Attenuation Rate Calculation Method and System, Adjustment Method and System, Device and Medium

Abstract

The present invention relates to the technical field of satellite orbit calculation, and provides a decay rate calculation method and system, an adjustment method and system, a device, and a medium; the method includes the following steps: S1: Obtain the current orbit altitude of a sun-synchronous satellite; S2: Determine a data acquisition period according to the current orbit altitude; S3: Start collecting orbit altitude data within the data acquisition period from the current moment; S4: Fit the collected orbit altitude data into a linearly decreasing straight line and obtain a straight line formula; S5: Calculate the decay rate of the sun-synchronous satellite according to the straight line formula. This solution can accurately calculate the decay rate of a sun-synchronous satellite and timely adjust the satellite orbit altitude, enabling the satellite to perform its tasks more effectively.

Description

Technical Field

[0001] The present invention relates to the technical field of satellite orbit calculation, and particularly to a decay rate calculation method and system, an adjustment method and system, a device, and a medium. Background Art

[0002] A sun-synchronous orbit satellite is a satellite operating in a sun-synchronous orbit. The satellite orbit plane passes through the Earth's north and south poles and moves eastward by 0.9856 degrees every day, which is exactly the angle that the Earth moves eastward around the sun every day. The sun-synchronous satellite has the following characteristics:

[0003] First, timed observation: The sun-synchronous satellite enables the satellite to pass over a specific ground point at fixed time intervals. This is very important for tasks that require timed observations, such as Earth observation, meteorological monitoring, ocean monitoring, etc. The sun-synchronous satellite passes over the Earth almost at the same time each time, making the observation data more comparable and facilitating long-term trend analysis and time series observations.

[0004] Second, global coverage: The sun-synchronous orbit can achieve continuous observation coverage of the entire Earth. Due to the characteristics of the orbit, the orbital inclination of the sun-synchronous satellite is usually close to 90 degrees, enabling the satellite to cover approximately the same longitude range each time it enters a hemisphere of the Earth, achieving balanced observations of different regions of the Earth.

[0005] Third, sunlight conditions: The sun-synchronous orbit ensures that the satellite has similar sunlight conditions over the Earth. The orbital inclination and altitude of the sun-synchronous satellite are precisely designed so that the satellite can receive similar sunlight at different seasons and different locations, maintaining consistent lighting conditions and making the observation data more stable and reliable.

[0006] Fourth, communication and data downlink: The sun-synchronous orbit is relatively fixed in time and position over the Earth, facilitating communication and data downlink between the satellite and the ground station. This enables the satellite to transmit observation data, control commands, and status information in a timely manner, ensuring the normal collection and processing of data.

[0007] Therefore, many low-orbit satellites choose the sun-synchronous orbit, which can provide stable observation conditions and data continuity, enabling the satellite to perform its tasks more effectively.

[0008] During the orbital operation of a satellite, it is affected by various perturbing forces, which may cause orbital deviations and changes. Common perturbing forces include the Earth's non-spherical perturbing force, the gravitational forces of the sun and the moon, atmospheric drag, solar radiation pressure, tidal forces, etc. Sun-synchronous satellites are mainly affected by the Earth's non-spherical perturbing force and atmospheric drag, which cause the orbital altitude to continuously decrease. Especially during the high solar activity years, the satellite decays faster. The stability of the orbit is crucial for satellite communication, observation, navigation and other tasks. If the satellite decay rate exceeds the expected range, orbital control methods need to be used to keep the satellite running on the correct orbit. Therefore, it is very important to know the decay rate of sun-synchronous satellites. By analyzing the decay rate, the resources that the satellite may need in the future, such as fuel, power, and transmission bandwidth, can be predicted, which helps to optimize resource allocation and ensure the sustainable development of the satellite system.

[0009] Existing technologies usually directly subtract the instantaneous root or mean root semi-major axis at the start and end times of a certain period of the satellite, and then divide by the elapsed time to obtain the daily decay of the satellite. The disadvantages of this calculation method are as follows:

[0010] First, the difference between the mean root and the instantaneous root lies in considering the influence of perturbing forces on the orbit. Since the mean root eliminates short-period variations and only considers long-term variation terms, reflecting the long-term variation trend of the orbit, it greatly simplifies the orbital perturbation analysis. Therefore, the mean root should be used to calculate the orbital altitude of the satellite.

[0011] Second, due to the fluctuation of the orbit, the decay rate obtained by directly subtracting the semi-major axis at the start and end times of a certain period of the satellite has low accuracy, ignoring the intermediate fluctuation situation and unable to comprehensively reflect the data changes.

[0012] Therefore, it is necessary to provide a decay rate calculation method and system, an adjustment method and system, a device and a medium to accurately calculate the decay rate of sun-synchronous satellites, timely adjust the satellite orbital altitude, so that the satellite can perform its tasks more effectively.

