Multi-satellite collaborative observation probability estimation method for window type target

Abstract

The invention relates to a multi-satellite collaborative observation probability estimation method for a window type target. The method comprises the following steps: inputting a statistical time range, an orbital element number and a load observation range of a guiding constellation A, and an orbital element number and a load observation range of a guided constellation B; and determining a to-be-observed area O, based on whether the constellation A is a geostationary orbit satellite, calculating the collaborative observation probability that the constellation A guides the low-orbit constellation B, and outputting a collaborative observation probability result. According to the method, the defect that the time dynamic characteristics of the window type target are not fully considered when the collaborative observation probability of the satellite to the land target is analyzed in the existing method is overcome, and the problem that the window type target collaborative observation success probability is inaccurately estimated in the existing method is solved.

Description

Technical Field

[0001] This invention relates to the field of multi-satellite collaborative observation technology, and in particular to a multi-satellite collaborative observation probability estimation method for window-type targets. Background Technology

[0002] Collaborative observation of land targets by remote sensing satellites has significant application value in fields such as resource surveys, environmental monitoring, and disaster assessment. Multi-satellite collaborative observation, as an important direction in the development of remote sensing technology, enables rapid coverage searching, high-precision observation, and multi-dimensional data fusion of large-scale land targets through the coordinated work of multiple remote sensing satellites, thereby significantly improving the efficiency and data quality of remote sensing missions. For example, in natural resource protection, multi-satellite collaborative observation can detect and issue early warnings of illegal logging and mining activities targeting forests and mineral resources; in environmental monitoring, collaborative observation technology can effectively identify and track dynamic targets such as pollution sources and vegetation changes; and in disaster assessment, multi-satellite collaborative observation can quickly acquire image data of disaster areas, providing decision support for rescue operations.

[0003] Existing multi-satellite collaborative observation probability analysis methods mostly analyze from the perspective of target revisit from satellite orbits. These methods often treat the observed target as static or quasi-static, providing the revisit probability of multiple satellites over a specified area. However, land-based window targets typically exhibit characteristics such as random appearance times and limited dwell times. For example, land-based illegal mining and logging convoys are a type of window target; they may appear randomly within a certain time period and quickly take measures such as relocation and concealment after the illegal mining or logging operations end, changing the form and state of related vehicles and equipment to evade search. For instance, in the prior art, Chinese invention patent publication number CN112945241A provides a satellite orbit evaluation method based on observation windows and tracking arcs, but it mainly targets reconnaissance windows in fixed areas and does not consider the dynamic characteristics of the target. While CN118239008A proposes a large-scale heterogeneous constellation continuous observation control method, its focus is on task allocation and trajectory prediction, without involving probability modeling of randomly appearing targets. Chinese invention patent with publication number CN113722897A involves high-resolution satellite collaborative observation, but it focuses on orbit prediction and station collaboration, lacking modeling of the target's temporal dynamic characteristics. Although Chinese invention patent with publication number CN119374562A considers continuous observation task scheduling, it still takes fixed targets or regions as objects and does not break through the premise of "static targets".

[0004] It is evident that existing multi-satellite collaborative observation probability estimation methods for static targets only analyze fixed regions or fixed targets, and do not model and analyze the revisit observation problem of window-type targets that appear randomly and have complex dynamic characteristics. Therefore, they are difficult to accurately characterize the collaborative observation probability of constellations on window-type targets, and there is still a certain gap between them and the needs of actual evaluation applications. Summary of the Invention

[0005] To address the technical problems existing in the prior art, the present invention aims to provide a multi-satellite collaborative observation probability estimation method for window-type targets, thereby solving the problem that existing methods are inaccurate in estimating the collaborative observation probability of randomly occurring and dynamically complex window-type targets.

[0006] To achieve the above-mentioned objectives, this invention provides a multi-satellite cooperative observation probability estimation method for window-type targets, comprising the following steps:

[0007] Step S1: Input the statistical time range, the orbital elements and payload observation range of the guiding constellation A, and the orbital elements and payload observation range of the guided constellation B;

[0008] Step S2: Determine the observation area O and determine whether constellation A is a geostationary orbit satellite. If yes, proceed with steps S3 and S4 in sequence. If no, proceed with steps S5 and S6 in sequence.

