enable the point-by-point height mode so that the vertex elevation takes effect point by point; generate the ground projection surface in the browser-side 3D rendering engine and set the fill material and transparency parameters.

[0036] Understandably, this application converts latitude, longitude, and elevation coordinates into 3D scene coordinates, realizing the mapping from geospatial data to rendering space; it enables point-by-point elevation mode so that vertex elevations take effect point by point, ensuring that the generated polygonal entities fit the actual terrain and realistically reflect the coverage of the SAR field of view in different terrain areas. Then, based on a browser-side 3D rendering engine, this application sets fill material and transparency parameters in the generated surface projection, which can distinguish between SAR field-covered and uncovered areas in the 3D scene, improving the intuitiveness and recognizability of the visualization results, while adapting to browser-side rendering engines to meet the lightweight display requirements of the web.

[0037] S150. Using the spatial location of the SAR payload platform as the vertex and each vertex of the surface projection polygon as the base vertex, construct a beam cone by connecting triangular facets end to end. Assign colors and semi-transparent materials to the triangular facets to reflect the field of view direction and aperture characteristics during display. When assigning colors to each triangular facet, a color consistent with or coordinated with the projection surface can be selected. It should be noted that the surface projection polygon is the polygon corresponding to the aforementioned set of closed surface polygon vertices.

[0038] Understandably, this application uses the spatial location of the SAR payload platform as the vertex and the vertices of the surface projection polygon as the base vertices. Triangular facets connected end to end can be constructed sequentially according to the polygon vertices and spliced ​​together to form a beam cone, which can simulate the spatial propagation path and three-dimensional shape of the SAR payload beam. By configuring colors and semi-transparent materials, the field of view direction and aperture characteristics can be intuitively represented, transforming abstract beam parameters into visual graphics. The four triangular facet structures connected end to end not only simplify the construction logic of the three-dimensional model but also ensure the integrity of the beam cone, facilitating efficient rendering on the Web and helping users quickly understand the spatial pointing relationship of the SAR field of view.

[0039] The above is a specific implementation of a web-based SAR field-of-view projection visualization method based on four corner points provided in this application. This application uses a data-driven approach that combines the center point and the four corner points to realize the spherical sector construction and surface projection generation of the SAR field of view on the browser side, which can accurately restore the field of view boundary with fewer input parameters; the continuity and closure of the projection topology are ensured by azimuth sorting and corner domain normalization; and the field of view direction and opening angle are intuitively presented by constructing a beam cone composed of four triangular facets, realizing an intuitive and interactive display of the spatial range and azimuth direction of the SAR field of view.

[0040] In some embodiments, the aforementioned calculation of the azimuth angles and spherical geodesic distances of the four corner points relative to the center point, using the center point as the reference origin, is used to determine the starting angle and spanning angle of the sector angle domain. Specifically, the aforementioned S120 may include the following steps:

[0041] S210. Using the center point as the reference origin, convert the coordinates of the center point and the four corner points into radians. It is understood that this application uniformly converts the coordinates of the center point and the four corner points into radians, providing a unified coordinate unit for subsequent calculations of spherical trigonometry formulas.

[0042] S220. The azimuth angle of each corner point relative to the center point is calculated using spherical trigonometry formulas. The spherical distance from the center point to each corner point is calculated using the semi-versus formula as the geodesic length calculation model. The azimuth angle is defined as 0° at true north and ranges from 0° to 360° in a clockwise direction. It is understood that this application uses spherical trigonometry formulas to calculate the azimuth angle and the semi-versus formula to calculate the spherical distance, fully adapting to the characteristics of the Earth's curved surface. Furthermore, this application clearly defines the rule of 0° at true north and 0°-360° in a clockwise direction for the azimuth angle, thus unifying the angle calculation standard.

[0043] S230. The corner points are sorted in descending order based on their spherical distances. The two corner points with the largest distance are defined as the outer edge point pair, and the average spherical distance of the outer edge point pair is calculated as the outer edge radius of the sector corner domain. The two corner points with the smallest distance are defined as the inner edge point pair, and the average spherical distance of the inner edge point pair is calculated as the inner edge radius of the sector corner domain. It is understood that this application categorizes and sorts the corner points based on their spherical distances and determines the inner and outer edge radii by taking the average value. This simplifies the definition logic of the sector corner domain boundary, balances the discreteness of the corner point data, and ensures that the sector boundary accurately covers the actual range of the SAR field of view.

[0044] S240. Analyze the azimuth information of the midpoints of the outer edge point pairs to determine the starting angle and spanning angle of the sector angle domain. It is understood that this application determines the starting angle and spanning angle by analyzing the azimuth of the outer edge point pairs, thereby locking the angle range of the sector angle domain and defining the boundary for subsequent azimuth discretization calculations.