[0013] The above information disclosed in the background art section is only used to enhance the understanding of the background of the present application. Therefore, it may include information that does not constitute the prior art known to those of ordinary skill in the art. Summary of the Invention

[0014] The main objective of the present invention is to overcome the problem of inaccurate calculation of the decay rate of sun-synchronous satellites, and provide a decay rate calculation method and system, an adjustment method and system, a device and a medium to accurately calculate the decay rate of sun-synchronous satellites, timely adjust the satellite orbital altitude, so that the satellite can perform its tasks more effectively.

[0015] To achieve the above objective, the first aspect of the present invention provides a decay rate calculation method applicable to sun-synchronous satellites, including the following steps:

[0016] S1: Obtain the current orbital altitude of the sun-synchronous satellite;

[0017] S2: Determine the data acquisition period according to the current orbital altitude;

[0018] S3: Start collecting orbital altitude data within the data acquisition period from the current moment;

[0019] S4: Fit the collected orbital altitude data into a linearly decreasing straight line and obtain the straight line formula;

[0020] S5: Calculate the decay rate of the sun-synchronous satellite according to the straight line formula.

[0021] According to a specific embodiment of the present invention, the sun-synchronous satellite is a satellite operating in a sun-synchronous orbit. The sun-synchronous satellite rotates around the earth, and the satellite orbit plane passes through the north and south poles of the earth and moves eastward by 0.9856 degrees every day. This angle is exactly the angle that the earth moves eastward around the sun every day.

[0022] According to a specific embodiment of the present invention, in step S1, it further includes: if the current orbital altitude is higher than or equal to 300 km and not higher than 6000 km, then proceed to step S2, otherwise abandon the decay rate calculation.

[0023] The inclination angle of the sun-synchronous orbit must be greater than 90°, that is, it is a retrograde orbit. In a circular orbit, the maximum inclination angle is 180°, so the altitude of the sun-synchronous orbit will not exceed 6000 km. The lower the orbital altitude, the greater the atmospheric drag and the faster the semi-major axis decays. For satellites with an orbital altitude below 300 km, the calculated decay amount fluctuates greatly every day, so no analysis is done. Under the condition of stable space environment and no satellite maneuvers, data for about half a month can be selected for analysis. If there are relatively active solar activities such as geomagnetic storms during this period, this data needs to be excluded before analysis.

[0024] According to a specific embodiment of the present invention, in step S3, the collecting of the orbital altitude data within the data acquisition period from the current moment includes: collecting the orbital altitude data within the data acquisition duration from the current moment at every specified time; the specified time is not less than 1 minute and not higher than 1 hour.

[0025] According to a specific embodiment of the present invention, in step S4, the fitting of the collected orbital altitude data into a linearly decreasing straight line includes: using a linear regression fitting method.

[0026] Sun-synchronous orbit satellites are mainly affected by the non-spherical perturbation force of the Earth and atmospheric drag, causing the orbit altitude to basically show a linear decay trend over a period of time. Therefore, a linear regression fitting method is adopted. The basic idea is to find a straight line that can best describe the relationship between data points. Specifically, the goal of linear regression is to find a straight line such that the sum of the perpendicular distances from all data points to this line is minimized.

[0027] According to a specific embodiment of the present invention, in step S5, the calculating the decay rate of the sun-synchronous satellite according to the straight-line formula includes:

[0028] The straight-line formula includes a slope, and the decay rate of the sun-synchronous satellite is obtained according to the slope;

[0029] The obtaining the decay rate of the sun-synchronous satellite according to the slope includes: obtaining the amount of decay of the semi-major axis of the satellite orbit per minute according to the slope, and calculating the amount of decay of the semi-major axis of the satellite orbit per day according to the amount of decay of the semi-major axis of the satellite orbit per minute, that is, the decay rate of the sun-synchronous satellite.

[0030] As a second aspect of the present invention, there is provided a decay rate calculation system applicable to sun-synchronous satellites, including:

[0031] A current orbit altitude module, configured to obtain the current orbit altitude of the sun-synchronous satellite;

[0032] A time period determination module, communicatively connected to the current orbit altitude acquisition module, and configured to determine a data acquisition time period according to the current orbit altitude;

[0033] An acquisition module, communicatively connected to the time period determination module and the current orbit altitude acquisition module, and configured to acquire orbit altitude data within the data acquisition time period starting from the current moment;

[0034] A fitting module, communicatively connected to the acquisition module, and configured to fit the acquired orbit altitude data into a linearly decreasing straight line and obtain a straight-line formula;

[0035] A decay rate calculation module, communicatively connected to the fitting module, and configured to calculate the decay rate of the sun-synchronous satellite according to the straight-line formula.

[0036] As a third aspect of the present invention, the present invention provides a method for adjusting the altitude of a sun-synchronous satellite, including the following steps:

[0037] Calculating the decay rate of the sun-synchronous satellite according to the decay rate calculation method applicable to the sun-synchronous satellite;

[0038] Determining the semi-major axis increment and time interval required to adjust the satellite trajectory according to the decay rate; adjusting the orbit of the satellite according to the semi-major axis increment and time interval required to adjust the satellite trajectory.