[0009] Step S3: If constellation A is not a geostationary orbit satellite, then calculate the set of observation windows for constellations A and B for region O;

[0010] Step S4: Based on the observation window set, simulate the target appearance time using a sliding window, and calculate the probability of coordinated observation of the window-type target by constellation A guiding constellation B.

[0011] Step S5: If constellation A is a geostationary orbit satellite, then calculate the set of observation windows of constellation B for region O;

[0012] Step S6: Based on the observation window set, calculate the cooperative observation probability of constellation A guiding low-Earth orbit constellation B through a sliding window and Bayesian conditional probability.

[0013] Step S7: Output the collaborative observation probability results.

[0014] According to one technical solution of the present invention, step S3 specifically includes:

[0015] Based on the orbital elements of constellations A and B and the position of the region O to be observed, the set of observation windows for constellation A over the statistical time period is obtained. ,in, For the number of observation windows, This represents the time corresponding to the left endpoint of the i-th observation window interval. This represents the time corresponding to the right endpoint of the i-th observation window interval;

[0016] Similarly, calculate the set of observation windows of constellation B over region O within the statistical time frame. ,in, For the number of observation windows, This represents the time corresponding to the left endpoint of the i-th observation window interval. This represents the time corresponding to the right endpoint of the i-th observation window interval.

[0017] According to one technical solution of the present invention, step S4 specifically includes:

[0018] Step S401: Input the observation window set of constellation A and constellation B for region O. and ;

[0019] Step S402: Set the dwell time of a window-type target to a constant. Set the time for the target dwell window to slide to the right on the timeline in each iteration to . Set the constellation-based collaborative guidance preparation time to a constant. This represents the total time from when satellite A of constellation begins observing region O to when satellite B of constellation receives guidance information and completes mission preparation;

[0020] Step S403: Initialize the current time as The target's dwell time window at the current moment for Initialize the total number of target resident windows. The number of times constellation A successfully observed the target was: The number of times that constellation A and constellation B successfully completed coordinated observations of the target is: ;

[0021] Step S404: Determine the target's dwell time window at the current moment. Has the end time been exceeded? , is represented as: ;

[0022] If the inequality is true, proceed to step S411; if it is true, proceed to step S405.

[0023] Step S405, Total number of target resident windows ;

[0024] Step S406: Traverse the observation window set of constellation A Determine the target's dwell time window at the current moment. Does it contain an observation window? That is, satisfying and ;

[0025] If the conditions are met, the observation window of constellation A can successfully observe the target, and then proceed to step S407; if the conditions are not met, the observation is considered to have failed, and then proceed to step S410.

[0026] Step S407: The number of times constellation A successfully observed the target is... ;

[0027] Step S408: Determine the target's dwell time window at the current moment. Does the data contain observation windows for constellation A and constellation B that meet the requirements for successful collaborative observation? If yes, proceed to step S409; otherwise, proceed to step S410.

[0028] Step S409, the number of times constellation A and constellation B successfully completed collaborative observation of the target. ;

[0029] Step S410, Time Slide the target dwell time window to the right. Target dwell time window Represented as ;

[0030] Repeat steps S404 to S410 until the target dwell time window exceeds the end time. Then proceed to step S411;

[0031] Step S411: Successful coordinated observation of a window-shaped target within region O by constellations A and B is recorded as an event. Its probability is expressed as: ;

[0032] Step S412: According to Bayes' theorem, after constellation A successfully searches and observes the target, the probability of guiding constellation B to successfully observe it is expressed as:

[0033]

[0034] Among them, the event The successful coordinated observation of a window-shaped target within region O by constellations A and B is recorded as an event; Constellation A successfully searched for and observed window-shaped targets within region O.

