Constellation design method comprehensively considering earth observation and limb detection coverage

Abstract

The invention provides a constellation design method comprehensively considering earth observation and limb detection coverage. The method comprises the steps that S10, the spatial position of each satellite is acquired; s20, performing grid division on the target area to obtain a plurality of grid points; s30, the visibility of each satellite to each grid point is judged, and the coverage multiple number of each grid point is obtained; s40, acquiring the coverage capability of the current constellation configuration in the target area under the current constellation parameters; s50, judging whether traversal of all constellation parameters under the current constellation configuration is completed or not, if so, turning to S60, and otherwise, repeating S10-S50 to traverse the next constellation parameter; and S60, judging whether traversal of all constellation configurations is completed or not, if so, obtaining an optimal constellation, and if not, repeating the steps S10-S60 to traverse the next constellation configuration. The technical problem that in the prior art, constellation design cannot meet the requirements for earth observation and limb detection coverage at the same time can be solved.

Description

Technical Field

[0001] The present invention relates to the technical field of constellation design, and in particular to a constellation design method that comprehensively considers earth observation and limb detection coverage. Background Art

[0002] In recent years, satellites have played an important role in agriculture, ocean, meteorology, national defense and other fields. Coverage is an important indicator to measure satellite performance. Due to the limited coverage of a single satellite, it is necessary to form a constellation of multiple satellites to improve the overall coverage. In addition to earth observation, tasks such as near-space target detection and starlight navigation also put forward requirements for the constellation's limb detection capabilities. Therefore, the design of the satellite constellation needs to consider indicators such as earth observation coverage and limb detection coverage at the same time.

[0003] In the existing technology, the constellation design method for earth observation coverage is relatively mature, and relevant design methods have also been proposed for the minimum constellation scale design under the satellite limb detection mode. However, there is a lack of optimal constellation design method that considers both earth observation coverage and limb detection coverage, and further in-depth research is still needed.

[0004] Therefore, given that the constellation design in the existing technology cannot simultaneously meet the requirements for both earth observation and limb detection coverage, it is necessary to develop an optimal constellation design method that comprehensively considers both earth observation and limb detection coverage. Summary of the invention

[0005] The present invention provides a constellation design method that comprehensively considers earth observation and limb detection coverage, which can solve the technical problem in the prior art that constellation design cannot simultaneously meet the requirements for earth observation and limb detection coverage.

[0006] According to one aspect of the present invention, a constellation design method that comprehensively considers earth observation and limb detection coverage is provided, the method comprising:

[0007] S10, acquiring the spatial position of each satellite based on the current constellation configuration and a constellation parameter in the current constellation configuration;

[0008] S20, gridding the target area to obtain a plurality of grid points; wherein the target area includes a ground observation area and an edge detection area;

[0009] S30, based on the spatial position of each satellite and the position of each grid point, determine the visibility of each satellite to each grid point, and obtain the coverage multiplicity of each grid point;

[0010] S40, obtaining the coverage capability of the target area of ​​the current constellation configuration under the current constellation parameters based on the coverage multiplicity of each grid point;

[0011] S50, determining whether the traversal of all constellation parameters under the current constellation configuration is completed, if so, going to S60, otherwise, repeating S10-S50 to traverse the next constellation parameter;

[0012] S60, judging whether the traversal of all constellation configurations is completed, if so, taking the constellation configuration and constellation parameters corresponding to the maximum coverage capacity of the target area in all traversal results as the optimal constellation, otherwise, repeating S10-S60 to traverse the next constellation configuration.