[0045] S250. When the sector angle domain spans 0° or 360°, angle normalization is performed to maintain azimuth continuity. Understandably, this application performs angle normalization for special scenarios spanning 0° or 360°, solving the problem of azimuth continuity breakage, ensuring the integrity and continuity of the parameters of the entire sector angle domain, and ensuring that the boundaries of the subsequently generated surface projection polygons are closed and without logical breaks.

[0046] In some embodiments, the aforementioned analysis of the azimuth information of the outer edge point to the midpoint point determines the starting angle and spanning angle of the sector angle domain. Specifically, the aforementioned S240 may include the following steps:

[0047] S310. Extract the first azimuth and the second azimuth of the outer edge point pair in a clockwise direction, and calculate the azimuth difference between the first azimuth and the second azimuth in a clockwise direction.

[0048] S320. When the azimuth difference is less than or equal to 180°, determine that the starting angle of the sector is equal to the first azimuth, and the span angle of the sector is equal to the azimuth difference.

[0049] S330. When the azimuth difference is greater than 180°, determine that the starting angle of the sector is equal to the second azimuth, and the span angle of the sector is the difference between 360° and the azimuth difference.

[0050] In the embodiments of this application, it is understood that this application explicitly extracts the first and second azimuth angles of the outer edge point pairs in a clockwise direction and calculates the difference, thus unifying the directional standard for angle calculation. For conventional scenarios where the azimuth angle difference is less than or equal to 180°, this application explicitly uses the first azimuth angle as the starting angle and the azimuth angle difference as the crossing angle, thereby quickly determining the angle range of a conventional sector-shaped angular domain. For special scenarios where the azimuth angle difference is greater than 180°, the starting angle and crossing angle are defined in reverse to solve the angle calculation problem of the sector-shaped angular domain crossing the 360° boundary, avoiding the loss or redundancy of the sector-shaped area due to incorrect definition of the angle range. This application ensures, through scenario-based judgment, that regardless of the azimuth angle distribution of the outer edge point pairs, the sector-shaped angular domain that conforms to the actual coverage of the SAR field of view can be accurately determined.

[0051] In some embodiments, the coordinates of the center point are: The coordinates of any corner point are ,in, Indicates the first Longitude of each corner point Indicates the first The latitude of each corner point; .

[0052] The azimuth angle of each corner point relative to the center point satisfies the expression:

[0053]

[0054] in, It is the azimuth angle. Represents the arctangent function in the four quadrants. and It is an intermediate variable and satisfies the expression:

[0055]

[0056] In the formula, Due to the difference in longitude, and , Indicates the longitude of the center point. Indicates the latitude of the center point. Represents the sine function. This represents the cosine function.

[0057] In the embodiments of this application, it is understood that this application uses the principle of spherical trigonometry to transform latitude and longitude coordinates into relative azimuth relationships, and calculates the azimuth angle of each SAR field of view point relative to the center point of the satellite. Intermediate variables The east-west offset of the corner point relative to the center point is represented by the product of the sine of the longitude difference and the cosine of the latitude of the corner point; intermediate variable By combining the latitude cosine and sine values ​​of the center point and corner points, as well as the longitude difference cosine value, the influence of north-south offset on spherical curvature is comprehensively characterized. This application is approved. The function directly outputs the azimuth angle within the range of 0°-360° clockwise, with true north as 0°.

[0058] Based on this, the aforementioned azimuth formula is derived using spherical trigonometry, fully considering the influence of the Earth's curvature on direction and avoiding azimuth deviations in planar geometric calculations. The formula is constructed based on latitude and longitude coordinates, requiring only the latitude and longitude coordinates of the center point and corner points as input parameters, without the need for additional complex parameters. Furthermore, the formula consists of basic trigonometric functions and inverse trigonometric functions, without complex iterative calculations, and can be directly implemented in web-based rendering engines and geographic information systems through code, making it suitable for web-based visualization applications.

[0059] In some embodiments, the spherical distance from the aforementioned center point to each corner point satisfies the expression:

[0060]

[0061] In the formula, Represents spherical distance. This represents the average radius of the Earth.

[0062] In the embodiments of this application, it is understood that variables By using trigonometric functions to calculate the difference in latitude and longitude, the relative relationship between the latitude and longitude of two points is integrated, thus eliminating plane projection errors; variables The variable is converted using the arctangent function. Converted to the central angle in radians between two points; through the Earth's average radius and The product of and gives the actual spherical distance between the two points, rather than the straight-line distance, which conforms to the true spatial relationship of the Earth's curved surface.