[0035] According to a technical solution of the present invention, step S6 specifically includes:

[0036] Step S601: Input the observation window set of constellation B for region O. ;

[0037] Step S602: Set the dwell time of the window-type target to a constant. Set the time for the target dwell window to slide to the right on the timeline in each iteration to . Set the preparation time for inter-constellation collaborative guidance to a constant. This represents the total time from when satellite A of constellation begins observing region O to when satellite B receives guidance information and completes mission preparation;

[0038] Step S603: Initialize the current time as The target's dwell time window at the current moment for Initialize the total number of target resident windows. ;

[0039] Step S604: Determine the target's dwell time window at the current moment. Has the end time been exceeded? , is represented as: ;

[0040] If the inequality is true, proceed to step S608; if it is true, proceed to step S605.

[0041] Step S605, Total number of target resident windows ;

[0042] Step S606: Calculate the current target dwell time window. The conditional probability that constellation A successfully observes the target and then guides constellation B to successfully observe the target.

[0043] Step S607, Time Slide the target dwell time window to the right. Target dwell time window Represented as ;

[0044] Repeat steps S604 to S607 until the target dwell time window exceeds the end time. Then proceed to step S608;

[0045] Step S608: Based on the conditional probability at each time point Among them, the event For the successful coordinated observation of window-shaped targets within region O by constellations A and B, the event... For constellation A to successfully observe a window-shaped target within region O, event This indicates the current target dwell time window is... According to Bayes' theorem, after constellation A successfully searches for and observes the target, the probability that constellation B will successfully observe the window-shaped target within region O is expressed as:

[0046] in, The total number of target dwell windows is obtained by cyclically accumulating in step S605; since the target dwell windows slide uniformly over time, the events... The probability follows a uniform distribution. .

[0047] According to a technical solution of the present invention, in step S6, an event is defined. This indicates the current target dwell time window is... ;event Successful coordinated observation of window-shaped targets within region O by constellations A and B; event The observation window for constellation B is included in the target dwell time window at the current moment. Inside; then in the event and events Below, the event The conditional probability of occurrence is expressed as:

[0048]

[0049] in, In the formula The i-th observation window corresponding to constellation B satellites The left endpoint time, this observation window is within the target dwell time window at time k; To guide preparation time ; The duration for which a window-type target remains in the window.

[0050] Compared with the prior art, the present invention has the following advantages:

[0051] This invention proposes a multi-satellite collaborative observation probability estimation method for window-type targets. By introducing a sliding window mechanism to simulate the temporal characteristics of random target appearance and combining it with guidance preparation time constraints, a collaborative observation probability model that better matches the actual dynamic target characteristics is established. This solves the problem of poor applicability of traditional static target probability estimation methods to window-type targets, and significantly improves the estimation accuracy.

[0052] This invention proposes differentiated calculation methods based on sliding window counting and Bayesian conditional probability for two typical collaborative scenarios: high-orbit guidance of low-orbit and medium-low-orbit guidance of low-orbit. These methods enable the model to adapt to the continuous coverage characteristics of high-orbit satellites and handle the constraints of intermittent observations from medium-low-orbit satellites, thereby enhancing the engineering applicability of the method.

[0053] This invention provides a reliable decision-making basis for multi-satellite mission planning systems by outputting quantitative collaborative observation probabilities. It supports users in evaluating the success rate of collaborative observations under different constellation combinations and time windows, thereby optimizing sensor scheduling strategies and improving the probability of capturing window-type targets.

[0054] The multi-satellite collaborative observation probability estimation method of this invention has low computational complexity, can be embedded into existing satellite mission planning systems, and supports rapid evaluation over large-scale constellations and long time periods. Furthermore, the model structure is open, allowing for the integration of more constraints (such as cloud cover, resolution, signal-to-noise ratio, etc.), thus enhancing scalability.

[0055] This invention can be used not only for pre-mission planning but also for post-mission performance evaluation. By comparing the actual observation success rate with the predicted probability, it can inversely evaluate the constellation's collaborative performance and the effectiveness of its guidance mechanism, providing data support for constellation optimization design. Attached Figure Description

[0056] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly described below. Obviously, the drawings described below are merely some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without creative effort.