[0039] As an exemplary embodiment of the present invention, the satellite trajectory is adjusted to the east of the nominal trajectory and the semi-major axis increment required for adjustment is 2△a, and the adjustment time interval is ; where △λ represents the maximum value of the satellite sub-satellite point trajectory drift, that is, the geographical longitude range of the actual satellite sub-satellite point trajectory relative to the nominal trajectory is ± ; △a represents the semi-major axis increment required to control to the nominal trajectory when the satellite sub-satellite point trajectory drifts to the east boundary; represents the decay rate of the satellite orbit semi-major axis.

[0040] As the fourth aspect of the present invention, the present invention provides an altitude adjustment system suitable for a sun-synchronous satellite, which is characterized in that it includes: the decay rate calculation system suitable for a sun-synchronous satellite and an altitude adjustment module described above;

[0041] The altitude adjustment module is used to determine the semi-major axis increment and time interval required to adjust the satellite trajectory according to the decay rate of the sun-synchronous satellite calculated by the decay rate calculation system suitable for the sun-synchronous satellite; and adjust the satellite orbit according to the semi-major axis increment and time interval required to adjust the satellite trajectory.

[0042] As the fifth aspect of the present invention, the present invention provides an electronic device, including:

[0043] One or more processors;

[0044] A storage device for storing one or more programs;

[0045] When the one or more programs are executed by the one or more processors, the one or more processors implement the decay rate calculation method suitable for the sun-synchronous satellite.

[0046] As the sixth aspect of the present invention, the present invention provides a computer-readable medium, on which a computer program is stored, and when the program is executed by a processor, the decay rate calculation method suitable for the sun-synchronous satellite is implemented.

[0047] The advantageous effects of the present invention are:

[0048] The method of the present invention calculates the satellite orbit position within a predetermined time range by a fitting method, accurately calculates the decay rate of the sun-synchronous satellite, and timely adjusts the satellite orbit altitude, so that the satellite can perform its tasks more effectively. Description of the Drawings

[0049] These and other objectives, features, and advantages of the present application will become more apparent by describing its exemplary embodiments in detail with reference to the accompanying drawings. The following described drawings are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0050] Figure 1 A step diagram schematically showing a method for adjusting the altitude of a sun-synchronous satellite.

[0051] Figure 2 A graph schematically showing the changing trend of the semi-major axis of the orbit of a sun-synchronous satellite.

[0052] Figure 3 A comparison graph of the attenuation rate calculated in a specific embodiment and the true orbital altitude schematically shown.

[0053] Figure 4 A schematic diagram of the sub-satellite point trajectory control loop schematically shown.

[0054] Figure 5 A block diagram of an electronic device schematically shown.

[0055] Figure 6 A block diagram of a computer-readable medium schematically shown. Specific embodiments

[0056] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, the exemplary embodiments can be implemented in various forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this application will be thorough and complete, and will fully convey the concept of the exemplary embodiments to those skilled in the art. Like reference numerals in the figures denote like or similar parts, and thus their repeated description will be omitted.

[0057] In addition, the described features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided to give a thorough understanding of the embodiments of the present application. However, those skilled in the art will realize that the technical solutions of the present application can be practiced without one or more of the specific details, or other methods, components, devices, steps, etc. can be adopted. In other cases, well-known methods, devices, implementations, or operations are not shown or described in detail to avoid obscuring aspects of the present application.

[0058] The block diagrams shown in the drawings are merely functional entities and do not necessarily correspond to physically independent entities. That is, these functional entities can be implemented in software form, or implemented in one or more hardware modules or integrated circuits, or implemented in different networks and / or processor devices and / or microcontroller devices.

[0059] The flowcharts shown in the drawings are only illustrative descriptions and do not necessarily include all the contents and operations / steps, nor are they necessarily executed in the described order. For example, some operations / steps can be decomposed, while some operations / steps can be combined or partially combined. Therefore, the actual execution order may change according to the actual situation.

[0060] It should be understood that although terms such as first, second, and third may be used herein to describe various components, these components should not be limited by these terms. These terms are used to distinguish one component from another. Therefore, the first component discussed below can be referred to as the second component without departing from the teachings of the concept of the present application. As used herein, the term "and / or" includes any one of the associated listed items and all combinations of one or more of them.

[0061] Those skilled in the art can understand that the drawings are only schematic diagrams of exemplary embodiments, and the modules or processes in the drawings are not necessarily essential for implementing the present application. Therefore, they cannot be used to limit the protection scope of the present application.

