An earth observation system based on a single measuring station and its observation method

Abstract

The present application provides an earth observation system based on a single measuring station, and the working modes of its earth observation payload include: record first and then replay mode, in which the imaging window is earlier than the data transmission window, and the imaging window and the data transmission window do not overlap; replay first and then record mode, in which the data transmission window is earlier than the imaging window, and the data transmission window and the imaging window do not overlap, and the record file and the replay file are not the same file; replay first and then record and play mode, in which the imaging window is located in the data transmission window, and the record file and the replay file are not the same file; replay first and then quasi-real transmission mode: the data transmission window includes two data transmission segments, the first data transmission segment is used to replay historical files, and the second data transmission segment is used for quasi-real transmission, the imaging window does not overlap with the first data transmission segment, and partially overlaps with the second data transmission segment. The present application ensures the flexibility of the user's observation area, the timeliness of data, and the observation efficiency by designing a new payload mode, and effectively improves the earth observation efficiency of a single measuring station.

Description

Technical Field

[0001] The present application as a whole relates to a method for improving earth observation efficiency based on a single measuring station, which belongs to the field of remote sensing satellite system engineering and is applicable to effectively improving the earth observation efficiency of remote sensing satellites in orbit under a single measuring station condition. Background Art

[0002] How to make full use of a single observation station under limited resource conditions and design a load pattern to maximize the observation efficiency of a single observation station is an important issue.

[0003] Traditional payload modes primarily include payload recording, data playback, and simultaneous recording and playback (including real-time and quasi-real-time modes). These modes offer advantages in terms of simple and understandable logic and relatively convenient on-orbit operations and mission planning. However, they also have drawbacks for single stations, such as difficulties in fully utilizing the capabilities of ground stations and ensuring both imaging location flexibility and timely data download, particularly for imaging and data download in neighboring regions of the user country. Summary of the Invention

[0004] In view of the fact that traditional payload modes are difficult to fully utilize a single observation station under limited resource conditions, it is difficult to fully exert the effectiveness of the ground station, and it is difficult to simultaneously ensure the flexibility of the imaging location and the timeliness of data transmission, especially the needs of neighboring areas of the user country cannot be effectively and timely monitored, this application proposes a ground observation method based on a single observation station.

[0005] This application provides an Earth observation method based on a single observation station. By designing a new payload mode, it effectively improves the Earth observation efficiency of a single observation station, solves the effective observation needs of neighboring areas of the user country, and ensures the flexibility of the observation area, timeliness of data and observation efficiency.

[0006] The present application provides an Earth observation system based on a single observation station. The system has an Earth observation payload. The operating modes of the Earth observation payload include:

[0007] Record first and then replay mode. In this record first and then replay mode, the imaging window is earlier than the data transmission window, and the imaging window and the data transmission window do not overlap;

[0008] Playback before recording mode: In this playback before recording mode, the data transmission window is earlier than the imaging window, and the data transmission window and the imaging window do not overlap, and the recording file and the playback file are not the same file;

[0009] Playback first and then record and play mode: In this playback first and then record and play mode, the imaging window is located in the data transmission window, and the recording file and the playback file are not the same file;

[0010] Playback first, then quasi-real transmission mode: In this playback first, then quasi-real transmission mode, the data transmission window includes two data transmission segments. The first data transmission segment is used to play back historical files, and the second data transmission segment is used for quasi-real transmission. The imaging window has no overlap with the first data transmission segment and partially overlaps with the second data transmission segment.

[0011] In at least one embodiment, the record-first-then-playback mode is used in the following scenario: the imaging area is adjacent to the user's country, and the remote sensing satellite is required to immediately download image data when passing by.

[0012] In at least one embodiment, the playback-then-record mode is used in the following scenario: the imaging area is adjacent to the user's country, and the imaging area is required to be able to be photographed immediately when the remote sensing satellite passes over it.

[0013] In at least one embodiment, the playback-first-then-record-while-playing mode is used in the following scenarios: the imaging area is located within the measurement and control range of a single measuring station, and the remote sensing satellite is required to replay historical data throughout the transit arc, and the remote sensing satellite records data during imaging in the middle section.

