Multi-frequency satellite earth observation task decomposition method based on space-time grid

Abstract

The invention relates to the technical field of giant satellite group constellation remote sensing satellite operation control, and discloses a multi-frequency satellite earth observation task decomposition method based on a space-time grid. The method comprises the following steps: firstly, constructing a satellite earth observation task space-time grid, and filling access data of satellites; inputting observation frequency requirements including observation positions, time periods, times, resolution, loads and the like; obtaining a related space-time grid according to the position; obtaining sequence information of related satellite access in the space-time grid according to the requirements of time period, frequency, resolution, load and the like; establishing a multi-frequency satellite earth observation evaluation function, and integrating factors such as a time interval, satellite side sway and the number of satellites; a multi-frequency satellite earth observation evaluation function is utilized, satellite grid element tasks which meet requirements and are accessed for n times are optimized to serve as a task decomposition scheme, and n is the frequency number required by the decomposition. The method has the characteristics of comprehensive consideration factors, good expandability, good reliability and the like.

Description

Technical Field

[0001] The present invention relates to the field of remote sensing satellite operation control technology, and in particular to a multi-frequency satellite earth observation task decomposition method based on a space-time grid, which can be used in application scenarios such as remote sensing satellite cluster joint mission planning, giant cluster constellation collaborative planning, and space-ground integrated satellite operation control. Background Art

[0002] There are several main methods for multi-frequency task decomposition in the field of remote sensing satellite operation control, but they have certain defects in the comprehensiveness of overall planning factors and iterative optimization effects:

[0003] (1) Operators directly decompose multi-frequency tasks based on actual user needs and satellite operating status, combined with their own business experience. This method is the current mainstream method, which is time-consuming and labor-intensive and requires human participation throughout the process. The multi-frequency satellite mission decomposition solution obtained is not optimal.

[0004] (2) Using the time period equalization method, this method directly divides the multi-frequency satellite earth observation time period according to the frequency, and then finds a satellite observation task in each time period to form the final multi-frequency satellite earth observation plan. This method does not consider the number of satellites consumed by the multi-frequency and whether there is a satellite access in the equalization interval.

[0005] (3) A multi-frequency satellite earth observation mission decomposition method based on knowledge graph guidance. This method builds and retrieves complex constraints based on knowledge graph to meet the requirements of multi-frequency mission planning. This method relies too much on the knowledge in the knowledge graph. If the rules and knowledge are insufficient, it will not achieve a good decomposition effect. Summary of the invention

[0006] The purpose of the present invention is to avoid the shortcomings of the above-mentioned background technology and provide a multi-frequency satellite earth observation task decomposition method based on space-time grid, which has the characteristics of comprehensive consideration of factors, good scalability, good reliability, etc., and is suitable for use in fields such as remote sensing satellite operation control.

[0007] The technical solution adopted by the present invention is:

[0008] A multi-frequency satellite earth observation task decomposition method based on space-time grid includes the following steps:

[0009] Step 1: construct a space-time grid for satellite earth observation missions and calculate satellite access information; store satellite access information according to the grid geographic location to form a space-time grid for satellite earth observation;

[0010] Step 2: Obtain observation frequency requirements, including observation location, time period, number of times, resolution, and load requirements;

[0011] Step 3, obtaining the relevant satellite earth observation space-time grid according to the observation position;

[0012] Step 4, obtaining the access sequence information of the relevant satellites in the satellite earth observation space-time grid according to the time period, number of times, resolution and payload requirements;

[0013] Step 5, establishing a multi-frequency satellite earth observation evaluation function by integrating the time interval, satellite sway and the number of satellites;

[0014] Step 6: According to the observation frequency requirements, generate n observation arrangement schemes based on the access sequence information obtained in step 4 multiple times, and use the multi-frequency satellite earth observation evaluation function to obtain the evaluation value of each arrangement scheme, and select the optimal multi-frequency observation scheme; where n is the number of observation frequencies required for this decomposition.

[0015] Furthermore, the specific process of step 1 is as follows:

[0016] Step 101, constructing a space-time grid data structure of a satellite earth observation mission, wherein the structure includes a grid number, grid longitude and latitude, satellite code, access time, satellite payload type, satellite payload resolution, satellite payload working mode, satellite side swing angle, and solar altitude angle;

[0017] Step 102, calculating satellite access information for all satellites participating in the multi-frequency earth observation mission, the calculation results including access time, satellite payload resolution, satellite payload working mode, satellite side swing angle and solar altitude angle;

[0018] Step 103, storing satellite access information according to the grid geographical location to form a satellite earth observation space-time grid.

