Visual analysis method for spatial domain directivity of satellite

Abstract

The invention discloses a satellite airspace directivity visualization analysis method comprising the following steps: establishing an STK simulation scene, and adding a satellite and a satellite load sensor in the STK simulation scene; obtaining the time-varying characteristics of the satellite load sensor pointing angle through a satellite airspace pointing mode, and generating a load sensor pointing file; loading a pointing angle file on the satellite load sensor in the STK simulation scene and applying the pointing angle file; and setting simulation scene time, starting simulation, generating a satellite airspace directivity animation and a satellite airspace directivity report, and realizing visual analysis and verification of the satellite airspace directivity condition. According to the invention, based on the satellite orbit and the load sensor capability parameters, the satellite airspace directivity and time change relationship is established, and the visual verification of the satellite over-the-ground coverage area and the change condition is realized.

Description

Technical Field

[0001] The present invention relates to the field of satellite remote sensing technology, and in particular to a method for visually analyzing satellite airspace pointing characteristics. Background Art

[0002] The current airspace working modes of remote sensing satellite sensors are mainly divided into three categories, namely strip mode, beam mode and scanning mode.

[0003] In strip mode, the antenna's pointing direction remains fixed. As the satellite platform moves at a constant speed, the antenna sweeps across targets on the Earth's surface, acquiring uninterrupted remote sensing data. During operation, the antenna beam's azimuth, elevation, and beamwidth parameters remain fixed. The beam follows the satellite's translation, mapping a single strip across the Earth's surface, hence the name "strip mode."

[0004] In spotlight mode, the antenna beam is controlled to illuminate targets on the Earth's surface for extended periods, acquiring continuous remote sensing data. This mode is typically used for remote sensing of known key target areas, allowing for long-term continuous observations within a limited detection area. For SAR imaging satellites, spotlight mode enables the acquisition of higher-resolution SAR images.

[0005] In scanning mode, the antenna beam is controlled to scan the airspace at a constant rate, achieving wide coverage of the Earth's surface. This mode is typically used for wide-area search and discovery, and is effective for full airspace situational awareness and target detection and identification. This mode requires consideration of the dwell time of each antenna pointing direction and the switching method of the antenna beam. This ensures that the antenna covers the Earth's surface without omission, thus ensuring the integrity of the airspace scanning remote sensing data.

[0006] Existing research on satellite airspace pointing primarily focuses on its impact on imaging algorithms. Satellite airspace pointing characteristics are typically mathematically deduced from theoretical formulas. For example, Chinese invention patent CN105184002B provides a simulation analysis method for digital antenna pointing angles. This method uses numerical calculations to simulate and analyze digital antenna pointing angles, but the process is abstract and complex, making it difficult to understand and demonstrate. For more complex scanning patterns, the antenna's coverage of the Earth's surface depends on a variety of factors, including satellite flight speed, antenna dwell time, antenna scanning period, antenna beamwidth, and beam pointing switching methods. Visual analysis methods are urgently needed to verify the reliability of the mathematical deductions and the rationality of the airspace pointing design. Summary of the Invention

[0007] In order to solve the technical problems existing in the above-mentioned prior art, the purpose of the present invention is to provide a method for visual analysis of satellite airspace pointing characteristics. Based on the satellite orbit and payload sensor capability parameters, the relationship between satellite airspace pointing characteristics and time changes is established, and the all-round and visual analysis capability of satellite airspace pointing characteristics is realized, thereby improving the efficiency of satellite sensor airspace working mode design.

[0008] To achieve the above-mentioned object of the invention, the present invention provides a method for visually analyzing satellite airspace pointing characteristics, comprising the following steps:

[0009] Step S1, establishing an STK simulation scene, and adding a satellite and a satellite payload sensor to the STK simulation scene;

[0010] Step S2: obtaining the time-varying characteristics of the satellite payload sensor pointing angle through the satellite airspace pointing mode, and generating a payload sensor pointing file;

[0011] Step S3, loading the pointing angle file on the satellite payload sensor in the STK simulation scene and applying it;

[0012] Step S4: Set the simulation scene time and start the simulation to generate a satellite airspace pointing characteristic animation and a satellite airspace pointing characteristic report to achieve visual analysis and verification of the satellite airspace pointing situation.