[0057] Figure 1 This diagram illustrates a flowchart of a multi-satellite collaborative observation probability estimation method for window-type targets according to an embodiment of the present invention.

[0058] Figure 2 This invention relates to the calculation process for the cooperative observation probability of a low-Earth orbit constellation A satellite guiding a low-Earth orbit constellation B satellite;

[0059] Figure 3 The present invention relates to a schematic diagram of the observation time windows of constellation A and constellation B for successful coordinated observation, wherein A is a medium- and low-Earth orbit satellite constellation;

[0060] Figure 4 This invention relates to the calculation process for the cooperative observation probability of constellation A satellite guiding low-Earth orbit constellation B satellite;

[0061] Figure 5 The present invention relates to a schematic diagram of the observation time window for constellation A and constellation B to meet the requirements of successful coordinated observation, wherein A is a high-orbit satellite constellation. Detailed Implementation

[0062] The description of the embodiments in this specification should be taken in conjunction with the accompanying drawings, which should form part of the complete specification. In the drawings, the shape or thickness of the embodiments may be exaggerated and may be indicated in a simplified or convenient manner. Furthermore, parts of the various structures in the drawings will be described separately; it is worth noting that elements not shown in the figures or not described in words are in a form known to those skilled in the art.

[0063] The descriptions of the embodiments herein, including any references to directions and orientations, are for ease of description only and should not be construed as limiting the scope of the invention. The following description of preferred embodiments involves combinations of features, which may exist independently or in combination; the invention is not particularly limited to the preferred embodiments. The scope of the invention is defined by the claims.

[0064] The embodiments of this application mainly discuss the probability of multiple satellites collaboratively observing a single window-shaped target that randomly appears within a region. Let the preceding guiding remote sensing satellite constellation be A. Satellites in constellation A can search the region, but due to low resolution, they cannot accurately identify targets. The guided satellite constellation is B. Satellites in constellation B can perform high-resolution verification of a specific target location within the region. Satellites in constellation B are typically low-Earth orbit (LEO) satellites. It is assumed that all satellites within constellation A are identical; satellites within constellation B are also identical. When A is a high-Earth orbit (HEO) remote sensing satellite, only the case where constellation A consists of one satellite is discussed.

[0065] like Figures 1 to 5 As shown, the present invention provides a multi-satellite cooperative observation probability estimation method for window-type targets, comprising the following steps:

[0066] Step S1: Input the statistical time range, the orbital elements and payload observation range of the guiding constellation A, and the orbital elements and payload observation range of the guided constellation B;

[0067] The input statistical time range is denoted as . The start time is denoted as 0, and the end time is denoted as... .

[0068] Step S2: Determine the observation area O and determine whether constellation A is a geostationary orbit satellite. If yes, proceed with steps S3 and S4 in sequence. If no, proceed with steps S5 and S6 in sequence.

[0069] Determine the size of the rectangular observation area O, input the latitude and longitude positions of the four vertices of the observation area O, and the area of ​​the observation area should not exceed the maximum observable range of the satellites in the guided constellation B.

[0070] Determine whether the satellites in the input constellation A are geostationary orbit (GEO) satellites. If not, proceed with steps S3 and S4 in sequence to calculate the probability of collaborative observation between low-Earth orbit or medium-low Earth orbit satellite constellations.

[0071] If so, then the satellites of constellation A are high-orbit remote sensing satellites, and it is further determined whether the area to be observed, O, is within the observable range of a single satellite in constellation A.

[0072] If the area to be observed is within the observable range of a single satellite in constellation A, then proceed with steps S5 and S6 in sequence to calculate the probability of collaborative observation between high and low orbit constellations; otherwise, proceed with step S7 in sequence to determine that collaborative observation is not possible and end the process.