[0019] Furthermore, in the observation frequency requirements of step 2: the observation position refers to the geographical location that the satellite wants to observe the earth, which is composed of latitude and longitude data; the time period refers to the start time and end time when the geographical location is required to be observed; the number of times refers to the number of times the geographical location is required to be observed within the specified time; the resolution refers to the satellite payload resolution required to be observed at the geographical location within the specified time; the payload refers to the satellite payload type required to be observed at the geographical location within the specified time.

[0020] Furthermore, the specific process of step 3 is as follows:

[0021] According to the observation location in the observation frequency requirement, that is, the longitude and latitude information, the corresponding location is retrieved in the satellite earth observation space-time grid to obtain the corresponding grid number.

[0022] Furthermore, the specific process of step 4 is as follows:

[0023] Step 401, retrieving access sequence information of relevant satellites in the relevant satellite earth observation space-time grid according to the logical order of time period, payload and resolution;

[0024] Step 402: If the satellite access times retrieved in step 401 are not less than the required observation frequency, proceed to the next step; if they are less than the required observation frequency, terminate the task and report an error.

[0025] Furthermore, the multi-frequency satellite earth observation evaluation function established in step 5 is:

[0026]

[0027] In the formula, represents the satellite earth observation evaluation function of the t-th multi-frequency combination, represents the satellite quantity adjustment coefficient, represents the number of satellites in the t-th multi-frequency combination, represents the satellite side swing angle adjustment coefficient, represents the roll angle corresponding to the jth observation of the i-th satellite of the t-th multi-frequency combination; represents the number of satellite observations of the t-th multi-frequency combination; represents the average observation interval of the t-th multi-frequency combination; An adjustment factor that represents the average observation interval.

[0028] Furthermore, the specific process of step 6 is as follows:

[0029] Step 601, in the satellite earth observation space-time grid, according to the observation frequency requirement, the satellite grid element task of n visits that meets the requirement is selected from the access sequence information obtained in step 4 as the task decomposition scheme; wherein n is the number of observation frequencies required for this decomposition;

[0030] Step 602, using a multi-frequency satellite earth observation evaluation function to calculate the evaluation value of this arrangement scheme;

[0031] Step 603, return to step 601, and compare the evaluation value calculated this time with the evaluation value calculated last time. If it is better than the evaluation value calculated last time, the arrangement scheme is retained, otherwise it is not retained.

[0032] Step 604, continue step 601 to step 603 until the evaluation value stops increasing or the number of iterations reaches an upper limit, and the optimal multi-frequency observation scheme is obtained.

[0033] Compared with the background technology, the present invention has the following advantages:

[0034] 1. The present invention proposes a multi-frequency satellite earth observation task decomposition method based on space-time grid, which overcomes the shortcomings of existing methods such as insufficient scalability, reliance on manual experience, and waste of satellite resources, and improves the performance of complex task decomposition in the context of giant star cluster constellations.

[0035] 2. The present invention has good practical application and automated collaborative performance, and can meet the application requirements of collaborative planning of multi-satellite missions of remote sensing satellites. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a schematic diagram of the process of the present invention.

[0037] Figure 2 It is a schematic diagram of the spatiotemporal grid data structure of the present invention.

[0038] Figure 3 It is a schematic diagram of the spatiotemporal grid retrieval process of the present invention. DETAILED DESCRIPTION

[0039] The present invention will be further explained below in conjunction with the accompanying drawings.

[0040] like Figure 1 As shown, a multi-frequency satellite earth observation task decomposition method based on space-time grid includes the following steps:

[0041] Step 1: construct a space-time grid for satellite earth observation missions and calculate satellite access information; store satellite access information according to the grid's geographic location to form a space-time grid for satellite earth observation.

[0042] The specific process is:

[0043] Step 101, constructing a satellite earth observation mission spatiotemporal grid data structure, which includes grid number, grid longitude and latitude, satellite code, access time, satellite payload type, satellite payload resolution, satellite payload working mode, satellite side swing angle and solar altitude angle; the grid data structure is as follows Figure 2 As shown;

[0044] Step 102, calculating satellite access information for all satellites participating in the multi-frequency earth observation mission, the calculation results include access time, satellite payload resolution, satellite payload working mode, satellite side swing angle and solar altitude angle.