[0014] In at least one embodiment, the playback-first-then-quasi-real-time transmission mode is used in the following scenarios: the imaging area is located within the measurement and control range of a single measuring station, and the remote sensing satellite is required to replay historical data in the first half of the transit arc, and record and replay the imaging area in the second half, and the imaging data is downloaded in real time.

[0015] In at least one embodiment, in the playback-then-record mode, the camera is powered on before the data transmission window ends to avoid command conflicts.

[0016] In at least one embodiment, in the playback-first-then-record-while-playing mode, the camera is turned on after the playback starts to avoid command conflicts. Before sending the serial playback command, the storage recording command is first sent to make the storage enter the record-while-playing mode, and the recording action is started after the camera forms an image.

[0017] In at least one embodiment, in the playback-first-then-quasi-real-transmission mode, the camera is powered on before the end of the first data transmission window to avoid command conflicts.

[0018] The present application also provides a method for performing earth observation using the above earth observation system, comprising:

[0019] S1: Determine whether the Earth observation scenario belongs to one of the following scenarios:

[0020] Scenario 1: The imaging area is adjacent to the user's country, and the remote sensing satellite is required to immediately download image data when passing over it;

[0021] Scenario 2: The imaging area is adjacent to the user's country, and the remote sensing satellite is required to be able to capture the imaging area immediately when passing over it;

[0022] Scenario 3: The imaging area is within the measurement and control range of a single station. The remote sensing satellite is required to replay historical data throughout the transit arc and record data during mid-segment imaging.

[0023] Scenario 4: The imaging area is within the measurement and control range of a single station. The remote sensing satellite is required to replay historical data in the first half of the transit arc, and record and replay the imaging area in the second half, with the imaging data being transmitted in real time.

[0024] S2: If the Earth observation scenario belongs to the first scenario, select the record-then-playback mode for the Earth observation payload:

[0025] S3: If the Earth observation scenario belongs to the second scenario, the Earth observation payload operating mode is selected as playback-first-record mode;

[0026] S4: If the Earth observation scenario belongs to the third scenario, the Earth observation payload operation mode is selected as playback first and then recording and playing mode;

[0027] S5: If the earth observation scenario belongs to the fourth scenario, the working mode of the earth observation payload is selected as the playback first and then quasi-real transmission mode.

[0028] The present application also provides a computer-readable storage medium having software instructions stored thereon, wherein the software instructions implement the above method when executed.

[0029] This application designs a new payload mode, taking into account the special needs of neighboring areas of the user country and the timing relationship between the power on and off of various satellite equipment, while ensuring the flexibility, data timeliness and observation efficiency of the user's observation area, which can effectively improve the earth observation efficiency of a single station. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The following will further illustrate the above-mentioned characteristics, technical features, advantages and implementation methods of the present application in a clear and understandable manner through the description of preferred embodiments and in conjunction with the accompanying drawings. The following drawings are intended only to illustrate and explain the present application and do not limit the scope of the present application. Among them:

[0031] Figure 1a and Figure 1b This is a schematic diagram of the in-orbit operation of a sun-synchronous orbit remote sensing satellite;

[0032] Figure 2 One of the on-orbit usage scenarios is shown;

[0033] Figure 3 The second on-orbit usage scenario is shown;

[0034] Figure 4 The third on-orbit usage scenario is shown;

[0035] Figure 5 The fourth on-orbit usage scenario is shown;

[0036] Figure 6 The record-then-playback mode of the Earth Observation payload is shown;

[0037] Figure 7 The playback-then-record mode of the Earth Observation payload is shown;

[0038] Figure 8 The playback-first-then-record-while-playing mode of the Earth Observation payload is shown;

[0039] Figure 9 The playback-then-quasi-real-time transmission mode of the Earth observation payload is shown. DETAILED DESCRIPTION

[0040] In order to have a clearer understanding of the technical features, purposes and effects of this application, the specific implementation methods of this application are now described with reference to the accompanying drawings.

[0041] Traditional payload modes primarily include payload recording, data playback, and simultaneous recording and playback (including real-time and quasi-real-time modes). These modes offer advantages in terms of simple and understandable logic, and relatively convenient on-orbit operations and mission planning. However, they also have drawbacks for single stations, such as difficulties in fully utilizing the capabilities of ground stations and ensuring both flexible imaging locations and timely data download.