[0073] Step S3: If constellation A is not a geostationary orbit satellite, then calculate the set of observation windows for region O for constellations A and B, specifically including:

[0074] Based on the orbital elements of constellations A and B and the location of the region O to be observed, and using existing orbital access calculation methods, the set of observation windows for constellation A over the statistical time frame can be obtained. ,in, For the number of observation windows, This represents the time corresponding to the left endpoint of the i-th observation window interval. This represents the time corresponding to the right endpoint of the i-th observation window interval. The orbital access calculation method used is numerical simulation, that is, using the STK simulation tool, by establishing a constellation six-root number orbital model and a corresponding sensor model, inputting the area to be observed, calculating the constellation's access to the area, and obtaining the constellation's observation window for the area. It is understood that other existing methods can also be used for orbital access calculation, which will not be described in detail here.

[0075] Similarly, we can obtain the set of observation windows of constellation B for region O within the statistical time range. ,in, For the number of observation windows, This represents the time corresponding to the left endpoint of the i-th observation window interval. This represents the time corresponding to the right endpoint of the i-th observation window interval.

[0076] Step S4: Based on the observation window set obtained in step S3, simulate the target appearance time using a sliding window, and calculate the cooperative observation probability of constellation A guiding constellation B for the window-type target, such as... Figure 2 As shown, it specifically includes:

[0077] Step S401: Input the observation window set of constellation A and constellation B for region O. and ;

[0078] Step S402: Set the dwell time of a window-type target to a constant. Set the time for the target dwell window to slide to the right on the timeline in each iteration to . Set the constellation-based collaborative guidance preparation time to a constant. This represents the total time from when satellite A of constellation begins observing region O to when satellite B of constellation receives guidance information and completes mission preparation;

[0079] Step S403: Initialize the current time as The target's dwell time window at the current moment for Initialize the total number of target resident windows. The number of times constellation A successfully observed the target was: The number of times that constellation A and constellation B successfully completed coordinated observations of the target is: ;

[0080] Step S404: Determine the target's dwell time window at the current moment. Has the end time been exceeded? , is represented as: ;

[0081] If the inequality is true, proceed to step S411; if it is true, proceed to step S405.

[0082] Step S405, Total number of target resident windows ;

[0083] Step S406: Traverse the observation window set of constellation A Determine the target's dwell time window at the current moment. Does it contain an observation window? That is, satisfying and ;

[0084] If the conditions are met, the observation window of constellation A can successfully observe the target, and then proceed to step S407; if the conditions are not met, the observation is considered to have failed, and then proceed to step S410.

[0085] Step S407: The number of times constellation A successfully observed the target is... ;

[0086] Step S408: Determine the target's dwell time window at the current moment. Does the data contain observation windows for constellation A and constellation B that meet the requirements for successful collaborative observation? If yes, proceed to step S409; otherwise, proceed to step S410.

[0087] The schematic diagram of the observation windows of constellation A and constellation B that satisfy successful coordinated observation is shown below. Figure 3 As shown. By Figure 3 It can be seen that, For constellations A and B to complete coordinated observation of the target at a given moment, the following two conditions must be met simultaneously:

[0088] ① The observation windows for both constellation A and constellation B are within the target's current residence time window. Inside;

[0089] ② The time interval from when observations begin on satellite A of constellation A to when observations begin on satellite B of constellation B, which is being guided. It should be greater than or equal to the guidance preparation time. .

[0090] Step S409, the number of times constellation A and constellation B successfully completed collaborative observation of the target. ;

[0091] Step S410, Time Slide the target dwell time window to the right. Target dwell time window Represented as ;

[0092] Repeat steps S404 to S410 until the target dwell time window exceeds the end time. Then proceed to step S411;

[0093] Step S411: Successful coordinated observation of a window-shaped target within region O by constellations A and B is recorded as an event. Its probability is expressed as: ;

[0094] Step S412: According to Bayes' theorem, after constellation A successfully searches and observes the target, the probability of guiding constellation B to successfully observe it is expressed as:

[0095]

[0096] Among them, the event The successful coordinated observation of a window-shaped target within region O by constellations A and B is recorded as an event; Constellation A successfully searched for and observed window-shaped targets within region O.