[0062] According to the first specific embodiment of the present invention, the present invention provides a decay rate calculation system applicable to a sun-synchronous satellite, including:

[0063] A current orbit altitude module, configured to obtain the current orbit altitude of the sun-synchronous satellite;

[0064] A time period determination module, communicatively connected to the current orbit altitude acquisition module, and configured to determine a data acquisition time period according to the current orbit altitude;

[0065] An acquisition module, communicatively connected to the time period determination module and the current orbit altitude acquisition module, and configured to acquire orbit altitude data within the data acquisition time period starting from the current moment;

[0066] A fitting module, communicatively connected to the acquisition module, and configured to fit the acquired orbit altitude data into a linearly decreasing straight line and obtain a straight line formula;

[0067] A decay rate calculation module, communicatively connected to the fitting module, and configured to calculate the decay rate of the sun-synchronous satellite according to the straight line formula.

[0068] According to the second specific embodiment of the present invention, a decay rate calculation method applicable to sun-synchronous satellites is provided. Using the decay rate calculation system of the first specific embodiment, it includes the following steps:

[0069] S1: Obtain the current orbital altitude of the sun-synchronous satellite.

[0070] A sun-synchronous satellite is a satellite operating in a sun-synchronous orbit. This sun-synchronous satellite orbits the Earth, and the satellite orbit plane passes through the Earth's north and south poles and moves eastward by 0.9856 degrees every day. This angle is exactly the angle by which the Earth moves eastward in its revolution around the sun every day.

[0071] Step S1 further includes: If the current orbital altitude is higher than or equal to 300 km and not higher than 6000 km, then proceed to step S2; otherwise, abandon the decay rate calculation.

[0072] The inclination of the sun-synchronous orbit must be greater than 90°, that is, it is a retrograde orbit. In a circular orbit, the maximum inclination is 180°, so the altitude of the sun-synchronous orbit will not exceed 6000 km. The lower the orbital altitude, the greater the atmospheric drag and the faster the semi-major axis decays. For satellites with an orbital altitude below 300 km, the calculated decay amount fluctuates greatly every day, so no analysis is done. Under the condition of a stable space environment and no maneuvers of the satellite, data for about half a month can be selected for analysis. If there are relatively active solar activities such as geomagnetic storms during this period, this data point needs to be excluded before analysis.

[0073] S2: Determine the data acquisition period according to the current orbital altitude.

[0074] S3: Start collecting orbital altitude data within the data acquisition period from the current moment.

[0075] The step of starting to collect orbital altitude data within the data acquisition period from the current moment includes: Collecting orbital altitude data within the data acquisition duration from the current moment at specified intervals; the specified time is not less than 1 minute and not higher than 1 hour. The specified time mainly depends on the data acquisition duration, and the more data points, the better.

[0076] S4: Fit the collected orbital altitude data into a linearly decreasing straight line and obtain the straight line formula.

[0077] The step of fitting the collected orbital altitude data into a linearly decreasing straight line includes: Using the fitting method of linear regression.

[0078] During the orbital operation of a satellite, it is affected by various perturbing forces, which may cause the orbit to deviate and change. Common perturbing forces include the non-spherical Earth perturbing force, the gravitational forces of the sun and moon, atmospheric drag, solar radiation pressure, tidal forces, etc. The representation types of satellite orbits are instantaneous elements and mean elements. Instantaneous elements refer to the orbital elements of a satellite at a certain moment, which describe the position and velocity of the satellite at that moment. Mean elements refer to the average elements obtained by averaging the satellite orbit, which describe the average properties of the satellite orbit. The difference between mean elements and instantaneous elements lies in considering the influence of perturbing forces on the orbit. Since mean elements eliminate short-period variations and only consider long-term variation terms, reflecting the long-term variation trend of the orbit, greatly simplifying the analysis of orbital perturbing forces, mean elements are often used to analyze the orbital situation of satellites.

[0079] Figure 2 The variation trends of the semi-major axis of the sun-synchronous satellite orbits with three different orbital altitudes and different local times of the descending node are analyzed. Among them, Line 1 represents a sun-synchronous orbit satellite with a semi-major axis of 600 km, Line 2 represents a sun-synchronous orbit satellite with a semi-major axis of 550 km, and Line 3 represents a sun-synchronous orbit satellite with a semi-major axis of 500 km. It can be observed that the sun-synchronous satellites are mainly affected by the non-spherical Earth perturbing force and atmospheric drag, resulting in a linear decay trend of the orbital altitude.

[0080] Sun-synchronous orbit satellites are mainly affected by the non-spherical Earth perturbing force and atmospheric drag, resulting in a basically linear decay trend of the orbital altitude within a certain period of time. Therefore, the fitting method of linear regression is adopted. Its basic idea is to find a straight line that can best describe the relationship between data points. Specifically, the goal of linear regression is to find a straight line such that the sum of the perpendicular distances from all data points to this straight line is minimized.

[0081] The semi-major axis of the orbit over a period of time is fitted into a linearly decreasing straight line and the straight line formula is represented. Using the fitting results to obtain information such as the slope and intercept to further analyze the characteristics and laws of the data, and calculate the daily decay situation of the satellite. Such a method can better reflect the overall trend and changes of the data. Multiple data points are used for calculation, which is more comprehensive than the method of only considering the difference between the first and last two points.