[0063] In some embodiments, after constructing a beam cone by using the spatial location of the SAR payload platform as the vertex and each vertex of the surface projection polygon as the base vertex, and configuring the triangular facets with color and semi-transparent material to reflect the field of view direction and aperture characteristics during display, i.e. after the aforementioned S150, the visualization processing method of the Web-based SAR field of view projection based on the four corner points may further include the following steps:

[0064] S160. Generate contour lines according to the order of polygon vertices. Contour lines support both solid and dashed line types.

[0065] S170. In dashed line mode, select to configure the dashed line spacing and gap parameters in pixels or in geographic length; the dashed line spacing and gap parameters can be configured in pixels or in geographic length.

[0066] S180: Configure the line width, color, and transparency, and visually coordinate them with the projection surface material.

[0067] In this application, it is understood that the application supports generating both solid and dashed outlines. The appropriate line type can be selected based on different visualization needs (such as distinguishing different SAR payload fields of view and highlighting key coverage areas), enhancing the distinguishability of the field of view boundaries. This application provides dashed line parameter configuration modes in both pixel and geographic length units, adapting to the lightweight requirements of web-based screen displays while also meeting the need for precise display based on actual geographic spatial scales, thus improving the method's scenario adaptability. Furthermore, this application avoids visual conflicts between the outlines and the projection surface by customizing the line width, color, and transparency, and achieving visual coordination with the projection surface material. This makes the entire visualization interface clearer and further enhances the visual recognition of the SAR field of view coverage, helping users locate and distinguish field of view areas and improving the user experience and usability of web-based interactive viewing. Based on this, this application, through configurable outline types and materials, improves boundary readability and layer collaborative display effects, making it suitable for application scenarios such as multi-satellite mission situation visualization, imaging coverage assessment, and interactive planning.

[0068] In some embodiments, before calculating the azimuth angles and spherical geodesic distances of the four corner points relative to the center point, with the center point as the reference origin, to determine the starting angle and spanning angle of the sector angle domain, i.e. before the aforementioned S120, the visualization processing method based on the web-based SAR field-of-view projection of the four corner points may further include the following steps:

[0069] S111. Based on the latitude, longitude, and elevation coordinates of the satellite's center point, and the latitude, longitude, and elevation coordinates of the four corner points of the SAR payload's field of view on the Earth's surface, the longitude in the data is normalized from 0° to 360°, and the latitude is normalized... Use a 90°-90° constraint and adjust the height accordingly based on the actual situation.

[0070] Understandably, this application normalizes longitude from 0° to 360° and normalizes latitude. The 90°-90° constraint unifies the range of coordinate data values, avoiding calculation logic confusion or formula errors caused by latitude and longitude exceeding the standard range, and ensuring the effectiveness of subsequent geometric calculations such as azimuth and spherical distance. At the same time, it supplements the height data according to the actual situation, ensuring the integrity of the three-dimensional coordinates of latitude, longitude and height, and solving problems such as insufficient projection fit and beam cone construction deviation that may be caused by missing data. It provides standardized and missing basic data for the entire visualization process, improving the accuracy of calculation and rendering from the source.

[0071] S112. Record rendering controls, including the number of sampling segments, fill color and transparency, outline width, and virtual / real parameters, in the form of configuration items.

[0072] Understandably, this application uses configuration items to uniformly record rendering control parameters such as the number of sampling segments, fill color, and transparency, achieving centralized management and flexible configuration of rendering parameters. This allows users to quickly adjust parameters according to different visualization needs (such as scene display, data analysis, and report generation), improving the interactivity and scene adaptability of the method. Furthermore, the standardized configuration item recording method enables rendering parameters to be directly read and called by the web-based 3D rendering engine, simplifying the logic of parameter passing and parsing, reducing the complexity of engineering implementation, and providing a convenient modification entry point for subsequent function expansion and parameter optimization, thus improving the maintainability of the method.

[0073] The following will describe in more detail the technical solution of the visualization processing method for Web-based SAR field-of-view projection based on four corner points provided in this application, with reference to a more specific embodiment, so that those skilled in the art can intuitively understand the overall process and specific implementation of this application after reading it.

[0074] This embodiment is based on the Cesium 3D engine. By obtaining the center point of the SAR payload and the four corner points of the field of view on the ground at a certain moment, the fan-shaped projection area of ​​the field of view is obtained through spherical geometry calculation, and the corresponding ground coverage polygon and optional 3D beam cone are drawn in the Web 3D scene to realize the intuitive display of the SAR field of view.