[0013] According to a technical solution of the present invention, in step S1, it specifically includes:

[0014] The satellite orbit parameters and payload sensor capability parameters are set according to the actual simulation requirements. The satellite orbit parameters include the semi-major axis, eccentricity, orbit inclination, right ascension of the ascending node, argument of perigee and mean anomaly of the satellite orbit. The payload sensor capability parameters include the beam width and the position of the sensor relative to the satellite.

[0015] According to a technical solution of the present invention, in step S2, it specifically includes:

[0016] Step S21: In the satellite airspace pointing mode, according to the simulation task requirements, obtain a satellite payload sensor pointing angle and time relationship table;

[0017] Step S22: Create an STK sensor pointing file based on the satellite payload sensor pointing angle and time relationship table. The elements in the STK sensor pointing file include sensor pointing simulation time, sensor pointing azimuth angle, and sensor pointing pitch angle.

[0018] According to a technical solution of the present invention, the simulation time resolution of the sensor pointing simulation time is no greater than the simulation time resolution of the STK simulation scene.

[0019] According to a technical solution of the present invention, in step S22, the following steps are specifically included:

[0020] The representation mode of the STK sensor pointing file is selected, and the sensor pointing coordinate conversion is performed on the satellite payload sensor pointing angle and time relationship table according to the selected representation mode.

[0021] According to a technical solution of the present invention, the representation mode of the STK sensor pointing file is an azimuth / pitch angle representation mode, a quaternion representation mode, a pitch / yaw / roll angle representation mode or an Euler angle representation mode.

[0022] According to a technical solution of the present invention, in step S1, the number of the satellite payload sensors is one or more.

[0023] According to a technical solution of the present invention, in step S1, the number of the satellites is one or more.

[0024] According to a technical solution of the present invention, in step S4, the simulation scene time is set within the interval of the sensor pointing simulation time in the STK sensor pointing file; the analysis time of the satellite airspace pointing characteristic report is consistent with the sensor pointing simulation time in the STK sensor pointing file.

[0025] According to a technical solution of the present invention, the satellite airspace pointing characteristic report includes analysis time, longitude and latitude coordinates of the center of the satellite sensor's ground coverage area, and the coverage area radius.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] The visualization analysis of satellite airspace pointing characteristics provided by the present invention can display the complex and diverse satellite sensor airspace pointing characteristics through a two-dimensional / three-dimensional map window animation, and can intuitively and clearly analyze the satellite airspace work execution status, which is practical for the satellite sensor airspace mode design.

[0028] The present invention can personalize the sensor pointing file according to the characteristics of the satellite sensor, has strong versatility, and is applicable to various types of remote sensing satellites, various types of sensors, and various airspace working modes.

[0029] The satellite airspace pointing characteristics visualization analysis method proposed in the present invention is scalable and can be applied to the coordinated and parallel operation of multiple sensors on satellites and multiple sensors in multi-satellite constellations. It has the ability to analyze the complex and diverse airspace pointing characteristics of multiple sensors. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be derived from these drawings without inventive effort.

[0031] Figure 1 Schematically showing a flow chart of a method for visually analyzing satellite airspace pointing characteristics according to one embodiment of the present invention;

[0032] Figure 2 Schematic representation of the two-dimensional ground coverage diagram according to the satellite airspace working mode - strip scanning;

[0033] Figure 3 Schematic representation of the satellite's airspace operating mode - a three-dimensional diagram of ground coverage during strip scanning;

[0034] Figure 4 Schematic representation of the two-dimensional ground coverage diagram of the satellite airspace working mode - beamforming mode;

[0035] Figure 5 Schematic representation of the three-dimensional ground coverage diagram in the satellite airspace working mode - beamforming mode;

[0036] Figure 6 Schematic representation of the two-dimensional ground coverage diagram of the satellite airspace working mode - scanning mode;

[0037] Figure 7 Schematic representation of the three-dimensional ground coverage of the satellite in the airspace working mode - beamforming mode. DETAILED DESCRIPTION

[0038] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the embodiments. Obviously, the drawings described below only illustrate some embodiments of the present invention. For those skilled in the art, other drawings can be derived from these drawings without inventive effort.