[0045] Among them, the observation position refers to the geographical location where the satellite wants to observe the earth, which is composed of longitude and latitude data; the time period refers to the start time and end time when the geographical location is required to be observed; the number of times refers to the number of times the geographical location is required to be observed within the specified time; the resolution refers to the satellite payload resolution required to be observed at the geographical location within the specified time; the payload refers to the satellite payload type required to be observed at the geographical location within the specified time.

[0046] Step 103, storing satellite access information according to the grid geographical location to form a satellite earth observation space-time grid.

[0047] Step 2: Obtain observation frequency requirements, including observation location, time period, number of times, resolution, and load requirements;

[0048] Step 3: According to the observation location in the observation frequency requirement, i.e., the longitude and latitude information, the corresponding location is retrieved in the satellite earth observation space-time grid to obtain the relevant satellite earth observation space-time grid and the corresponding grid number.

[0049] Step 4: Obtain the access sequence information of the relevant satellites in the satellite earth observation space-time grid according to the requirements of time period, number of times, resolution and payload.

[0050] The specific process is:

[0051] Step 401, retrieve the access sequence information of the relevant satellites in the satellite earth observation space-time grid according to the logical order of time period, payload and resolution; the specific retrieval process is as follows: Figure 3 As shown, including:

[0052] Step 4011, obtaining all satellite access sequence information in the relevant satellite earth observation space-time grid, and filtering satellites according to the start time and end time required by the decomposition;

[0053] Step 4012, obtaining the satellite payload type within the time range;

[0054] Step 4013, determine whether the payload meets the decomposition requirements, if so, obtain the satellite payload resolution within the time range, otherwise delete the satellite and return to step 4012;

[0055] Step 4014, determine whether the resolution meets the requirement, if so, retain the satellite and its access information to the grid, otherwise delete the satellite and return to step 4012;

[0056] Step 4015, generating all satellites that meet the decomposition requirements and their access sequence information.

[0057] Step 402: If the satellite access times retrieved in step 401 are not less than the required observation frequency, proceed to the next step; if they are less than the required observation frequency, terminate the task and report an error.

[0058] Step 5, establishing a multi-frequency satellite earth observation evaluation function by integrating the time interval, satellite sway and the number of satellites;

[0059]

[0060] In the formula, represents the satellite earth observation evaluation function of the t-th multi-frequency combination, represents the satellite quantity adjustment coefficient, which is 500 in this embodiment. represents the number of satellites in the t-th multi-frequency combination, represents the satellite side swing angle adjustment coefficient, which is 120 in this embodiment. represents the roll angle corresponding to the jth observation of the i-th satellite of the t-th multi-frequency combination; represents the number of satellite observations of the t-th multi-frequency combination; represents the average observation interval of the t-th multi-frequency combination; The adjustment coefficient representing the average observation interval time is set to 60 in this embodiment.

[0061] Step 6: According to the observation frequency requirements, generate n observation arrangement schemes based on the access sequence information obtained in step 4 multiple times, and use the multi-frequency satellite earth observation evaluation function to obtain the evaluation value of each arrangement scheme, and select the optimal multi-frequency observation scheme; where n is the number of observation frequencies required for this decomposition.

[0062] The specific process is:

[0063] Step 601, in the satellite earth observation space-time grid, according to the observation frequency requirement, the satellite grid element task of n visits that meets the requirement is selected from the access sequence information obtained in step 4 as the task decomposition scheme; wherein n is the number of observation frequencies required for this decomposition;

[0064] Step 602, using a multi-frequency satellite earth observation evaluation function to calculate the evaluation value of this arrangement scheme;

[0065] Step 603, return to step 601, and compare the evaluation value calculated this time with the evaluation value calculated last time. If it is better than the evaluation value calculated last time, the arrangement scheme is retained, otherwise it is not retained.

[0066] Step 604, continue step 601 to step 603 until the evaluation value stops increasing or the number of iterations reaches an upper limit, and the optimal multi-frequency observation scheme is obtained; in this embodiment, the maximum number of iterations is 200.