[0082] S5: Calculate the decay rate of the sun-synchronous satellite according to the straight line formula.

[0083] In step S5, the calculating the decay rate of the sun-synchronous satellite according to the straight line formula includes:

[0084] The straight line formula includes the slope, and the decay rate of the sun-synchronous satellite is obtained according to the slope;

[0085] The obtaining of the decay rate of a sun-synchronous satellite based on the slope includes: obtaining the amount of decay of the semi-major axis of the satellite orbit per minute according to the slope, and calculating the amount of decay of the semi-major axis of the satellite orbit per day based on the amount of decay of the semi-major axis of the satellite orbit per minute, that is, the decay rate of the sun-synchronous satellite.

[0086] Fitting means connecting a series of points on a plane with a smooth curve. Since the orbital altitude of a sun-synchronous satellite approximately shows a linear decay, the semi-major axis of the sun-synchronous satellite's orbit is fitted into a linear straight line represented by a linear function of the form y = kx + b, where k is the decay rate. The amount of decay of the satellite orbit per day can be calculated based on the decay rate.

[0087] The inclination angle of a sun-synchronous satellite is about 90 degrees, which will cause the orbit to decay in a linear trend. For low-earth orbit satellites with medium and low inclination angles, due to the greater influence of the non-spherical perturbation force of the earth, the orbit fluctuates up and down and has a periodic trend of decay. The calculation method of the decay rate of other low-earth orbit satellites (low-earth orbit satellites with medium and low inclination angles) cannot be directly applied to the calculation method of the decay rate of sun-synchronous satellites. For low-earth orbit satellites, the lower the orbital altitude, the greater the atmospheric drag, the faster the satellite decays, and the greater the slope.

[0088] The slope obtained by fitting is the decay rate of the semi-major axis of the satellite orbit.

[0089] Suppose the linear expression obtained by fitting 1000 pieces of satellite orbit semi-major axis data at 1-minute intervals is y = -0.088x + 6378110 (unit of the y-axis: meter, unit of the x-axis: minute). The meaning of this linear expression is that the semi-major axis of this satellite orbit decays by 0.088 meters per minute, that is, the decay rate of the semi-major axis of the satellite orbit is 0.088 (m / min) * 24 (h / day) * 60 (min / h) = 126.72 (m / day).

[0090] As Figure 3 shown, the orbital change of a sun-synchronous satellite with an orbital altitude of 500 km in 100 days is shown by the scatter curve of Line 1 in the following figure. By fitting the scatter points, the Figure 3 dashed line of Line 2 is obtained, which is the overall decay situation of the satellite. According to the trend formula of orbital decay y = -0.0127x + 6870.2 (unit of the x-axis: hr, unit of the y-axis: km), it is calculated that the average daily decay is 0.3048 km. If the previous method for calculating the orbital decay rate is used, the average daily decay is 0.2938 km, and the error from the result of the present invention is 0.011 km. In addition, by comparing the actual orbit with the fitted orbit, the change situation of the space environment and the influence of external factors on the satellite orbit can be analyzed.

[0091] The method of the present invention calculates the satellite orbital position within a predetermined time range through a fitting method, accurately calculates the decay rate of a sun-synchronous satellite, and timely adjusts the satellite orbital altitude, enabling the satellite to perform its tasks more effectively.

[0092] After obtaining the decay rate of the sun-synchronous satellite, the orbital altitude of the sun-synchronous satellite can be adaptively adjusted according to the decay rate.

[0093] According to the third specific embodiment of the present invention, the present invention provides a height adjustment system applicable to a sun-synchronous satellite, which is characterized by including: a decay rate calculation system applicable to a sun-synchronous satellite and a height adjustment module of the first specific embodiment;

[0094] The height adjustment module is used to determine the semi-major axis increment and time interval required for adjusting the satellite trajectory according to the decay rate of the sun-synchronous satellite calculated by the decay rate calculation system applicable to the sun-synchronous satellite; and adjust the orbit of the satellite according to the semi-major axis increment and time interval required for adjusting the satellite trajectory.

[0095] According to the fourth specific embodiment of the present invention, the present invention provides a height adjustment method applicable to a sun-synchronous satellite, adopting the height adjustment system applicable to a sun-synchronous satellite of the third specific embodiment, including the following steps:

[0096] Calculate the decay rate of the sun-synchronous satellite according to the decay rate calculation method applicable to the sun-synchronous satellite of the second specific embodiment;

[0097] Step S6: Determine the semi-major axis increment and time interval required for adjusting the satellite trajectory according to the decay rate; and adjust the orbit of the satellite according to the semi-major axis increment and time interval required for adjusting the satellite trajectory.