[0075] It should be noted that the SAR payload in this embodiment can be spaceborne SAR, airborne SAR, or ground-based SAR. This embodiment uses spaceborne SAR as an example for illustration, but this does not constitute a limitation on the application scenario. Specifically, the visualization processing method for web-based SAR field-of-view projection based on four corner points can be implemented based on the following steps:

[0076] (1) Obtain the latitude, longitude and elevation coordinates of the center point and four corner points of the SAR field of view on the ground at the current time, and obtain the configuration parameters related to visualization.

[0077] Specifically, the center point is the geographical location of the current SAR imaging area on the Earth's surface, and the four corner points are the four boundary points of the field of view projected onto the Earth's surface. The latitude, longitude, and altitude coordinates mentioned above can come from the orbit simulation system, attitude calculation system, or data files obtained through offline calculation.

[0078] Optionally, the visualization configuration parameters include: fill color and transparency of the ground coverage area, type of boundary outline, outline width, dashed line spacing, number of field-of-view sampling segments, whether to draw a 3D beam cone, and beam cone height scaling factor, etc. In this embodiment, the relevant parameters can be configured by the user through the front-end interface or issued by the back-end service. Please refer to the spherical interpolation sampling diagram provided in Figure 2. Figure 2 shows the spherical interpolation sampling logic of the SAR field-of-view surface projection sector area: with the satellite center point as the origin, the inner and outer arcs of the sector area are sampled respectively through radial azimuth discrete lines. The inner arc sampling corresponds to the near edge (inner edge radius range) of the SAR field of view, and the outer arc sampling corresponds to the far edge (outer edge radius range).

[0079] To improve numerical stability and ease of interpretation, this embodiment performs 0°-360° normalization on the longitude after reading the latitude and longitude, and performs normalization on the latitude. 90°-90° range check; for input data that clearly exceeds the range, an alarm can be triggered or the data can be discarded before visualization to avoid abnormal projection results.

[0080] (2) Using the center point as a reference, calculate the azimuth angles of the four corner points relative to the center point and the spherical geodesic distance.

[0081] Specifically, for any corner point, its height component is first adjusted using an optional height correction or ignored to obtain its projection onto a reference ellipsoid. Then, based on spherical trigonometry or ellipsoidal geodetic formulas, the spherical geodesic distance of the corner point relative to the center point and its azimuth relative to true north are calculated. The azimuth value is normalized to between 0° and 360° for subsequent sorting and comparison.

[0082] Optionally, to simplify calculations, this embodiment may use an approximate spherical model, or a standard ellipsoidal model may be used for distance and azimuth calculations in scenarios requiring higher accuracy. Both are within the scope of protection of this invention.

[0083] (3) Based on the geodesic distance and range relationship of the four corner points, determine the inner and outer radii of the sector, as well as the starting azimuth and span angle of the sector.

[0084] Specifically, the distances between the four corner points are compared, and the two points with smaller distances are considered inner boundary corner points, while the two points with larger distances are considered outer boundary corner points. Furthermore, based on the azimuth angles of the corner points, the four corner points are sorted in ascending order of azimuth angle to obtain an ordered sequence.

[0085] When the azimuth angle spans 0° or 360°, this embodiment normalizes the azimuth angle within the 0°-360° range by translation, compares the span angle under different translation methods, and selects the angular region with the smallest span angle that can cover all corner points as the angular region of the field of view sector, thereby obtaining the starting azimuth angle and span angle of the sector. In this way, even if the field of view crosses the prime meridian, it can ensure that the obtained sector is a continuous region without gaps or reverse loops.

[0086] Optionally, when the SAR operating mode is more complex, additional parameters such as the SAR beam pointing angle and platform height can be used to fine-tune the inner and outer radii. For example, the inner radius can be corrected according to the imaging elevation angle to more accurately reflect the effective imaging area. Such modifications do not change the core idea of ​​this invention.

[0087] (4) Within the defined sector angle domain, perform spherical interpolation on the inner and outer boundaries to generate the vertex set of the field projection polygon.

[0088] Specifically, within the sector-shaped angular domain, equal-angle discretization is performed according to a preset number of segments to obtain a series of discrete azimuth angles. For each discrete azimuth angle, the latitude and longitude coordinates of the corresponding inner and outer boundary points are calculated using the inner and outer radii as inputs for the spherical forward calculation.

[0089] Then, the inner boundary points are added to the vertex set in ascending order of azimuth angle, and the outer boundary points are added to the vertex set in descending order of azimuth angle, ultimately resulting in a closed vertex sequence. Optionally, to explicitly close the polygon, a starting vertex can be added again at the end of the vertex sequence to form a topologically closed polygon outline.

[0090] To balance rendering performance and shape detail, the number of segments in this embodiment can be adaptively adjusted according to the projection size of the field of view on the screen. When the camera is close, the number of segments is increased to obtain smooth arcs; when the camera is far away, the number of segments is decreased to reduce the number of vertices and improve overall rendering performance.