[0013] Preferably, acquiring the spatial position of each satellite based on the current constellation configuration and a constellation parameter in the current constellation configuration includes:

[0014] Assume that the current constellation is a Walker constellation, and the Walker constellation configuration is N / P / F, where N is the total number of satellites, P is the number of orbital planes, and F is the phase factor, F = 0, 1, ..., P-1;

[0015] Obtain the right ascension of the ascending node of each orbital plane in the constellation and the perigee argument of each satellite in each orbital plane in the constellation;

[0016] The longitude and latitude of each satellite are obtained based on the right ascension of the ascending node of each orbital plane in the constellation, the argument of perigee of each satellite in each orbital plane in the constellation, and the inclination of the satellite orbit;

[0017] The three-dimensional coordinates of each satellite in the earth's fixed system are obtained based on the longitude and latitude of each satellite and the orbital altitude of each satellite, thereby obtaining the spatial position of each satellite.

[0018] Preferably, the right ascension of the ascending node of each orbital plane in the constellation is obtained by the following formula:

[0019]

[0020] The perigee argument of each satellite in each orbital plane in the constellation is obtained by the following formula:

[0021]

[0022] The latitude and longitude of each satellite are obtained by the following formula:

[0023] latitude=sin -1 (sin(u)·sin(i));

[0024]

[0025] longitude=Ω+Δlongitude;

[0026] The three-dimensional coordinates of each satellite in the earth-fixed system are obtained by the following formula:

[0027] x=H·cos(latitude)·cos(longitude);

[0028] y=H·cos(latitude)·sin(longitude);

[0029] z = H sin(latitude);

[0030] Wherein, Ω is the right ascension of the ascending node of the lth orbital plane, Ω0 is the right ascension of the ascending node of the first orbital plane, u is the argument of perigee of the jth satellite in the lth orbital plane, u0 is the argument of perigee of the first satellite in the first orbital plane, latitude is the latitude of the satellite, i is the orbital inclination, mod(u,360) is the remainder obtained by dividing u by 360, Δlongitude is the difference between the longitude of the satellite and the right ascension of the ascending node, longitude is the longitude of the satellite, H is the orbital altitude of the satellite, x is the x-axis coordinate of the satellite in the earth-fixed system, y is the y-axis coordinate of the satellite in the earth-fixed system, and z is the z-axis coordinate of the satellite in the earth-fixed system.

[0031] Preferably, the target area is divided into grids to obtain a plurality of grid points including:

[0032] Divide the target area into equal intervals along the height direction;

[0033] Each altitude layer is gridded to obtain multiple grid points.

[0034] Preferably, gridding each altitude layer to obtain a plurality of grid points comprises: gridding each altitude layer using a division method with equal longitude and latitude intervals to obtain a plurality of grid points.

[0035] Preferably, gridding each altitude layer to obtain a plurality of grid points comprises: gridding each altitude layer using a grid division method with the same area to obtain a plurality of grid points.

[0036] Preferably, judging the visibility of each satellite to each grid point based on the spatial position of each satellite and the position of each grid point includes:

[0037] S31, judging whether the distance between the current satellite and the current grid point is less than the detection distance, if so, go to S32, otherwise, go to S35;

[0038] S32, judging whether the current grid point belongs to the earth observation area or the edge detection area, if the current grid point belongs to the earth observation area, go to S33, if the current grid point belongs to the edge detection area, go to S34;

[0039] S33, judging whether the field of view angle of the current grid point is smaller than the maximum field of view angle of the earth observation sensor, if so, the current grid point can be seen by the current satellite, otherwise, go to S35;

[0040] S34, determining whether the field of view angle of the current grid point is greater than the field of view angle corresponding to the lower edge of the field of view of the edge detection sensor, if so, the current grid point can be seen by the current satellite, otherwise, go to S35;

[0041] S35, the current grid point cannot be seen by the current satellite;

[0042] S36. Repeat S31-S35 until the traversal of all satellites and all grid points is completed.

[0043] Preferably, obtaining the coverage capability of the target area of ​​the current constellation configuration under the current constellation parameters based on the coverage multiplicity of each grid point includes:

[0044] Based on the coverage multiplicity of each grid point, obtain the m-layer coverage ratio of the target area of ​​the current constellation configuration under the current constellation parameters, where m=1, 2, ..., M, and M is the maximum coverage multiplicity;

[0045] The coverage capability of the target area of ​​the current constellation configuration under the current constellation parameters is obtained based on the m-layer coverage ratio of the target area.