[0098] Adjust the satellite trajectory to the east of the nominal trajectory is carried out, the required semi-major axis increment for adjustment is 2△a, and the adjustment time interval is ; where, △λ represents the maximum value of the satellite sub-satellite point trajectory drift, that is, the geographical longitude range of the actual satellite sub-satellite point trajectory relative to the nominal trajectory is ; △a represents the semi-major axis increment required to control to the nominal trajectory when the satellite sub-satellite point trajectory drifts to the east boundary; represents the decay rate of the satellite orbit semi-major axis.

[0099] During the long-term orbital operation of the satellite, due to the influence of atmospheric drag, the non-spherical gravity of the Earth, and the gravitational perturbations of the sun and moon, the semi-major axis will continuously decay, resulting in the ground track drifting eastward and deviating from the nominal orbit. Therefore, to maintain the regression characteristics of the satellite orbit, it is necessary to periodically adjust the semi-major axis to maintain the performance indicators of the actual operating orbit. That is to say, it meets the requirements when the satellite's sub-satellite point track remains within a certain range near the nominal track, and orbit maintenance must be carried out if it exceeds the range.

[0100] The influence of atmospheric drag on the orbit is mainly to cause the decay of the semi-major axis a, and its decay rate is:

[0101] ;

[0102] Among them, is the decay rate, C D is the drag coefficient, A is the satellite's windward area, m is the satellite's mass, n is the satellite's mean motion angular velocity, is the atmospheric density at the corresponding altitude.

[0103] Assume that the actual track remains within the range of east and west of the nominal track, then the change range of the semi-major axis should be:

[0104] ;

[0105] Among them is the satellite's nominal mean semi-major axis, that is, each control is carried out on the east side of the nominal track , the adjustment amount of the semi-major axis is 2△a, and the adjustment time interval is (as Figure 4 shown).

[0106] Figure 4 The abscissa represents the geographical longitude of the sub-satellite point, and the ordinate is the satellite's mean semi-major axis, is the satellite's nominal mean semi-major axis, △a represents the increment of the semi-major axis required to control to the nominal track when the satellite's sub-satellite point track drifts to the east boundary; λ 0 is the nominal sub-satellite point longitude, △λ represents the maximum drift of the satellite's sub-satellite point track, that is, the geographical longitude range of the satellite's actual sub-satellite point track relative to the nominal track is .

[0107] During the on-orbit flight of the satellite, it will be affected by various perturbing forces, resulting in a gradual decrease in the satellite's mean semi-major axis. When the satellite's mean semi-major axis is greater than the nominal mean semi-major axis, the sub-satellite point track drifts westward; when the satellite's mean semi-major axis is greater than the nominal mean semi-major axis, the sub-satellite point track drifts eastward. Therefore, by adjusting the mean semi-major axis, the satellite's sub-satellite point track can be maintained within during the period.

[0108] Figure 4 It shows that when the sub-satellite point longitude is and the mean semi-major axis is , after the mean semi-major axis is lifted by 2△a and the satellite mean semi-major axis is greater than the nominal mean semi-major axis, the sub-satellite point track drifts westward; when it drifts westward to , the mean semi-major axis is ; when the mean semi-major axis is less than the nominal mean semi-major axis, the sub-satellite point track drifts eastward; when it drifts eastward to , the mean semi-major axis is ; repeat the above operations to maintain the sub-satellite point track.

[0109] In summary, according to the decay rate of the satellite, the increment of the semi-major axis, the holding period, the control frequency, etc. required for satellite track maintenance can be calculated.

[0110] According to the fifth specific embodiment of the present invention, the present invention provides an electronic device, as Figure 5 shown, Figure 5 is a block diagram of an electronic device shown according to an exemplary embodiment.

[0111] Next, refer to Figure 5 to describe the electronic device 500 according to this embodiment of the present application. Figure 5 The electronic device 500 shown is only an example and should not impose any limitation on the functions and usage scope of the embodiments of the present application.

[0112] As Figure 5 shown, the electronic device 500 is presented in the form of a general computing device. The components of the electronic device 500 may include but are not limited to: at least one processing unit 510, at least one storage unit 520, a bus 530 connecting different system components (including the storage unit 520 and the processing unit 510), a display unit 540, etc.

[0113] Among them, the storage unit stores program codes, and the program codes can be executed by the processing unit 510, so that the processing unit 510 executes the steps according to various exemplary embodiments of the present application described in this specification. For example, the processing unit 510 can execute the steps shown in the second specific embodiment.

[0114] The storage unit 520 may include a readable medium in the form of a volatile storage unit, such as a random access storage unit (RAM) 5201 and / or a cache storage unit 5202, and may further include a read-only storage unit (ROM) 5203.

[0115] The storage unit 520 may also include a program / utility 5204 having a set (at least one) of program modules 5205. Such program modules 5205 include, but are not limited to, an operating system, one or more application programs, other program modules, and program data. Each or some combination of these examples may include an implementation of a network environment.

[0116] The bus 530 may represent one or more of several types of bus structures, including a memory bus or memory controller, a peripheral bus, an accelerated graphics port, a processing unit, or a local bus using any of a variety of bus structures.