[0091] (5) Convert the generated polygon vertices from latitude, longitude and height coordinates to scene coordinates used by the Web 3D engine, and draw the field projection surface on the Earth model surface.

[0092] Specifically, for each polygon vertex, its latitude and longitude can first be converted into a three-dimensional coordinate vector in a geocentric geofixed coordinate system. Then, using the interface provided by the Web 3D engine, combined with terrain height data, it is mapped onto the visualization scene. Subsequently, a two-dimensional polygon is constructed with the vertex sequence as the boundary, and pre-configured fill color and transparency are set to generate a SAR coverage area that fits the ground surface.

[0093] Optionally, to avoid flickering between polygons and terrain tiles, the field of view projection surface can be raised by a small offset in height, such as several meters. This height offset can be preset or dynamically calculated based on the current camera height.

[0094] (6) Generate contour lines on the field of view projection polygon and control the line type of the contour lines according to the configuration parameters.

[0095] Specifically, a closed polyline is constructed as the outline based on a sequence of polygon vertices, and the width of the outline is determined by the pixel width configured by the user. For scenes requiring a dashed line effect, a polyline material or a custom shader can be used to segment the polyline in geographic space according to the preset dashed line length and interval, thereby presenting the dashed outline in the Web 3D engine.

[0096] Furthermore, based on the obtained ground field of view projection, a corresponding three-dimensional SAR beam cone is constructed to enhance the perception of field of view direction and spatial opening angle.

[0097] Specifically, the spatial coordinates of the SAR payload platform can be obtained, and this location can be used as the vertex of the beam cone. Then, the four corner points are raised to a preset height in the scene coordinate system, or the intersection of the line connecting the satellite altitude and the geocenter of the corner points can be used directly as the bottom vertices of the beam cone. Triangular patches are formed by the vertex and the two adjacent bottom vertices, and four connected triangular patches are constructed in sequence to obtain the complete beam side surface.

[0098] During visualization, a slightly transparent material and a color consistent with or similar to the field of view projection can be applied to the sides of the beam so that users can simultaneously observe the ground coverage area and the spatial beam range. Depending on the needs, only partial patches can be drawn or inner cones can be added to represent different operating modes or field of view ranges at different confidence levels.

[0099] In some embodiments, this application provides a web-based SAR field-of-view projection visualization system 400 based on four corner points, as shown in FIG3. The web-based SAR field-of-view projection visualization system 400 based on four corner points may include the following modules:

[0100] The coordinate acquisition module 410 is used to acquire the latitude, longitude, and elevation coordinates of the satellite's center point, as well as the latitude, longitude, and elevation coordinates of the four corner points of the SAR payload's field of view on the Earth's surface.

[0101] The sector angle domain determination module 420 is used to calculate the azimuth angle and spherical geodesic distance of the four corner points relative to the center point, with the center point as the reference origin, so as to determine the starting angle and spanning angle of the sector angle domain.

[0102] The sector angle domain analysis module 430 is used to discretize the azimuth angles at equal intervals within the sector angle domain according to a preset number of segments. For each discrete azimuth angle, the spherical forward solution is performed with the inner edge radius and the outer edge radius respectively to obtain the inner arc point sequence and the outer arc point sequence. The inner arc point sequence is arranged in descending order of azimuth, and the outer arc point sequence is arranged in ascending order of azimuth. They are spliced ​​together to form a closed set of vertices of a polygonal surface. The same vertex is added to the beginning and end of the closed set of vertices of a polygonal surface to make the rendering closed.

[0103] The projection processing module 440 is used to convert polygon vertices from latitude, longitude, and height coordinates to three-dimensional scene coordinates, generate polygon entities that fit the ground reference surface, enable point-by-point height mode so that the vertex elevation takes effect point by point; generate the ground projection surface in the browser-side three-dimensional rendering engine and set the fill material and transparency parameters.

[0104] The display processing module 450 is used to construct a beam cone by using the spatial position of the SAR payload platform as the vertex and the vertices of the surface projection polygon as the base vertices. The module configures the triangular facets with color and semi-transparent material to reflect the field of view direction and opening characteristics during the display process.

[0105] According to embodiments of this application, any multiple modules among the coordinate acquisition module 410, the sector angle domain determination module 420, the sector angle domain analysis module 430, the projection processing module 440, and the display processing module 450 can be combined into one module, or any one of these modules can be split into multiple modules. Alternatively, at least some of the functions of one or more of these modules can be combined with at least some of the functions of other modules and implemented in one module.