[0097] When the satellites of constellation A are in GEO orbit, they can observe region O at any time. The following describes the method for calculating the probability of coordinated observation between constellation A and constellation B in this case, in conjunction with steps S5 and S6.

[0098] Step S5: If constellation A is a geostationary orbit satellite, then calculate the set of observation windows of constellation B for region O;

[0099] Based on the orbital elements of constellation B and the location of the region O to be observed, similarly following step S3, the set of observation windows for constellation B over the statistical time frame can be obtained. ,in, For the number of observation windows, This represents the time corresponding to the left endpoint of the i-th observation window interval. This represents the time corresponding to the right endpoint of the i-th observation window interval.

[0100] When constellation A consists of geostationary orbit satellites, it is a high-orbit satellite.

[0101] Step S6: Based on the observation window set obtained in step S5, calculate the cooperative observation probability of high-Earth orbit constellation A guiding low-Earth orbit constellation B using a sliding window and Bayesian conditional probability, such as... Figure 4 As shown, it specifically includes:

[0102] Step S601: Input the observation window set of constellation B for region O. ;

[0103] Step S602: Set the dwell time of the window-type target to a constant. Set the time for the target dwell window to slide to the right on the timeline in each iteration to . Set the preparation time for inter-constellation collaborative guidance to a constant. This represents the total time from when satellite A of constellation begins observing region O to when satellite B receives guidance information and completes mission preparation;

[0104] Step S603: Initialize the current time as The target's dwell time window at the current moment for Initialize the total number of target resident windows. ;

[0105] Step S604: Determine the target's dwell time window at the current moment. Has the end time been exceeded? , is represented as: ;

[0106] If the inequality is true, proceed to step S608; if it is true, proceed to step S605.

[0107] Step S605, Total number of target resident windows ;

[0108] Step S606: Calculate the current target dwell time window. The conditions for successful coordinated observation of constellations A and B are as follows; a schematic diagram of the observation windows for constellations A and B that meet the conditions for successful coordinated observation is shown below. Figure 5 As shown.

[0109] Depend on Figure 5 It can be seen that the time interval from the start of observation by constellation A satellite to the start of observation by the guided constellation B satellite is defined as... Constellation A satellites begin observations immediately upon the target's initial stationary position, at intervals... Maximum; to ensure successful guidance of Constellation B satellite observations, this interval must not be less than the inter-constellation coordinated guidance preparation time. Therefore, in For constellations A and B to complete coordinated observation of the target at a given moment, the following two conditions must be met simultaneously:

[0110] ① The observation window of constellation B includes the target's dwell time window at the current moment. Inside;

[0111] ② The time interval from when observations begin on satellite A of constellation A to when observations begin on satellite B of constellation B, which is being guided. It should be greater than or equal to the guidance preparation time. .

[0112] Assume that satellites in high-orbit constellation A can observe at any time, and the probability of observation at each time time follows a uniform distribution. Define the event. This indicates the current target dwell time window is... ;event Successful coordinated observation of window-shaped targets within region O by constellations A and B; event The high-orbit constellation A successfully observed a window-shaped target within region O; event The observation window for constellation B is included in the target dwell time window at the current moment. Inside. when event At the time of its establishment, the satellites of the High Orbit Constellation A could conduct observations at any time within the target's dwell window. Therefore, in the event and events Below, the event The conditional probability of occurrence can be expressed as:

[0113]

[0114] in, In the formula The i-th observation window corresponding to constellation B satellites The left endpoint time, this observation window is within the target dwell time window at time k; To guide preparation time ; The duration for which a window-type target remains in the window.