[0117] The electronic device 500 may also communicate with one or more external devices 500' (such as a keyboard, a pointing device, a Bluetooth device, etc.), enabling the user to interact with the electronic device 500, and / or communicate with any device that enables the electronic device 500 to communicate with one or more other computing devices (such as a router, a modem, etc.). Such communication may be through the input / output (I / O) interface 550. Moreover, the electronic device 500 may also communicate with one or more networks (such as a local area network (LAN), a wide area network (WAN), and / or a public network, such as the Internet) through the network adapter 460. The network adapter 560 may communicate with other modules of the electronic device 500 through the bus 530. It should be understood that, although not shown in the figure, other hardware and / or software modules may be used in conjunction with the electronic device 500, including but not limited to: microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, tape drives, and data backup storage systems, etc.

[0118] Through the description of the above embodiments, those skilled in the art can easily understand that the example embodiments described herein can be implemented by software or by a combination of software and necessary hardware.

[0119] Therefore, according to the sixth specific embodiment of the present invention, the present invention provides a computer-readable medium. As Figure 6 shown, the technical solution according to the embodiment of the present invention can be embodied in the form of a software product, which can be stored in a non-volatile storage medium (which may be a CD-ROM, a USB flash drive, a mobile hard disk, etc.) or on a network, including several instructions to enable a computing device (which may be a personal computer, a server, or a network device, etc.) to execute the above method according to the embodiment of the present invention.

[0120] The software product may employ any combination of one or more readable media. The readable media may be a readable signal medium or a readable storage medium. The readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination of the foregoing. More specific examples (a non-exhaustive list) of the readable storage medium include: an electrical connection having one or more wires, a portable disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0121] The computer-readable storage medium may include a data signal propagated in a baseband or as part of a carrier wave, in which the readable program code is carried. Such a propagated data signal may take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the foregoing. The readable storage medium may also be any readable medium other than the readable storage medium, which can send, propagate, or transmit a program for use by or in connection with an instruction execution system, apparatus, or device. The program code contained on the readable storage medium may be transmitted using any appropriate medium, including but not limited to wireless, wireline, optical fiber cable, RF, etc., or any suitable combination of the foregoing.

[0122] The program code for performing the operations of the present invention may be written in any combination of one or more programming languages, including object-oriented programming languages such as Java, C++, etc., and also including conventional procedural programming languages such as the "C" language or similar programming languages. The program code may be executed entirely on the user's computing device, partially on the user's device, executed as a stand-alone software package, partially on the user's computing device and partially on a remote computing device, or entirely on the remote computing device or server. In the case of a remote computing device, the remote computing device may be connected to the user's computing device through any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computing device (e.g., through the Internet using an Internet service provider).

[0123] The above computer-readable medium carries one or more programs, which, when executed by one of the devices, cause the computer-readable medium to implement the functions of the second specific embodiment.

[0124] Those skilled in the art can understand that the above-mentioned modules can be distributed in the device according to the description of the embodiments, or can be correspondingly changed and distributed in one or more devices that are only different from this embodiment. The modules of the above embodiments can be combined into one module, or further split into multiple sub-modules.

[0125] Through the description of the above embodiments, those skilled in the art can easily understand that the exemplary embodiments described herein can be implemented by software, or can be implemented by the way of software combined with necessary hardware. Therefore, the technical solution according to the embodiment of the present invention can be embodied in the form of a software product, and the software product can be stored in a non-volatile storage medium (which can be a CD-ROM, a USB flash drive, a mobile hard disk, etc.) or on a network, including several instructions to enable a computing device (which can be a personal computer, a server, a mobile terminal, or a network device, etc.) to execute the method according to the embodiment of the present invention.

[0126] The above specifically shows and describes the exemplary embodiments of the present invention. It should be understood that the present invention is not limited to the detailed structure, setting mode or implementation method described herein; on the contrary, the present invention is intended to cover various modifications and equivalent settings included in the spirit and scope of the appended claims.

Claims

1. A method for calculating the attenuation rate of a sun-synchronous satellite, characterized in that: The following steps are involved: S1: Get the current orbital altitude of the sun-synchronous satellite; A sun-synchronous satellite is a satellite operating in a sun-synchronous orbit. The sun-synchronous satellite revolves around the earth, and the satellite orbit plane passes through the north and south poles of the earth and moves eastward by 0.9856 degrees every day. The inclination angle of the sun-synchronous satellite is greater than 90 degrees. Step S1 also includes: if the current orbit altitude is higher than or equal to 300km and not higher than 6000km, then step S2 is performed, otherwise the attenuation rate calculation is abandoned; S2: Determine a data collection period according to the current orbit altitude; S3: starting from the current moment, collecting orbital height data within the data collection period; In step S3, the collecting of the orbit height data within the data collection duration from the current moment includes: collecting the orbit height data within the data collection duration from the current moment at specified intervals; the specified time is not less than 1 minute and not more than 1 hour; and selecting data for half a month; S4: Fitting the collected orbital height data into a linearly decreasing straight line and obtaining a straight line formula; S5: Calculate the attenuation rate of the sun-synchronous satellite according to the straight-line formula; In step S5, the attenuation rate of the sun-synchronous satellite is calculated according to the straight line formula, including: The straight line formula includes a slope, and the attenuation rate of the sun-synchronous satellite is obtained according to the slope; The method of obtaining the attenuation rate of a sun-synchronous satellite according to the slope includes: obtaining the attenuation of the semi-major axis of the satellite orbit per minute according to the slope, and calculating the attenuation of the semi-major axis of the satellite orbit per day according to the attenuation of the semi-major axis of the satellite orbit per minute, that is, the attenuation rate of the sun-synchronous satellite.