Claims

1. A multi-frequency satellite earth observation task decomposition method based on space-time grid, characterized in that: The following steps are involved: Step 1: construct a space-time grid for satellite earth observation missions and calculate satellite access information; store the satellite access information according to the grid geographical location to form a space-time grid for satellite earth observation; Step 2: Obtain observation frequency requirements, including observation location, time period, number of times, resolution, and load requirements; Step 3, obtaining the relevant satellite earth observation space-time grid according to the observation position; Step 4, obtaining the access sequence information of the relevant satellites in the satellite earth observation space-time grid according to the time period, number of times, resolution and payload requirements; Step 5, establishing a multi-frequency satellite earth observation evaluation function by integrating the time interval, satellite sway and the number of satellites; Step 6: According to the observation frequency requirements, generate n observation arrangement schemes based on the access sequence information obtained in step 4 multiple times, and use the multi-frequency satellite earth observation evaluation function to obtain the evaluation value of each arrangement scheme, and select the optimal multi-frequency observation scheme; where n is the number of observation frequencies required for this decomposition.

2. The multi-frequency satellite earth observation task decomposition method based on space-time grid according to claim 1 is characterized in that: The specific process of step 1 is: Step 101, constructing a space-time grid data structure of a satellite earth observation mission, wherein the structure includes a grid number, grid longitude and latitude, satellite code, access time, satellite payload type, satellite payload resolution, satellite payload working mode, satellite side swing angle, and solar altitude angle; Step 102, calculating satellite access information for all satellites participating in the multi-frequency earth observation mission, the calculation results including access time, satellite payload resolution, satellite payload working mode, satellite side swing angle and solar altitude angle; Step 103, storing satellite access information according to the grid geographical location to form a satellite earth observation space-time grid.

3. The multi-frequency satellite earth observation task decomposition method based on space-time grid according to claim 1 is characterized in that: In the observation frequency requirement of step 2: the observation position refers to the geographical location that the satellite is to observe the earth, which is composed of latitude and longitude data; the time period refers to the start time and end time of the geographical location required to be observed; the number of times refers to the number of times the geographical location is required to be observed within the specified time; the resolution refers to the satellite payload resolution required to be observed at the geographical location within the specified time; Payload refers to the type of satellite payload that is required to be observed at the geographical location within a specified time.

4. The multi-frequency satellite earth observation task decomposition method based on space-time grid according to claim 1 is characterized in that: The specific process of step 3 is: According to the observation location in the observation frequency requirement, that is, the longitude and latitude information, the corresponding location is retrieved in the satellite earth observation space-time grid to obtain the corresponding grid number.

5. The multi-frequency satellite earth observation task decomposition method based on space-time grid according to claim 1 is characterized in that: The specific process of step 4 is as follows: Step 401, retrieving access sequence information of relevant satellites in the relevant satellite earth observation space-time grid according to the logical order of time period, payload and resolution; Step 402: If the satellite access times retrieved in step 401 are not less than the required observation frequency, proceed to the next step; if they are less than the required observation frequency, terminate the task and report an error.

6. The multi-frequency satellite earth observation task decomposition method based on space-time grid according to claim 1 is characterized in that: The multi-frequency satellite earth observation evaluation function established in step 5 is: ； In the formula, represents the satellite earth observation evaluation function of the t-th multi-frequency combination, represents the satellite quantity adjustment coefficient, represents the number of satellites in the t-th multi-frequency combination, represents the satellite side swing angle adjustment coefficient, represents the roll angle corresponding to the jth observation of the i-th satellite of the t-th multi-frequency combination; represents the number of satellite observations of the t-th multi-frequency combination; represents the average observation interval of the t-th multi-frequency combination; An adjustment factor that represents the average observation interval.

7. The method for decomposing multi-frequency satellite earth observation tasks based on time-space grid according to claim 6, characterized in that: The specific process of step 6 is as follows: Step 601, in the satellite earth observation space-time grid, according to the observation frequency requirement, the satellite grid element task of n visits that meets the requirement is selected from the access sequence information obtained in step 4 as the task decomposition solution; Where n is the number of observation frequencies required for this decomposition; Step 602, using a multi-frequency satellite earth observation evaluation function to calculate the evaluation value of this arrangement scheme; Step 603, return to step 601, and compare the evaluation value calculated this time with the evaluation value calculated last time. If it is better than the evaluation value calculated last time, the arrangement scheme is retained, otherwise it is not retained. Step 604, continue step 601 to step 603 until the evaluation value stops increasing or the number of iterations reaches an upper limit, and the optimal multi-frequency observation scheme is obtained.

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