[0106] The modules in the system shown in Figure 3 have the functions to implement each step of the aforementioned visualization processing method based on the four corner points of the Web-based SAR field of view projection, and can achieve the corresponding technical effects. For the sake of brevity, they will not be described in detail here.

[0107] In some embodiments, this application provides an electronic device, the structural schematic of which is shown in FIG4.

[0108] The electronic device may include a processor 510 and a memory 520 storing computer program instructions.

[0109] Specifically, the processor 510 may include a central processing unit (CPU), an application-specific integrated circuit (ASIC), or one or more integrated circuits that can be configured to implement the embodiments of this application.

[0110] Memory 520 may include mass storage for data or instructions. For example, and not limitingly, memory 520 may include a hard disk drive (HDD), floppy disk drive, flash memory, optical disk, magneto-optical disk, magnetic tape, or Universal Serial Bus (USB) drive, or a combination of two or more of these. Where appropriate, memory 520 may include removable or non-removable (or fixed) media. Where appropriate, memory 520 may be internal or external to the integrated gateway disaster recovery device. In a particular embodiment, memory 520 is non-volatile solid-state memory.

[0111] Memory 520 may include read-only memory (ROM), random access memory (RAM), disk storage media device, optical storage media device, flash memory device, electrical, optical, or other physical / tangible memory storage device. Therefore, typically, memory 520 includes one or more tangible (non-transitory) computer-readable storage media (e.g., memory devices) encoded with software including computer-executable instructions, and when the software is executed (e.g., by one or more processors), it can perform the operations described in any of the four-corner-based web-based SAR field-of-view projection visualization processing methods in the above embodiments.

[0112] The processor 510 reads and executes computer program instructions stored in the memory 520 to implement any of the visualization processing methods for Web-based SAR field-of-view projection based on four corner points in the above embodiments.

[0113] In one example, the electronic device may also include a communication interface 530 and a bus 500. As shown in Figure 4, the processor 510, memory 520, and communication interface 530 are connected via the bus 500 and communicate with each other.

[0114] The communication interface 530 is mainly used to realize communication between various modules, devices, units and / or equipment in the embodiments of this application.

[0115] Bus 500 includes hardware, software, or both, that couples components of an online data traffic metering device together. For example, and not limitingly, the bus may include an Accelerated Graphics Port (AGP) or other graphics bus, an Enhanced Industry Standard Architecture (EISA) bus, a Front Side Bus (FSB), HyperTransport (HT) interconnect, an Industry Standard Architecture (ISA) bus, an Infinite Bandwidth Interconnect, a Low Pin Count (LPC) bus, a memory bus, a Microchannel Architecture (MCA) bus, a Peripheral Component Interconnect (PCI) bus, a PCI-Express (PCI-X) bus, a Serial Advanced Technology Attachment (SATA) bus, a Video Electronics Standards Association Local (VLB) bus, or other suitable buses, or combinations of two or more of these. Where appropriate, bus 500 may include one or more buses. Although specific buses are described and illustrated in embodiments of this application, this application contemplates any suitable bus or interconnect.

[0116] Furthermore, in conjunction with the visualization processing method for Web-based SAR field-of-view projection based on four corner points in the above embodiments, this application embodiment can provide a computer storage medium for implementation. The computer storage medium stores computer program instructions; when these computer program instructions are executed by a processor, they implement any of the visualization processing methods for Web-based SAR field-of-view projection based on four corner points in the above embodiments.

[0117] It should be clarified that this application is not limited to the specific configurations and processes described above and shown in the figures. For the sake of brevity, detailed descriptions of known methods are omitted here. In the above embodiments, several specific steps are described and shown as examples. However, the method process of this application is not limited to the specific steps described and shown. Those skilled in the art can make various changes, modifications, and additions, or change the order of steps, after understanding the spirit of this application.

[0118] The functional blocks shown in the above block diagram can be implemented as hardware, software, firmware, or a combination thereof. When implemented in hardware, they can be, for example, electronic circuits, application-specific integrated circuits (ASICs), appropriate firmware, plug-ins, function cards, etc. When implemented in software, the elements of this application are programs or code segments used to perform the required tasks. Programs or code segments can be stored on a machine-readable medium or transmitted over a transmission medium or communication link via data signals carried on a carrier wave. "Machine-readable medium" can include any medium capable of storing or transmitting information. Examples of machine-readable media include electronic circuits, semiconductor memory devices, ROM, flash memory, erasable ROM (EROM), floppy disks, CD-ROMs, optical disks, hard disks, fiber optic media, radio frequency (RF) links, etc. Code segments can be downloaded via computer networks such as the Internet, intranets, etc.