[0046] Preferably, the coverage capability of the target area of ​​the current constellation configuration under the current constellation parameters is obtained by the following formula:

[0047]

[0048] Where cov is the coverage of the target area, percent_cov m is the m-fold coverage ratio of the target area, k m is the weight factor of the m-fold coverage ratio.

[0049] According to another aspect of the present invention, a computer device is provided, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements any of the above methods when executing the computer program.

[0050] By applying the technical solution of the present invention, the optimal constellation that meets the performance index is designed and selected, and the coverage requirements of earth observation and limb detection can be taken into account at the same time, and multiple coverage indexes such as coverage ratio and coverage multiplicity can be met, and the arbitrary coverage performance of the constellation can be met. Moreover, the relative weight can be adjusted according to the importance of earth observation and limb detection, so as to achieve the lowest constellation cost. The design method of the present invention is simple in calculation, small in computational complexity, and easy to implement. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] The included drawings are used to provide a further understanding of the embodiments of the present invention, which constitute a part of the specification, are used to illustrate the embodiments of the present invention, and together with the text description, explain the principles of the present invention. Obviously, the drawings in the following description are only some embodiments of the present invention, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0052] Figure 1 A flowchart of a constellation design method that comprehensively considers earth observation and limb detection coverage is shown according to an embodiment of the present invention;

[0053] Figure 2 A schematic diagram showing a grid division method provided according to an embodiment of the present invention is shown;

[0054] Figure 3 The figure shows the field of view range of the earth observation sensor and the limb detection sensor carried by a single satellite according to an embodiment of the present invention;

[0055] Figure 4a It shows a constellation-to-earth observation dual coverage ratio diagram obtained by STK simulation according to an embodiment of the present invention;

[0056] Figure 4b A diagram showing a constellation limb detection double coverage ratio obtained by STK simulation according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0057] It should be noted that, in the absence of conflict, the embodiments in this application and the features in the embodiments can be combined with each other. The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0058] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0059] Unless otherwise specifically stated, the relative arrangement of the parts and steps described in these embodiments, numerical expressions and numerical values ​​do not limit the scope of the present invention. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to the actual proportional relationship. The technology, method and equipment known to ordinary technicians in the relevant field may not be discussed in detail, but in appropriate cases, the technology, method and equipment should be regarded as a part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0060] like Figure 1 As shown, the present invention provides a constellation design method that comprehensively considers earth observation and limb detection coverage, and the method includes:

[0061] S10, acquiring the spatial position of each satellite based on the current constellation configuration and a constellation parameter in the current constellation configuration;

[0062] S20, gridding the target area to obtain a plurality of grid points; wherein the target area includes a ground observation area and an edge detection area;

[0063] S30, based on the spatial position of each satellite and the position of each grid point, determine the visibility of each satellite to each grid point, and obtain the coverage multiplicity of each grid point;

[0064] S40, obtaining the coverage capability of the target area of ​​the current constellation configuration under the current constellation parameters based on the coverage multiplicity of each grid point;

[0065] S50, determining whether the traversal of all constellation parameters under the current constellation configuration is completed, if so, going to S60, otherwise, repeating S10-S50 to traverse the next constellation parameter;

[0066] S60, judging whether the traversal of all constellation configurations is completed, if so, taking the constellation configuration and constellation parameters corresponding to the maximum coverage capacity of the target area in all traversal results as the optimal constellation, otherwise, repeating S10-S60 to traverse the next constellation configuration.

[0067] In the present invention, all constellation parameters refer to all constellation parameters within a preset constellation parameter range. Similarly, all constellation configurations refer to all constellation configurations within a preset constellation configuration range.

[0068] The present invention selects the optimal constellation that meets the performance index by design, can take into account the coverage requirements of earth observation and limb detection at the same time, meet the coverage ratio, coverage multiplicity and other coverage indexes, meet the arbitrary coverage performance of the constellation, and can adjust the relative weight according to the importance of earth observation and limb detection, so as to achieve the lowest constellation cost. The design method of the present invention is simple in calculation, small in computational complexity and easy to implement.