[0042] Schematic diagram of the operation of sun-synchronous orbit remote sensing satellite in orbit Figure 1a and Figure 1b As shown. Figure 1a Points C and D are the boundary points between the shadow area and the sunlit area, and points A and B are the symmetrical points of points D and C respectively. Figure 1b The middle arc MN is the sub-satellite point trajectory of the satellite transit circle, O is the position of the single station in the user country, PQ is the transit effective arc of the single station, the black solid circle is the measurement and control range of the single station O, and the light gray rectangular area represents the user country area.

[0043] During orbit, when a user country has only a single observation station, to maximize the use of PQ resources within the transit arc, the satellite typically operates in a payload recording and playback mode during the daytime transit arc (A-B) in the sunlit region, and in a payload data playback mode during the nighttime transit arc (C-D) in the shadowed region. At other times, the satellite selectively operates in a payload recording mode during the remaining transit arcs (A-B) in the sunlit region, maximizing the amount of image data that can be downloaded daily. This approach is logically simple and convenient for on-orbit operation, but it struggles to fully utilize the ground station's capabilities for a single station, and lacks flexibility in imaging locations and timely data downloads.

[0044] In order to fully utilize the effectiveness of the ground station under the conditions of a single measuring station, it is necessary to meet the requirements of the following on-orbit usage scenarios.

[0045] Scenario 1: The imaging area is adjacent to the user's country, and the image data is required to be downloaded immediately when the border is crossed, while ensuring that the resources of the border arc are not wasted. Figure 2 As shown, the rectangular hatched area is the imaging area.

[0046] Scenario 2: The imaging area is adjacent to the user's country, and it is required that the transit arc resources are not wasted and the imaging area can be photographed immediately after transit. Figure 3 As shown, the rectangular hatched area is the imaging area.

[0047] Scenario 3: The imaging area is a certain area within the measurement and control range of a single station, and historical data is required to be played back throughout the transit arc, and the satellite can record data in the middle of the imaging. Figure 4 As shown, the rectangular hatched area is the imaging area.

[0048] Scenario 4: The imaging area is a certain area within the measurement and control range of a single measuring station, but the historical data needs to be played back in the first half of the transit arc, and the imaging area needs to be recorded and played back in the second half, and the imaging data needs to be downloaded immediately. Figure 5 As shown, the rectangular hatched area is the imaging area.

[0049] Using traditional payload modes, a single mode alone cannot meet the requirements of Scenario 1. Considering a simple combination of payload recording mode and payload data playback mode, the satellite equipment will be shut down after the payload recording mode ends and powered on before the payload data playback mode begins. This will result in a significant waste of transit arc resources and the inability to fully transmit image data to the ground during the transit, thus still failing to meet this requirement.

[0050] Using traditional payload modes, a single mode alone cannot achieve the requirements of Scenario 2. Considering a simple combination of payload data playback mode and payload recording mode, the satellite equipment will be powered off after the payload data playback mode ends and powered on before the payload recording mode begins. This will result in the satellite already having left the imaging area by the time imaging begins after the transit arc playback ends, thus still failing to meet this requirement.

[0051] Using traditional payload modes, the requirements of scenario 3 cannot be met by using only a single mode because the timing of each mode is different. If a simple splicing combination is considered, this requirement cannot be met because the timing is different and simple splicing of satellite recording and playback commands will cause command conflicts.

[0052] Using traditional payload modes, due to their different timings, a single mode alone cannot meet the requirements of Scenario 4. Considering a simple combination of payload data playback mode and payload recording and playback mode, the satellite equipment will be powered off after the payload data playback mode ends and powered on before the payload recording and playback mode begins. This will result in the satellite already having left the imaging area when imaging begins after playback ends, thus still failing to meet this requirement.

[0053] In summary, existing Earth observation methods cannot meet the requirements of the above scenarios. Under limited resource conditions, it is difficult to fully utilize a single observation station, it is difficult to fully utilize the effectiveness of ground stations, and it is difficult to simultaneously ensure the flexibility of imaging locations and the timeliness of data transmission, especially imaging and timely data transmission in neighboring areas of user countries.