2. The attenuation rate calculation method applicable to a sun-synchronous satellite according to claim 1, characterized in that: In step S4, fitting the collected orbital height data into a linearly decreasing straight line includes: adopting a linear regression fitting method.

3. A decay rate calculation system suitable for a sun-synchronous satellite, characterized in that: include: The current orbit altitude acquisition module is used to acquire the current orbit altitude of the sun-synchronous satellite; A sun-synchronous satellite is a satellite operating in a sun-synchronous orbit. The sun-synchronous satellite revolves around the earth, and the satellite orbit plane passes through the north and south poles of the earth and moves eastward by 0.9856 degrees every day. The inclination angle of the sun-synchronous satellite is greater than 90 degrees. Step S1 also includes: if the current orbit altitude is higher than or equal to 300km and not higher than 6000km, then step S2 is performed, otherwise the attenuation rate calculation is abandoned; A time period determination module, communicatively connected to the current orbit height acquisition module, for determining a data collection time period according to the current orbit height; A collection module is communicatively connected with the time period determination module and the current orbit height acquisition module, and is used to collect orbit height data within the data collection period from the current moment; the collecting of orbit height data within the data collection duration from the current moment includes: collecting orbit height data within the data collection duration from the current moment at specified time intervals; the specified time is not less than 1 minute and not more than 1 hour; and selecting data for half a month; A fitting module, communicatively connected to the acquisition module, for fitting the acquired orbit height data into a linearly decreasing straight line and obtaining a straight line formula; The attenuation rate calculation module is communicatively connected to the fitting module and is used to calculate the attenuation rate of the sun-synchronous satellite according to the straight line formula; the attenuation rate of the sun-synchronous satellite calculated according to the straight line formula includes: The straight line formula includes a slope, and the attenuation rate of the sun-synchronous satellite is obtained according to the slope; The method of obtaining the attenuation rate of a sun-synchronous satellite according to the slope includes: obtaining the attenuation of the semi-major axis of the satellite orbit per minute according to the slope, and calculating the attenuation of the semi-major axis of the satellite orbit per day according to the attenuation of the semi-major axis of the satellite orbit per minute, that is, the attenuation rate of the sun-synchronous satellite.

4. A method for adjusting the altitude of a sun-synchronous satellite, characterized in that: The following steps are involved: Calculating the attenuation rate of a sun-synchronous satellite according to the attenuation rate calculation method applicable to a sun-synchronous satellite according to any one of claims 1 or 2; The semi-major axis increment and time interval required for adjusting the satellite trajectory are determined according to the attenuation rate; and the orbit of the satellite is adjusted according to the semi-major axis increment and time interval required for adjusting the satellite trajectory.

5. The altitude adjustment method for a sun-synchronous satellite according to claim 4, characterized in that: Adjust the satellite trajectory to the east of the nominal trajectory The semi-major axis increment required for adjustment is 2△a, and the adjustment time interval is ; Among them, △λ represents the maximum value of the satellite sub-satellite point trajectory drift, that is, the geographic longitude range of the satellite actual sub-satellite point trajectory relative to the nominal trajectory is ± ; △a represents the semi-major axis increment required to control the satellite sub-satellite point trajectory to the nominal trajectory when it drifts to the eastern boundary; Represents the decay rate of the semi-major axis of the satellite orbit.

6. An altitude adjustment system for a sun-synchronous satellite, characterized in that: include: The attenuation rate calculation system and altitude adjustment module applicable to a sun-synchronous satellite as described in claim 3; The altitude adjustment module is used to determine the semi-major axis increment and time interval required to adjust the satellite trajectory according to the attenuation rate of the sun-synchronous satellite calculated by the attenuation rate calculation system applicable to the sun-synchronous satellite; and adjust the orbit of the satellite according to the semi-major axis increment and time interval required to adjust the satellite trajectory.

7. An electronic device, characterized in that: include: one or more processors; A storage device for storing one or more programs; When the one or more programs are executed by the one or more processors, the one or more processors implement the attenuation rate calculation method applicable to a sun-synchronous satellite as described in any one of claims 1 or 2.

8. A computer readable medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the attenuation rate calculation method applicable to a sun-synchronous satellite as claimed in claim 1 or 2 is implemented.

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