[0119] It should also be noted that the exemplary embodiments mentioned in this application describe methods or systems based on a series of steps or apparatus. However, this application is not limited to the order of the above steps; that is, the steps can be performed in the order mentioned in the embodiments, or in a different order, or several steps can be performed simultaneously.

[0120] The aspects of this disclosure have been described above with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this disclosure. It should be understood that each block in the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing apparatus to produce a machine such that these instructions, executable via the processor of the computer or other programmable data processing apparatus, enable the implementation of the functions / actions specified in one or more blocks of the flowchart illustrations and / or block diagrams. Such a processor can be, but is not limited to, a general-purpose processor, a special-purpose processor, a special application processor, or a field-programmable logic circuit. It is also understood that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can also be implemented by special-purpose hardware performing the specified functions or actions, or can be implemented by a combination of special-purpose hardware and computer instructions.

[0121] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A visualization processing method for web-based SAR field-of-view projection based on four corner points, characterized in that, include: Obtain the latitude, longitude, and elevation coordinates of the satellite's center point, as well as the latitude, longitude, and elevation coordinates of the four corner points of the SAR payload's field of view on the Earth's surface; Using the center point as the reference origin, calculate the azimuth angles and spherical geodesic distances of the four corner points relative to the center point to determine the starting angle and spanning angle of the sector angle domain. Discretize the azimuth angles at equal intervals according to a preset number of segments within the sector angle domain. Perform spherical forward solutions on each discrete azimuth angle using the inner and outer edge radii to obtain the inner arc point sequence and the outer arc point sequence. Arrange the inner arc point sequence in descending order of azimuth and the outer arc point sequence in ascending order of azimuth, and splice them together to form a closed set of vertices of a surface polygon. Add the same vertex to the beginning and end of the closed set of vertices of the surface polygon to make the rendering closed. Convert the polygon vertices from latitude, longitude, and height coordinates to 3D scene coordinates, generate polygon entities that fit the ground reference surface, and enable point-by-point height mode so that the vertex elevation takes effect point by point. In the browser-side 3D rendering engine, a ground projection surface is generated and the fill material and transparency parameters are set. Using the spatial location of the SAR payload platform as the vertex and each vertex of the ground projection polygon as the bottom edge vertex, a beam cone is formed by constructing a triangular facet that connects end to end. Colors and semi-transparent materials are configured for the triangular facet to reflect the field of view direction and opening characteristics during the display process.

2. The visualization processing method for Web-based SAR field-of-view projection based on four corner points as described in claim 1, characterized in that, The step of using the center point as the reference origin to calculate the azimuth angles and spherical geodesic distances of the four corner points relative to the center point to determine the starting angle and spanning angle of the sector angle domain includes: using the center point as the reference origin to convert the coordinates of the center point and the four corner points into radians; using spherical trigonometry formulas to calculate the azimuth angle of each corner point relative to the center point; and using the semi-versus formula as the geodesic length calculation model to calculate the spherical distance from the center point to each corner point, wherein the azimuth angle is defined as 0° for true north and ranges from 0° to 360° in the clockwise direction; The corner points are sorted in descending order based on the spherical distances. The two corner points with the largest distance are selected as the outer edge point pair, and the average spherical distance of the outer edge point pair is calculated as the outer edge radius of the sector. The two corner points with the smallest distance are selected as the inner edge point pair, and the average spherical distance of the inner edge point pair is calculated as the inner edge radius of the sector. The azimuth information of the corner points in the outer edge point pair is analyzed to determine the starting angle and spanning angle of the sector. When the sector spans 0° or 360°, angle normalization is performed to maintain azimuth continuity.

3. The visualization processing method for Web-based SAR field-of-view projection based on four corner points as described in claim 2, characterized in that, The analysis of the azimuth information of the midpoint of the outer edge point pair to determine the starting angle and spanning angle of the sector angle domain includes: extracting the first azimuth and second azimuth of the outer edge point pair in a clockwise direction, and calculating the azimuth difference between the first azimuth and the second azimuth in a clockwise direction; if the azimuth difference is less than or equal to 180°, determining that the starting angle of the sector angle domain is equal to the first azimuth, and the spanning angle of the sector angle domain is equal to the azimuth difference; if the azimuth difference is greater than 180°, determining that the starting angle of the sector angle domain is equal to the second azimuth, and the spanning angle of the sector angle domain is the difference between 360° and the azimuth difference.

4. The visualization processing method for Web-based SAR field-of-view projection based on four corner points as described in claim 2, characterized in that, The coordinates of the center point are: The coordinates of any corner point are ,in, Indicates the first Longitude of each corner point Indicates the first The latitude of each corner point; The azimuth angle of each corner point relative to the center point satisfies the expression: ;in, It is the azimuth angle. Represents the arctangent function in the four quadrants. and It is an intermediate variable and satisfies the expression: In the formula, Due to the difference in longitude, and ， Indicates the longitude of the center point. Indicates the latitude of the center point. Represents the sine function. Represents the cosine function; the spherical distance from the center point to each corner point satisfies the expression: In the formula, Represents spherical distance. This represents the average radius of the Earth.