[0039] like Figure 1 As shown, the present invention provides a method for visually analyzing satellite-satellite airspace pointing characteristics, and its specific steps are as follows:

[0040] Step S1: Create an STK simulation scene and add satellites and satellite payload sensors to the simulation scene;

[0041] The number of satellites is one or more, and the number of satellite payload sensors is one or more.

[0042] When adding satellites and satellite payload sensors, the satellite orbit parameters and payload sensor capability parameters are set according to actual simulation requirements. The satellite orbit parameters include the satellite semi-major axis, eccentricity, orbit inclination, right ascension of the ascending node, argument of perigee, mean anomaly, etc. The payload sensor capability parameters include beam width, sensor position relative to the satellite, etc.

[0043] In this example, the simulation time is set from 04:00:00 on August 26, 2024, to 04:00:00 on August 27, 2024, with a time resolution of 1 second. The satellite's semi-major axis is set to 6678.14 km, the orbital inclination is 28.5°, the eccentricity is 0, the right ascension of the ascending node is 0°, the argument of perigee is 0°, and the mean anomaly is 0°. The payload sensor half-beamwidth is set to 17°, and the payload sensor is located at the center of the satellite.

[0044] Step S2: Calculate the time-varying characteristics of the satellite payload sensor pointing angle through the satellite airspace pointing mode, and generate a payload sensor pointing file;

[0045] In step S2, it specifically includes:

[0046] Step S21: In the satellite airspace pointing mode, according to the simulation task requirements, obtain a satellite payload sensor pointing angle and time relationship table;

[0047] Step S22: Create an STK sensor pointing file based on the satellite payload sensor pointing angle and time relationship table. The elements in the STK sensor pointing file include sensor pointing simulation time, sensor pointing azimuth angle, and sensor pointing pitch angle.

[0048] Satellite airspace pointing modes include strip mode, spotlight mode, and scanning mode. In this embodiment, the scanning mode is selected as the satellite airspace pointing mode. Based on the satellite airspace scanning mode, a table of the relationship between the satellite payload sensor pointing angle and time is obtained and generated as a .sp file in the STK sensor pointing file format. The file contains elements such as the sensor pointing simulation time, the sensor pointing azimuth angle, and the sensor pointing pitch angle. The simulation time resolution can be set as required, but should not exceed the scene simulation time resolution.

[0049] When creating an STK sensor pointing file, first select the STK sensor pointing file representation mode, and then perform sensor pointing coordinate conversion on the satellite payload sensor pointing angle and time relationship table based on the selected representation mode. The STK sensor pointing file representation mode can be the azimuth / pitch angle representation mode (AttitudeTimeAzElAngles mode), the quaternion representation mode (AttitudeTimeQuaternions mode), the pitch / yaw / roll angle representation mode (AttitudeTimeYPRAngles mode), or the Euler angle representation mode (AttitudeTimeEulerAngles mode).

[0050] When the STK sensor pointing file is in AttitudeTimeAzElAngles mode, the sensor pointing azimuth is defined as the angle between the projection of the satellite payload sensor's center on the XOY plane of the satellite coordinate system and the +X axis; the sensor pointing pitch angle is defined as the angle between the projection of the satellite payload sensor's center on the XOY plane of the satellite coordinate system and the +X axis. The sensor pointing coordinate system conversion is completed automatically.

[0051] In this embodiment, the payload sensor performs a two-dimensional full-space scan in azimuth and elevation, with each beam pointing dwell time of 2 seconds. A table showing the relationship between beam pointing and time variation can be generated, as shown in Table 1 below. The table automatically converts the sensor pointing coordinate system.