[0054] The present invention proposes a method for Earth observation based on a single measuring station, which adopts an improved payload mode design and can effectively address the needs that cannot be achieved by traditional payload modes. While ensuring the full utilization of transit arc resources, it achieves the flexibility of imaging locations and the timeliness of data transmission, effectively improving the observation efficiency of a single measuring station.

[0055] The new load mode design based on a single measuring station is not a simple splicing of traditional load modes, but a "seamless" compatible conversion of different modes based on comprehensive consideration of multiple factors to ensure the correct instruction sequence in engineering. This application fully considers the following factors:

[0056] (a) Reduce the shutdown of satellite equipment during mode switching to shorten the switching time. However, the logic and compatibility of the various command sequences during the switching must be fully considered to avoid command conflicts that may cause satellite failures.

[0057] (b) Consider the command sequence within the same subsystem, as well as the compatibility of command sequences and interfaces between subsystems to avoid satellite failures. For example, the power on / off sequence, data transmission, recording, and playback sequence between the camera subsystem and the data transmission subsystem.

[0058] (c) Take full account of the time intervals between recording, playback, and recording and playing simultaneously, and set a reasonable timing sequence;

[0059] (d) Relevant constraints when designing commands, such as the interval between commands received by the same slave computer, the maximum single operating time of the camera, the maximum single operating time of the data transmission, etc.

[0060] Substituting the classical satellite parameters, the new payload mode design based on a single station proposed in this application is as follows:

[0061] Notation and constraints:

[0062] T1 - the time when the imaging task starts (the time when valid image data starts to be recorded);

[0063] T2 - the start time of the data transmission task (the time when data download begins);

[0064] W——Camera effective imaging time;

[0065] ti - recording time of a single file.

[0066] E——data transmission task time (the time between storage playback and playback stop);

[0067] i#——recording / playback file number;

[0068] Camera startup time: ≥36s

[0069] Maximum single power-on time of the camera: 10 minutes

[0070] Maximum single power-on time for digital transmission: 15 minutes

[0071] The interval between receiving commands from the same slave computer: ≥2s

[0072] According to one embodiment of the present application, a single-station-based earth observation system is provided. The system includes an earth observation payload. The operating modes of the earth observation payload include:

[0073] (1) Record-then-playback mode (M1): In this mode, the operating sequence of the Earth observation payload is as follows: Figure 6 As shown, the imaging window is earlier than the data transmission window, and the imaging window and the data transmission window do not overlap.

[0074] This new payload mode, M1, allows imaging areas adjacent to the user country, requiring immediate download of image data during transit, while ensuring that resources in the transit arc are not wasted. While ensuring full utilization of transit arc resources, it also enables flexibility in imaging locations and timely data download, effectively improving the observation efficiency of a single station.

[0075] (2) Playback and then record mode (M2): In this mode, the working sequence of the earth observation payload is as follows: Figure 7 As shown in the figure, the data transmission window is earlier than the imaging window, and the data transmission window and the imaging window do not overlap, and the recording file and the playback file are not the same file;

[0076] To avoid command conflicts, in this mode, the camera is powered on before the data transmission window ends.

[0077] This new payload mode, M2, allows for imaging areas adjacent to the user country, ensuring that transit arc resources are fully utilized and that imaging areas can be captured immediately upon transit. This ensures full utilization of transit arc resources while achieving flexibility in imaging locations, effectively improving the observation efficiency of a single station.

[0078] (3) Playback first and then record and play mode (M3): In this mode, the working sequence of the earth observation payload is as follows: Figure 8 As shown in the figure, the imaging window is located in the data transmission window, and the recording file and the playback file are not the same file.

[0079] To avoid command conflicts, the camera should be powered on after playback begins. Since the persistent storage does not support receiving recording commands during playback to enter the recording-while-playing mode, you must first send the persistent storage recording command before sending the sequence playback command to put the persistent storage into the recording-while-playing mode (however, no data will be received from the front end at this time). Then, start recording the action after the camera forms an image.