[0069] According to an embodiment of the present invention, in S10 of the present invention, acquiring the spatial position of each satellite based on the current constellation configuration and a constellation parameter in the current constellation configuration includes:

[0070] S11. Assume that the current constellation is a Walker constellation, and the Walker constellation configuration is N / P / F, where N is the total number of satellites, P is the number of orbital planes, and F is the phase factor, F=0, 1, ..., P-1;

[0071] S12, obtaining the right ascension of the ascending node of each orbital plane in the constellation and the argument of perigee of each satellite in each orbital plane in the constellation;

[0072] S13, obtaining the longitude and latitude of each satellite based on the right ascension of the ascending node of each orbital plane in the constellation, the argument of perigee of each satellite in each orbital plane in the constellation, and the inclination of the satellite orbit;

[0073] S14. Based on the longitude and latitude of each satellite and the orbital altitude of each satellite, the three-dimensional coordinates of each satellite in the earth fixed system are obtained, thereby obtaining the spatial position of each satellite.

[0074] Specifically, in S12 of the present invention, the right ascension of the ascending node of each orbital plane in the constellation is obtained by the following formula:

[0075]

[0076] In S12 of the present invention, the perigee argument of each satellite in each orbital plane in the constellation is obtained by the following formula:

[0077]

[0078] In S13 of the present invention, the longitude and latitude of each satellite are obtained by the following formula:

[0079] latitude=sin -1 (sin(u)·sin(i));

[0080]

[0081] longitude=Ω+Δlongitude;

[0082] In S14 of the present invention, the three-dimensional coordinates of each satellite in the earth fixed system are obtained by the following formula:

[0083] x=H·cos(latitude)·cos(longitude);

[0084] y=H·cos(latitude)·sin(longitude);

[0085] z = H sin(latitude);

[0086] Wherein, Ω is the right ascension of the ascending node of the lth orbital plane, Ω0 is the right ascension of the ascending node of the first orbital plane, u is the argument of perigee of the jth satellite in the lth orbital plane, u0 is the argument of perigee of the first satellite in the first orbital plane, latitude is the latitude of the satellite, i is the orbital inclination, mod(u,360) is the remainder obtained by dividing u by 360, Δlongitude is the difference between the longitude of the satellite and the right ascension of the ascending node, longitude is the longitude of the satellite, H is the orbital altitude of the satellite, x is the x-axis coordinate of the satellite in the earth-fixed system, y is the y-axis coordinate of the satellite in the earth-fixed system, and z is the z-axis coordinate of the satellite in the earth-fixed system.

[0087] In this embodiment, the constellation configuration is pre-set, and the spatial position of each satellite can also be set manually.

[0088] According to an embodiment of the present invention, in S20 of the present invention, the target area is gridded to obtain a plurality of grid points including:

[0089] S21, dividing the target area into equal intervals along the height direction;

[0090] S22, grid each altitude layer to obtain multiple grid points, such as Figure 2 shown.

[0091] Specifically, in S22 of the present invention, gridding each altitude layer to obtain a plurality of grid points includes: gridding each altitude layer using a division method with equal longitude and latitude intervals to obtain a plurality of grid points.

[0092] Specifically, in S22 of the present invention, gridding each altitude layer to obtain a plurality of grid points includes: gridding each altitude layer using a grid division method with the same area to obtain a plurality of grid points.

[0093] In this embodiment, the target area may be a global area or a local area; STK may be used to generate the grid.