[0052] Simulation scene moments Time(s) Azimuth (°) Pitch angle (°) August 26, 2024, 04:18:30 1110 209.8375665 19.20747973 August 26, 2024, 04:18:31 1111 209.8375665 19.20747973 August 26, 2024, 04:18:32 1112 206.3410011 23.92746472 August 26, 2024, 04:18:33 1113 206.3410011 23.92746472 August 26, 2024, 04:18:34 1114 201.8815068 28.02432067 August 26, 2024, 04:18:35 1115 201.8815068 28.02432067 August 26, 2024, 04:18:36 1116 196.4845652 31.32130438 August 26, 2024, 04:18:37 1117 196.4845652 31.32130438 August 26, 2024, 04:18:38 1118 190.2720573 33.64408738 August 26, 2024, 04:18:39 1119 190.2720573 33.64408738 August 26, 2024, 04:18:40 1120 183.4922646 34.8474773 August 26, 2024, 04:18:41 1121 183.4922646 34.8474773 … … … … August 26, 2024, 04:23:05 1385 356.5077354 34.8474773 August 26, 2024, 04:23:06 1386 3.492264603 34.8474773 August 26, 2024, 04:23:07 1387 3.492264603 34.8474773 August 26, 2024, 04:23:08 1388 10.27205732 33.64408738 August 26, 2024, 04:23:09 1389 10.27205732 33.64408738 August 26, 2024, 04:23:10 1390 16.48456516 31.32130438 August 26, 2024, 04:23:11 1391 16.48456516 31.32130438 August 26, 2024, 04:23:12 1392 21.88150682 28.02432067 August 26, 2024, 04:23:13 1393 21.88150682 28.02432067 August 26, 2024, 04:23:14 1394 26.34100107 23.92746472 August 26, 2024, 04:23:15 1395 26.34100107 23.92746472 August 26, 2024, 04:23:16 1396 29.83756648 19.20747973 August 26, 2024, 04:23:17 1397 29.83756648 19.20747973

[0053] Table 1 is made into a .sp file according to the STK sensor pointing file format. The file format is shown in Table 2 below:

[0054]

[0055]

[0056] Table 2

[0057] Step S3: Load the pointing angle file on the satellite payload sensor in the STK simulation scene and apply it;

[0058] In the STK simulation scene, select the Pointing option in the Basic settings of the satellite payload sensor to be set, select External as the pointing method, add the .sp file generated in step S2 and apply it to make the pointing file effective.

[0059] Step S4: Set the simulation scene time and start the simulation to generate a satellite airspace pointing characteristic animation and a satellite airspace pointing characteristic report to achieve visual analysis and verification of the satellite airspace pointing situation.

[0060] By setting the simulation time in the STK simulation scene and starting the simulation, you can generate an animation that displays the satellite's airspace pointing characteristics. You can also use reports to obtain the center and radius of the satellite sensor's ground coverage area, enabling visual analysis and verification of satellite airspace scanning. The satellite airspace pointing characteristics report includes the analysis time, the latitude and longitude coordinates of the satellite sensor's ground coverage area center, and the coverage area radius.

[0061] The simulation scenario time should be set within the range of the sensor pointing simulation time in the STK sensor pointing file; the analysis time of the satellite airspace pointing characteristics report should be consistent with the sensor pointing simulation time in the STK sensor pointing file.

[0062] Set the scene simulation time according to the initial sensor pointing simulation time in the STK sensor pointing file. After starting the simulation, you can observe the 2D / 3D map window animation showing the satellite airspace scanning over time on the 2D Graphics / 3D Graphics page. You can also generate a Boresight Intersection report based on the simulation time period to assist in analyzing the latitude and longitude at the center of the satellite sensor's ground coverage area and the coverage radius.

[0063] In this embodiment, the simulation scene time is set to 04:18:30-04:23:17 on August 26, 2024. After starting the simulation, the two-dimensional / three-dimensional map window can be observed on the 2D Graphics / 3D Graphics page to show how the satellite airspace scan changes over time.

[0064] Select the Projection option in the 2D Graphics settings of the sensor and set the Persistence Time to 60s. The 2D / 3D map window will display the coverage of the earth's surface when the satellite sensor performs airspace scanning, such as Figure 6 、 Figure 7 The Boresight Intersection report can be used to analyze the latitude and longitude coordinates of the center of the satellite sensor's ground coverage area and the coverage area radius from 04:18:30 to 04:23:17 on August 26, 2024, to accurately analyze and verify the satellite's airspace scanning situation. The report is shown in Table 3 below.