[0115] Step S607, Time Slide the target dwell time window to the right. Target dwell time window Represented as ;

[0116] Repeat steps S604 to S607 until the target dwell time window exceeds the end time. Then proceed to step S608;

[0117] Step S608: Based on the conditional probability at each time point Among them, the event For the successful coordinated observation of window-shaped targets within region O by constellations A and B, the event... The event indicates that the high-orbit constellation A successfully observed a window-shaped target within region O. This indicates the current target dwell time window is... According to Bayes' theorem, after constellation A successfully searches for and observes the target, the probability that constellation B will successfully observe the window-shaped target within region O is expressed as:

[0118]

[0119] in, The total number of target dwell windows is obtained by cyclically accumulating in step S605; since the target dwell windows slide uniformly over time, the events... The probability follows a uniform distribution. ;

[0120] Step S7: Output the collaborative observation probability results.

[0121] If the area to be observed, O, is not within the observable range of constellation A, constellation B cannot be guided to conduct cooperative observation, the probability of cooperative observation is 0, and the process ends.

[0122] In summary, the multi-satellite constellation probability estimation method for window-type targets based on sliding windows of the present invention simulates the random appearance of targets over a period of time by means of sliding target windows, and gives the target collaborative observation probability by considering factors such as satellite revisit and preparation time for collaborative guidance between different constellations. In the present invention, for the case of medium and low orbit satellites guiding low orbit satellites, the collaborative observation probability of window-type targets is proposed, as well as the conditional probability of the guided satellite successfully verifying the target under the condition that the preceding satellite successfully searches for the target; for the case of high orbit satellites guiding low orbit satellites, the conditional probability of the guided satellite successfully verifying the target under the condition that the high orbit satellite successfully searches for the target is proposed.

[0123] It should also be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or terminal device. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or terminal device that includes said element.

[0124] Finally, it should be noted that the above description represents a preferred embodiment of the present invention. It should be pointed out that although preferred embodiments have been described, those skilled in the art, once they understand the basic inventive concept of the present invention, can make various improvements and modifications without departing from the principles described herein. These improvements and modifications should also be considered within the scope of protection of the present invention. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the embodiments of the present invention.

Claims

1. A multi-satellite collaborative observation probability estimation method for window-shaped targets, characterized in that, Includes the following steps: Step S1: Input the statistical time range, the orbital elements and payload observation range of the guiding constellation A, and the orbital elements and payload observation range of the guided constellation B; Step S2: Determine the observation area O and determine whether constellation A is a geostationary orbit satellite. If yes, proceed with steps S3 and S4 in sequence. If no, proceed with steps S5 and S6 in sequence. Step S3: If constellation A is a non-geostationary orbit satellite, then calculate the set of observation windows for constellations A and B for region O; Step S4: Based on the observation window set, simulate the target appearance time using a sliding window, and calculate the probability of coordinated observation of the window-type target by constellation A guiding constellation B. Step S5: If constellation A is a geostationary orbit satellite, then calculate the set of observation windows of constellation B for region O; Step S6: Based on the observation window set, calculate the cooperative observation probability of constellation A guiding low-Earth orbit constellation B through a sliding window and Bayesian conditional probability. Step S7: Output the collaborative observation probability results.

2. The multi-satellite cooperative observation probability estimation method for window-type targets according to claim 1, characterized in that, Step S3 specifically includes: Based on the orbital elements of constellations A and B and the position of the region O to be observed, the set of observation windows for constellation A over the statistical time period is obtained. ,in, For the number of observation windows, This represents the time corresponding to the left endpoint of the i-th observation window interval. This represents the time corresponding to the right endpoint of the i-th observation window interval; Similarly, calculate the set of observation windows of constellation B over region O within the statistical time frame. ,in, For the number of observation windows, This represents the time corresponding to the left endpoint of the i-th observation window interval. This represents the time corresponding to the right endpoint of the i-th observation window interval.