[0080] This new payload mode, M3, allows imaging of a specific area within the measurement and control range of a single station, while also enabling full playback of historical data throughout the transit arc and enabling the satellite to image and record data mid-segment. While ensuring full utilization of transit arc resources, it also enables flexibility in imaging locations and timely data download, effectively improving the observation efficiency of a single station.

[0081] (4) Playback first and then quasi-real transmission mode (M4): In this mode, the working sequence of the earth observation payload is as follows: Figure 9 As shown, the data transmission window includes two data transmission segments, the first data transmission segment is used to play back historical files, and the second data transmission segment is used for quasi-real transmission. The imaging window has no overlap with the first data transmission segment and partially overlaps with the second data transmission segment.

[0082] To avoid command conflicts, the camera is powered on before the end of the first data transmission window.

[0083] This new payload mode, M4, allows imaging of a specific area within the measurement and control range of a single station. However, it requires playback of historical data for the first half of the transit arc, while recording and recording the imaging area for the second half, with immediate downlink of imaging data. While ensuring full utilization of transit arc resources, it also achieves flexibility in imaging locations and timely data downlink, effectively improving the observation efficiency of a single station.

[0084] The following describes the technical solution of the present application in detail in conjunction with a specific embodiment of the present application. An embodiment of the present application provides a single-station-based earth observation method, which utilizes the above-described observation system to perform earth observation. The earth observation method includes:

[0085] S1: Determine which of the following scenarios the Earth observation scenario belongs to:

[0086] Scenario 1: The imaging area is adjacent to the user's country, and the remote sensing satellite is required to immediately download image data when passing through the circle to ensure that resources in the passing arc are not wasted.

[0087] Scenario 2: The imaging area is adjacent to the user's country, and the remote sensing satellite is required to immediately capture the imaging area when passing through to ensure that resources in the passing arc are not wasted;

[0088] Scenario 3: The imaging area is within the measurement and control range of a single station. The remote sensing satellite is required to replay historical data throughout the transit arc and record data during mid-segment imaging.

[0089] Scenario 4: The imaging area is within the measurement and control range of a single station. The remote sensing satellite is required to replay historical data in the first half of the transit arc, and record and replay the imaging area in the second half, with the imaging data being transmitted in real time.

[0090] S2: If the Earth observation scenario belongs to scenario 1, select the record-then-playback mode (M1) for the Earth observation payload. In this mode, the imaging window is earlier than the data transmission window, and there is no overlap.

[0091] S3: If the Earth observation scenario belongs to scenario 2, the Earth observation payload operating mode is selected as playback-first-record mode (M2). In this mode, the data transmission window is earlier than the imaging window, there is no overlap, and the recording file and the playback file are different files;

[0092] S4: If the Earth observation scenario belongs to scenario 3, the Earth observation payload operating mode is selected as playback first and then recording and playing mode (M3). In this mode, the imaging window is located in the data transmission window, and the recording file and the playback file are different files.

[0093] S5: If the Earth observation scenario belongs to scenario 4, the working mode of the Earth observation payload is selected as the playback-first-then-quasi-real-time transmission mode (M4). In this mode, the data transmission window is divided into two data transmission segments. The first data transmission segment is used for the playback history file, and the second data transmission segment is used for quasi-real-time transmission. The imaging window has no overlap with the first data transmission segment and partially overlaps with the second data transmission segment.

[0094] The earth observation method based on a single measuring station provided by the present invention can meet the requirements of the satellite's in-orbit working conditions for the flexibility of imaging locations and the timeliness of data transmission, while ensuring the full utilization of transit arc resources. It realizes the scenario requirements that traditional payload modes cannot meet, solves the demand problems in the use of several types of single measuring stations, and effectively improves the earth observation efficiency of single measuring stations.

[0095] This invention is also compatible with traditional payload modes. Satellite operations on-orbit are typically categorized into routine and special missions. When user missions don't require flexibility in imaging locations or timely data downloads, traditional payload modes can be used, ensuring ease of understanding and convenient on-orbit operation. However, when users require flexibility in imaging locations or timely data downloads, new payload modes can be selected based on scenario requirements to further enhance observation efficiency.