[0094] According to an embodiment of the present invention, in S30 of the present invention, judging the visibility of each satellite to each grid point based on the spatial position of each satellite and the position of each grid point includes:

[0095] S31, judging whether the distance between the current satellite and the current grid point is less than the detection distance, if so, go to S32, otherwise, go to S35;

[0096] S32, judging whether the current grid point belongs to the earth observation area or the edge detection area, if the current grid point belongs to the earth observation area, go to S33, if the current grid point belongs to the edge detection area, go to S34;

[0097] S33, judging whether the field of view angle of the current grid point is smaller than the maximum field of view angle of the earth observation sensor, if so, the current grid point can be seen by the current satellite, otherwise, go to S35;

[0098] S34, determining whether the field of view angle of the current grid point is greater than the field of view angle corresponding to the lower edge of the field of view of the edge detection sensor, if so, the current grid point can be seen by the current satellite, otherwise, go to S35;

[0099] S35, the current grid point cannot be seen by the current satellite;

[0100] S36. Repeat S31-S35 until the traversal of all satellites and all grid points is completed.

[0101] In this embodiment, each satellite carries both an earth observation sensor and a limb detection sensor, with a field of view of Figure 3 shown.

[0102] Specifically, in S31 of the present invention, the maximum detection distance d1 of the earth observation sensor can be set to 4000 km, and the maximum detection distance d2 of the edge detection sensor can be set to 6000 km;

[0103] In S33 of the present invention, the viewing angle of the grid point is obtained by the following formula:

[0104]

[0105] In S33 of the present invention, the maximum field of view angle of the earth observation sensor is obtained by the following formula:

[0106] α1=sin -1 ((Re+H1) / (Re+H));

[0107] In S34 of the present invention, the field of view angle corresponding to the lower edge of the field of view of the edge detection sensor is obtained by the following formula:

[0108] α2=sin -1(Re / (Re+H));

[0109] Where α is the field of view angle of the grid point, dot represents the dot product, norm represents the Euclidean norm, (x1, y1, z1) represents the coordinates of the grid point, (x2, y2, z2) represents the coordinates of the satellite, α1 is the maximum field of view angle of the earth observation sensor, Re is the radius of the earth, H1 is the maximum height of the earth observation target, H is the orbital height of the satellite, and α2 is the field of view angle corresponding to the lower edge of the field of view of the limb detection sensor.

[0110] According to an embodiment of the present invention, in S40 of the present invention, obtaining the coverage capability of the target area of ​​the current constellation configuration under the current constellation parameters based on the coverage multiplicity of each grid point includes:

[0111] S41. Obtaining the m-layer coverage ratio of the target area of ​​the current constellation configuration under the current constellation parameters based on the coverage multiplicity of each grid point; wherein m=1, 2, ..., M, M is the maximum coverage multiplicity, the coverage multiplicity is the number of visible satellites, and the m-layer coverage ratio is the proportion of grid points with a coverage multiplicity greater than or equal to m;

[0112] S42. Obtaining the coverage capability of the target area of ​​the current constellation configuration under the current constellation parameters based on the m-fold coverage ratio of the target area.

[0113] Specifically, in S41 of the present invention, the m-fold coverage ratio of the target area may be the m-fold coverage ratio of the entire target area, or may be the m-fold coverage ratio of a specific height of the target area.

[0114] In S42 of the present invention, the coverage capability of the target area of ​​the current constellation configuration under the current constellation parameters is obtained by the following formula:

[0115]

[0116] Where cov is the coverage of the target area, percent_cov m is the m-fold coverage ratio of the target area, k m is the weight factor of the m-fold coverage ratio.

[0117] In this embodiment, different tasks have different requirements for earth observation and limb detection coverage capabilities, that is, different requirements for the m-fold coverage ratio of the constellation. The present invention calculates the comprehensive coverage capability by adjusting the weight factor of the m-fold coverage ratio, thereby maximizing cov to achieve the task requirements.

[0118] In order to further understand the present invention, the following Figure 1 - Figure 4 illustrates the constellation design method of the present invention in detail.