3. The multi-satellite cooperative observation probability estimation method for window-type targets according to claim 1, characterized in that, Step S4 specifically includes: Step S401: Input the observation window set of constellation A and constellation B for region O. and ; Step S402: Set the dwell time of a window-type target to a constant. Set the time for the target dwell window to slide to the right on the timeline in each iteration to . Set the constellation-based collaborative guidance preparation time to a constant. This represents the total time from when satellite A of constellation begins observing region O to when satellite B of constellation receives guidance information and completes mission preparation; Step S403: Initialize the current time as The target's dwell time window at the current moment for Initialize the total number of target resident windows. The number of times constellation A successfully observed the target was: The number of times that constellation A and constellation B successfully completed coordinated observations of the target is: ; Step S404: Determine the target's dwell time window at the current moment. Has the end time been exceeded? , is represented as: ; If the inequality is true, proceed to step S411; if it is true, proceed to step S405. Step S405, Total number of target resident windows ; Step S406: Traverse the observation window set of constellation A Determine the target's dwell time window at the current moment. Does it contain an observation window? That is, satisfying and ; If the conditions are met, the observation window of constellation A can successfully observe the target, and then proceed to step S407; if the conditions are not met, the observation is considered to have failed, and then proceed to step S410. Step S407: The number of times constellation A successfully observed the target is... ; Step S408: Determine the target's dwell time window at the current moment. Does the data contain observation windows for constellation A and constellation B that meet the requirements for successful collaborative observation? If yes, proceed to step S409; otherwise, proceed to step S410. Step S409, the number of times constellation A and constellation B successfully completed collaborative observation of the target. ; Step S410, Time Slide the target dwell time window to the right. Target dwell time window Represented as ; Repeat steps S404 to S410 until the target dwell time window exceeds the end time. Then proceed to step S411; Step S411: Successful coordinated observation of a window-shaped target within region O by constellations A and B is recorded as an event. Its probability is expressed as: ; Step S412: According to Bayes' theorem, after constellation A successfully searches and observes the target, the probability of guiding constellation B to successfully observe it is expressed as: Among them, the event The successful coordinated observation of a window-shaped target within region O by constellations A and B is recorded as an event; Constellation A successfully searched for and observed window-shaped targets within region O.

4. The multi-satellite cooperative observation probability estimation method for window-type targets according to claim 1, characterized in that, Step S6 specifically includes, Step S601: Input the observation window set of constellation B for region O. ; Step S602: Set the dwell time of the window-type target to a constant. ; Set the time for the target dwell window to slide to the right on the timeline in each iteration to be... ; Set the inter-constellation collaborative guidance preparation time to a constant. This represents the total time from when satellite A of constellation begins observing region O to when satellite B receives guidance information and completes mission preparation; Step S603: Initialize the current time as The target's dwell time window at the current moment for Initialize the total number of target resident windows. ; Step S604: Determine the target's dwell time window at the current moment. Has the end time been exceeded? , is represented as: ; If the inequality is true, proceed to step S608; if it is true, proceed to step S605. Step S605, Total number of target resident windows ; Step S606: Calculate the current target dwell time window. The conditional probability that constellation A successfully observes the target and then guides constellation B to successfully observe the target. Step S607, Time Slide the target dwell time window to the right. Target dwell time window Represented as ; Repeat steps S604 to S607 until the target dwell time window exceeds the end time. Then proceed to step S608; Step S608: Based on the conditional probability at each time point Among them, the event For the successful coordinated observation of window-shaped targets within region O by constellations A and B, the event... For constellation A to successfully observe a window-shaped target within region O, event This indicates the current target dwell time window is... According to Bayes' theorem, after constellation A successfully searches for and observes the target, the probability that constellation B will successfully observe the window-shaped target within region O is expressed as: in, The total number of target dwell windows is obtained by cyclically accumulating in step S605; since the target dwell windows slide uniformly over time, the events... The probability follows a uniform distribution. .

5. The multi-satellite cooperative observation probability estimation method for window-type targets according to claim 4, characterized in that, In step S6, events are defined. This indicates the current target dwell time window is... ;event Successful coordinated observation of window-shaped targets within region O by constellations A and B; event The observation window for constellation B is included in the target dwell time window at the current moment. Inside; then in the event and events Below, the event The conditional probability of occurrence is expressed as: in, In the formula The i-th observation window corresponding to constellation B satellites The left endpoint time, this observation window is within the target dwell time window at time k; To guide preparation time ; The duration for which a window-type target remains in the window.

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