[0065]

[0066]

[0067] Table 3

[0068] The present invention provides a method for visual analysis of satellite airspace pointing characteristics. With the help of a powerful satellite analysis engine, the method realistically and accurately simulates the airspace pointing characteristics of satellite sensors, provides a visual analysis tool to realize animation display in a two-dimensional / three-dimensional map window, and generates comprehensive data reports for further analysis and research. The method has strong scalability and can perform visual simulation analysis on multiple satellites and multiple sensors at the same time, realizing the comprehensive and visual analysis capability of satellite airspace pointing characteristics, and improving the efficiency of satellite sensor airspace working mode design.

[0069] It should be noted that the above is a preferred embodiment of the present invention. It should be noted that although the preferred embodiment of the present invention has been described, it is clear that those skilled in the art, once they understand the basic inventive concept of the present invention, can make various improvements and modifications without departing from the principles of the present invention. Such improvements and modifications should also be considered as within the scope of protection of the present invention. Therefore, the appended claims are intended to be interpreted as including the preferred embodiment and all changes and modifications that fall within the scope of the embodiments of the present invention.

Claims

1. A method for visual analysis of satellite airspace pointing characteristics, characterized in that: The following steps are involved: Step S1, establishing an STK simulation scene, and adding a satellite and a satellite payload sensor to the STK simulation scene; Step S2: obtaining the time-varying characteristics of the satellite payload sensor pointing angle through the satellite airspace pointing mode, and generating a payload sensor pointing file; Step S3, loading the pointing angle file on the satellite payload sensor in the STK simulation scene and applying it; Step S4: Set the simulation scene time and start the simulation to generate a satellite airspace pointing characteristic animation and a satellite airspace pointing characteristic report to achieve visual analysis and verification of the satellite airspace pointing situation.

2. The satellite spatial pointing characteristics visualization analysis method according to claim 1, characterized in that: In the step S1, it specifically includes: The satellite orbit parameters and payload sensor capability parameters are set according to the actual simulation requirements. The satellite orbit parameters include the semi-major axis, eccentricity, orbit inclination, right ascension of the ascending node, argument of perigee and mean anomaly of the satellite orbit. The payload sensor capability parameters include the beam width and the position of the sensor relative to the satellite.

3. The satellite airspace pointing characteristics visualization analysis method according to claim 2, characterized in that: In the step S2, it specifically includes: Step S21: In the satellite airspace pointing mode, according to the simulation task requirements, obtain a satellite payload sensor pointing angle and time relationship table; Step S22: Create an STK sensor pointing file based on the satellite payload sensor pointing angle and time relationship table. The elements in the STK sensor pointing file include sensor pointing simulation time, sensor pointing azimuth angle, and sensor pointing pitch angle.

4. The satellite spatial pointing characteristics visualization analysis method according to claim 3, characterized in that: The simulation time resolution of the sensor pointing simulation time is no greater than the simulation time resolution of the STK simulation scene.

5. The satellite airspace pointing characteristics visualization analysis method according to claim 3, characterized in that: In the step S22, it specifically includes: The representation mode of the STK sensor pointing file is selected, and the sensor pointing coordinate conversion is performed on the satellite payload sensor pointing angle and time relationship table according to the selected representation mode.

6. The method for visual analysis of satellite spatial pointing characteristics according to claim 5, characterized in that: The representation mode of the STK sensor pointing file is an azimuth / pitch angle representation mode, a quaternion representation mode, a pitch / yaw / roll angle representation mode, or an Euler angle representation mode.

7. The method for visual analysis of satellite spatial pointing characteristics according to claim 1, characterized in that: In step S1, the number of the satellite payload sensors is one or more.

8. The satellite airspace pointing characteristics visualization analysis method according to claim 1, characterized in that: In step S1, the number of satellites is one or more.

9. The method for visual analysis of satellite spatial pointing characteristics according to claim 2, characterized in that: In step S4, the simulation scene time is set within the interval of the sensor pointing simulation time in the STK sensor pointing file; the analysis time of the satellite airspace pointing characteristic report is consistent with the sensor pointing simulation time in the STK sensor pointing file.

10. The satellite airspace pointing characteristics visualization analysis method according to claim 1, characterized in that: The satellite airspace pointing characteristics report includes analysis time, longitude and latitude coordinates of the center of the satellite sensor's ground coverage area, and the coverage area radius.

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