[0119] In the present embodiment, the target height of earth observation is set to 0-250km, and the target height of edge detection is 80-2000km. The objective function selected is the minimum earth observation double coverage ratio percent_cov2(ground) for all altitude surfaces and the minimum edge detection double coverage ratio percent_cov2(space) for all altitude surfaces. Assume that the constellation configuration is the Walker constellation, the satellite altitude range is 500-2000km, the inclination range is 60-90 °, the orbital plane number range is 3-5, the number of satellites in the orbital plane ranges from 6-10, and the phase factor range is 0-2. Because the method is fast in calculation speed, therefore in the present embodiment, percent_cov2(ground) and percent_cov2(space) under each group of parameters are calculated by the method of traversing parameters, and specific optimization method is not adopted. It should be noted that although the present embodiment does not use optimization algorithm, the method of the present invention is applicable to common multi-objective (and single-objective) optimization algorithm.

[0120] Table 1 shows the constellation parameters with the largest sum of weights such as percent_cov2(ground) and percent_cov2(space) when the total number of satellites is fixed. The optimal constellation parameters are selected based on this table, that is, the constellation parameters with the largest coverage capability are selected. Furthermore, in order to reduce costs, the constellation parameters with the least number of satellites can be selected according to different indicator requirements.

[0121] Table 1

[0122]

[0123] According to different index requirements, the constellation parameters with the least number of satellites are selected. Figure 4 shows the dual coverage ratio of the 32 / 4 / 1 constellation in Table 1 for the earth observation at an altitude of 0 km and the dual coverage ratio of the limb detection at an altitude of 80 km calculated by STK simulation. The simulation results are close to the calculation results (84.5%, 90.7%) of the method of the present invention, which shows the accuracy of the design method of the present invention.

[0124] The present invention also provides a computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements any of the above methods when executing the computer program.

[0125] In summary, the present invention provides a constellation design method that comprehensively considers the coverage of earth observation and limb detection. By designing and selecting the optimal constellation that meets the performance index, it is possible to simultaneously take into account the coverage requirements of earth observation and limb detection, meet multiple coverage indicators such as coverage ratio and coverage multiplicity, meet the arbitrary coverage performance of the constellation, and adjust the relative weights according to the importance of earth observation and limb detection to achieve the lowest constellation cost. The design method of the present invention is simple in calculation, small in computational complexity, and easy to implement.

[0126] Parts of the present invention that are not described in detail are well known to those skilled in the art.

[0127] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the devices or elements referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention. The directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0128] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0129] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0130] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A constellation design method that comprehensively considers earth observation and limb detection coverage, characterized in that: The method comprises: S10, acquiring the spatial position of each satellite based on the current constellation configuration and a constellation parameter in the current constellation configuration; S20, gridding the target area to obtain a plurality of grid points; wherein the target area includes a ground observation area and an edge detection area; S30, based on the spatial position of each satellite and the position of each grid point, determine the visibility of each satellite to each grid point, and obtain the coverage multiplicity of each grid point; S40, obtaining the coverage capability of the target area of ​​the current constellation configuration under the current constellation parameters based on the coverage multiplicity of each grid point; S50, determining whether the traversal of all constellation parameters under the current constellation configuration is completed, if so, going to S60, otherwise, repeating S10-S50 to traverse the next constellation parameter; S60, judging whether the traversal of all constellation configurations is completed, if so, taking the constellation configuration and constellation parameters corresponding to the maximum coverage capacity of the target area in all traversal results as the optimal constellation, otherwise, repeating S10-S60 to traverse the next constellation configuration.

2. The method according to claim 1, characterized in that Obtaining the spatial position of each satellite based on the current constellation configuration and a constellation parameter in the current constellation configuration includes: Assume that the current constellation is a Walker constellation, and the Walker constellation configuration is N / P / F, where N is the total number of satellites, P is the number of orbital planes, and F is the phase factor, F = 0, 1, ..., P-1; Obtain the right ascension of the ascending node of each orbital plane in the constellation and the perigee argument of each satellite in each orbital plane in the constellation; The longitude and latitude of each satellite are obtained based on the right ascension of the ascending node of each orbital plane in the constellation, the argument of perigee of each satellite in each orbital plane in the constellation, and the inclination of the satellite orbit; The three-dimensional coordinates of each satellite in the earth's fixed system are obtained based on the longitude and latitude of each satellite and the orbital altitude of each satellite, thereby obtaining the spatial position of each satellite.