5. The visualization processing method for Web-based SAR field-of-view projection based on four corner points as described in any one of claims 1-4, characterized in that, After constructing a beam cone by using the spatial location of the SAR payload platform as the vertex and the vertices of the surface projection polygon as the base vertices, and configuring the triangular facets with colors and semi-transparent materials to reflect the field of view direction and opening characteristics during display, the visualization processing method for web-based SAR field of view projection based on the four corner points further includes: generating contour lines according to the order of polygon vertices, wherein the contour lines support both solid and dashed line types; in dashed line mode, configuring the dashed line interval and gap parameters in pixels or geographic length; wherein the dashed line interval and gap parameters can be configured in pixels or geographic length; configuring the line width, color, and transparency, and visually coordinating them with the projection surface material.

6. The visualization processing method for Web-based SAR field-of-view projection based on four corner points as described in any one of claims 1-4, characterized in that, The latitude, longitude, and elevation coordinates of the satellite's center point, as well as the latitude, longitude, and elevation coordinates of the four corner points of the SAR payload's field of view on the Earth's surface, are a combination of longitude, latitude, and elevation, with the elevation taken as the Earth's surface elevation or the elevation of a designated reference surface. The center point is the projection center of the field of view on the ground or the equivalent sub-satellite point. The four corner points are determined according to the logical relationship of left outer, right outer, right inner, and left inner to determine the left and right boundaries and the inner and outer boundaries, which are automatically identified by azimuth sorting when no order is provided.

7. The visualization processing method for Web-based SAR field-of-view projection based on four corner points as described in any one of claims 1-4, characterized in that, Before calculating the azimuth angles and spherical geodesic distances of the four corner points relative to the center point, using the center point as the reference origin, to determine the starting angle and spanning angle of the sector angle domain, the visualization processing method for the Web-based SAR field-of-view projection based on the four corner points further includes: normalizing the longitude from 0° to 360° in the data based on the latitude, longitude, and elevation coordinates of the satellite's center point and the latitude, longitude, and elevation coordinates of the four corner points of the SAR payload's field of view on the Earth's surface, and normalizing the latitude... Set 90°-90° constraints and adjust the height according to the actual situation; record rendering controls including the number of sampling segments, fill color and transparency, outline width and virtual / real parameters in the form of configuration items.

8. A visualization processing system for web-based SAR field-of-view projection based on four corner points, characterized in that, include: The coordinate acquisition module is used to acquire the latitude, longitude, and altitude coordinates of the satellite's center point, as well as the latitude, longitude, and altitude coordinates of the four corner points of the SAR payload's field of view on the Earth's surface. The sector angle domain determination module is used to calculate the azimuth angle and spherical geodesic distance of the four corner points relative to the center point, with the center point as the reference origin, to determine the starting angle and spanning angle of the sector angle domain. The sector angle domain analysis module is used to discretize the azimuth angles at equal intervals within the sector angle domain according to a preset number of segments, and perform spherical forward solutions on each discrete azimuth angle with the inner edge radius and outer edge radius respectively to obtain the inner arc point sequence and the outer arc point sequence. The inner arc point sequence is arranged in descending order of azimuth, and the outer arc point sequence is arranged in ascending order of azimuth, splicing them together to form a closed set of vertices of a surface polygon. The same vertex is appended to the beginning and end of the closed set of vertices of the surface polygon to make the rendering closed. The projection processing module is used to convert polygon vertices from latitude, longitude, and height coordinates to three-dimensional scene coordinates, generate polygon entities that fit the ground reference surface, and enable point-by-point height mode so that the vertex elevation takes effect point by point. Generate the ground projection surface and set the fill material and transparency parameters in the browser-side 3D rendering engine; The display processing module is used to construct a beam cone by using the spatial location of the SAR payload platform as the vertex and the vertices of the surface projection polygon as the base vertices. The module configures the triangular facets with colors and semi-transparent materials to reflect the field of view direction and opening characteristics during the display process.

9. An electronic device, characterized in that, include: A processor, a memory, and a program stored in the memory and executable on the processor, wherein the program, when executed by the processor, implements the visualization processing method for web-based SAR field-of-view projection based on four corner points as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a program or instructions that, when executed by a processor, implement the visualization processing method for Web-based SAR field-of-view projection based on four corner points as described in any one of claims 1 to 7.

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