[0096] It should be understood that although this specification is described according to various embodiments, not every embodiment contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

[0097] The above description is only an illustrative embodiment of the present application and is not intended to limit the scope of the present application. Any equivalent changes, modifications and combinations made by any person skilled in the art without departing from the concept and principle of the present application shall fall within the scope of protection of the present application.

Claims

1. A single-station Earth observation system having an Earth observation payload, wherein the operating modes of the Earth observation payload include: Record first and then replay mode. In this record first and then replay mode, the imaging window is earlier than the data transmission window, and the imaging window and the data transmission window do not overlap; Playback before recording mode: In this playback before recording mode, the data transmission window is earlier than the imaging window, and the data transmission window and the imaging window do not overlap, and the recording file and the playback file are not the same file; Playback first and then record and play mode: In this playback first and then record and play mode, the imaging window is located in the data transmission window, and the recording file and the playback file are not the same file; Playback first, then quasi-real transmission mode: In this playback first, then quasi-real transmission mode, the data transmission window includes two data transmission segments. The first data transmission segment is used to play back historical files, and the second data transmission segment is used for quasi-real transmission. The imaging window has no overlap with the first data transmission segment and partially overlaps with the second data transmission segment.

2. The system according to claim 1, wherein: The record-first-then-playback mode is used in the following scenarios: the imaging area is adjacent to the user's country, and the remote sensing satellite is required to immediately download image data when it passes over the area.

3. The system according to claim 1, wherein: The playback-then-record mode is used in the following scenarios: the imaging area is adjacent to the user's country, and the imaging area needs to be captured immediately when the remote sensing satellite passes over it.

4. The system according to claim 1, wherein: The playback-first-then-record-while-playing mode is used in the following scenarios: the imaging area is within the measurement and control range of a single station, and the remote sensing satellite is required to replay historical data throughout the transit arc, and the remote sensing satellite records data during mid-segment imaging.

5. The system according to claim 1, wherein The playback-first, then quasi-real-time transmission mode is used in the following scenarios: the imaging area is located within the measurement and control range of a single measuring station, and the remote sensing satellite is required to replay historical data in the first half of the transit arc, and record and replay the imaging area in the second half, and the imaging data is transmitted in real time.

6. The system according to claim 1, wherein: In playback-then-record mode, the camera is powered on before the data transmission window ends to avoid command conflicts.

7. The system according to claim 1, wherein: In the playback first and then record while playing mode, The camera is turned on after playback starts to avoid command conflicts. Before sending the serial playback command, send the persistent storage record command first to put the persistent storage into the recording and playback mode, and start recording the action after the camera forms an image.

8. The system according to claim 1, wherein: In the playback-first-then-real-time transmission mode, the camera is powered on before the end of the first data transmission window to avoid command conflicts.

9. A method for Earth observation based on a single observation station, using the Earth observation system according to claim 1 to perform Earth observation, the method comprising: S1: Determine whether the Earth observation scenario belongs to one of the following scenarios: Scenario 1: The imaging area is adjacent to the user's country, and the remote sensing satellite is required to immediately download image data when passing over it; Scenario 2: The imaging area is adjacent to the user's country, and the remote sensing satellite is required to be able to capture the imaging area immediately when passing over it; Scenario 3: The imaging area is within the measurement and control range of a single station. The remote sensing satellite is required to replay historical data throughout the transit arc and record data during mid-segment imaging. Scenario 4: The imaging area is within the measurement and control range of a single station. The remote sensing satellite is required to replay historical data in the first half of the transit arc, and record and replay the imaging area in the second half, with the imaging data being transmitted in real time. S2: If the Earth observation scenario belongs to the first scenario, select the record-then-playback mode for the Earth observation payload: S3: If the Earth observation scenario belongs to the second scenario, the Earth observation payload operating mode is selected as playback-first-record mode; S4: If the Earth observation scenario belongs to the third scenario, the Earth observation payload operation mode is selected as playback first and then recording and playing mode; S5: If the earth observation scenario belongs to the fourth scenario, the working mode of the earth observation payload is selected as the playback first and then quasi-real transmission mode.

10. A computer-readable storage medium having stored thereon software instructions that, when executed, implement the method of claim 9.

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