3. The method according to claim 1 or 2, characterized in that: The right ascension of the ascending node of each orbital plane in the constellation is obtained by the following formula: The perigee argument of each satellite in each orbital plane in the constellation is obtained by the following formula: The latitude and longitude of each satellite are obtained by the following formula: latitude=sin -1 (sin(u)·sin(i)); longitude=Ω+Δlongitude; The three-dimensional coordinates of each satellite in the earth-fixed system are obtained by the following formula: x=H·cos(latitude)·cos(longitude); y=H·cos(latitude)·sin(longitude); z = H sin(latitude); Wherein, Ω is the right ascension of the ascending node of the lth orbital plane, Ω0 is the right ascension of the ascending node of the first orbital plane, u is the argument of perigee of the jth satellite in the lth orbital plane, u0 is the argument of perigee of the first satellite in the first orbital plane, latitude is the latitude of the satellite, i is the orbital inclination, mod(u,360) is the remainder obtained by dividing u by 360, Δlongitude is the difference between the longitude of the satellite and the right ascension of the ascending node, longitude is the longitude of the satellite, H is the orbital altitude of the satellite, x is the x-axis coordinate of the satellite in the earth-fixed system, y is the y-axis coordinate of the satellite in the earth-fixed system, and z is the z-axis coordinate of the satellite in the earth-fixed system.

4. The method according to claim 1, characterized in that: The target area is meshed to obtain multiple mesh points including: Divide the target area into equal intervals along the height direction; Each altitude layer is gridded to obtain multiple grid points.

5. The method according to claim 4, characterized in that Dividing each altitude layer into grids to obtain a plurality of grid points includes: dividing each altitude layer into grids using a division method with equal longitude and latitude intervals to obtain a plurality of grid points.

6. The method according to claim 4, characterized in that Dividing each altitude layer into a grid to obtain a plurality of grid points includes: dividing each altitude layer into a grid using a division method with the same grid area to obtain a plurality of grid points.

7. The method according to claim 1, characterized in that Determining the visibility of each satellite to each grid point based on the spatial position of each satellite and the position of each grid point includes: S31, judging whether the distance between the current satellite and the current grid point is less than the detection distance, if so, go to S32, otherwise, go to S35; S32, judging whether the current grid point belongs to the earth observation area or the edge detection area, if the current grid point belongs to the earth observation area, go to S33, if the current grid point belongs to the edge detection area, go to S34; S33, judging whether the field of view angle of the current grid point is smaller than the maximum field of view angle of the earth observation sensor, if so, the current grid point can be seen by the current satellite, otherwise, go to S35; S34, determining whether the field of view angle of the current grid point is greater than the field of view angle corresponding to the lower edge of the field of view of the edge detection sensor, if so, the current grid point can be seen by the current satellite, otherwise, go to S35; S35, the current grid point cannot be seen by the current satellite; S36. Repeat S31-S35 until the traversal of all satellites and all grid points is completed.

8. The method according to claim 1, characterized in that: The coverage capability of the target area of ​​the current constellation configuration under the current constellation parameters is obtained based on the coverage multiplicity of each grid point, including: Based on the coverage multiplicity of each grid point, obtain the m-layer coverage ratio of the target area of ​​the current constellation configuration under the current constellation parameters, where m=1, 2, ..., M, and M is the maximum coverage multiplicity; The coverage capability of the target area of ​​the current constellation configuration under the current constellation parameters is obtained based on the m-fold coverage ratio of the target area.

9. The method according to claim 8, characterized in that The coverage capability of the target area of ​​the current constellation configuration under the current constellation parameters is obtained by the following formula: Where cov is the coverage of the target area, percent_cov m is the m-fold coverage ratio of the target area, k m is the weight factor of the m-fold coverage ratio.

10. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the method according to any one of claims 1 to 9 is implemented.

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