Inter-satellite link fault avoidance method and system based on time quantitative calculation under sunshine effect

Abstract

The invention discloses an inter-satellite link fault avoidance method and system based on time quantitative calculation under the sun-sun effect, and mainly solves the problems that the calculation complexity of inter-satellite link faults of a satellite network is high and the link fault duration cannot be directly calculated under the influence of the sun-sun effect in the prior art. According to the implementation scheme, the method comprises the following steps: initializing constellation parameters, establishing a J2000.0 geocentric inertial coordinate system, and determining a satellite position at any moment; the right ascension and declination of the sun are calculated, the included angle between the sunlight and each satellite orbit plane is calculated according to the parameters, the link fault position existing in the orbit is determined, and the link fault range of each orbit is calculated; calculating positions and fault duration of all fault links in each orbit according to the link fault range and the positions of satellites; and the satellites autonomously perform link avoidance according to the link fault range and the fault duration. According to the method, the calculated amount can be effectively reduced, the response speed is improved, the duration of the link fault is directly obtained, and the method can be used for analyzing the inter-satellite link fault condition of the satellite network under the sun-sun effect.

Description

Technical Field

[0001] This invention belongs to the field of satellite network technology, and in particular relates to a method and system for inter-satellite link failure avoidance based on time-quantitative calculation. It can be used to calculate the failure time of inter-satellite links in satellite networks under the solar interference effect, so that satellites can effectively avoid the impact of solar interference on the links. Background Technology

[0002] Satellite networks are a crucial component of integrated space-ground information networks, and their reliable and stable operation is the cornerstone of ensuring the service capabilities of space information networks. With the increasing scale of satellite constellations, the periodic failures and outages of laser links between satellite nodes caused by solar interference severely impact satellite network performance. When satellites employ avoidance algorithms, they need to quickly and accurately predict the duration of link failures. Therefore, accurately analyzing satellite network link failures under the influence of solar interference and calculating their duration is a problem that urgently needs to be solved.

[0003] Patent application CN202510479634.8 discloses an optimal avoidance method for satellite laser communication under solar interference or interfering light sources. It acquires historical satellite position information through a remote telemetry receiver, establishes inter-satellite link vectors and the vector of sunlight relative to the satellites based on predicted position information, and then determines whether the angle between the inter-satellite link and the incident sunlight is less than a solar interference threshold. This method requires acquiring the position information of each satellite and calculating the angle between each inter-satellite link and the sun to obtain the status of all links in the entire satellite network, resulting in a large computational load. Furthermore, this method cannot directly calculate the duration of solar interference affecting the inter-satellite links.

[0004] Patent application CN202411563172.X discloses a method and system for avoiding solar interference in inter-satellite laser communication. When determining whether inter-satellite laser communication is affected by solar interference, it requires real-time calculation of the angle between the satellite's broadcast solar vector and the current optical axis pointing vector. Because this method requires real-time calculation of the angle between the satellite laser terminal's optical axis and the solar vector, the computational cost is significant when the constellation is large. Furthermore, the duration of the solar interference cannot be predicted; the link can only be re-established after a fixed period or after the calculated angle between the theoretical pointing vector and the solar vector exceeds a set threshold, making it highly unpredictable.

[0005] Patent application CN202311044174.3 discloses a method and system for avoiding solar interference on inter-satellite links. It first calculates the pointing vector of the inter-satellite link based on ephemeris information, satellite attitude, and solar vector. Finally, it calculates the angle between the pointing vector and the solar vector, using this angle to determine whether to initiate solar interference avoidance, thus enabling autonomous avoidance of solar interference based on satellite operational status. However, this method can only calculate the status of a single link and requires real-time acquisition of the position information of all satellites to obtain the status of all links. This approach not only places high demands on the satellite's computing performance but also cannot directly calculate the duration of solar interference affecting the inter-satellite link. Summary of the Invention

[0006] The purpose of this invention is to address the shortcomings of the prior art by proposing a time-based quantitative calculation method and system for inter-satellite link fault avoidance under the solar interference effect. This method enables the rapid and efficient determination of the region where a satellite network constellation experiences a link fault under the influence of solar interference, as well as the duration of the fault. This allows satellites to anticipate the start and end points of link avoidance, facilitating the initiation of avoidance operations before entering the fault region. This improves the operational efficiency and reliability of satellite links, reduces computational overhead, and increases response speed.

[0007] To achieve the above objectives, the technical solution of the present invention includes the following:

[0008] 1. A time-quantitative calculation-based inter-satellite link failure avoidance method under solar interference effect, characterized in that it includes:

[0009] S1) Initialize constellation parameters, establish the J2000.0 geocentric inertial coordinate system, and determine the satellite's position at any given time;

[0010] S2) Initialize the time t to be calculated and calculate the right ascension of the sun. declination ;

[0011] S3) Based on the constellation parameters and the right ascension and declination of the sun, calculate the angle between the sunlight and the orbital plane of each satellite, and compare it with the critical angle of link damage to determine whether there is a link fault location in the orbit.

[0012] S4) Calculate the link failure range of each orbit based on the angle between sunlight and the orbital plane of each satellite;

[0013] S5) Calculate the location and duration of all faulty links in each satellite orbit based on the link fault range and the satellite's location;

[0014] S6) The satellite autonomously avoids links based on the scope and duration of the link failure.

[0015] Furthermore, the initialization of constellation parameters, establishment of the J2000.0 geocentric inertial coordinate system, and determination of the satellite's position at any given time include:

[0016] Initialize the constellation's orbital altitude h, number of orbits P, number of satellites per orbit S, orbital inclination I, and phase factor F;

[0017] With the Earth's center as the origin, the X-axis points to the vernal equinox, the Z-axis points to the North Pole along the direction of the Earth's rotation axis, and the Y-axis is obtained according to the right-hand rule, thus establishing the J2000.0 geocentric inertial coordinate system;

[0018] According to the set satellite elevation angle Azimuth Right ascension of ascending node True near point angle These parameters determine the satellite's position at any given time.

[0019] Furthermore, the calculation of the link failure range is determined based on whether there is a location on track i where a link failure has occurred:

[0020] If there is no location in track i where a link failure has occurred, then the link failure range in track i will be... Recorded as ;

[0021] If there is a location in track i where a link failure occurs, then let the size of the link failure range in track i be . Calculation track

[0022] Channel i link fault range :

[0023] Furthermore, the calculation of the location and duration of all faulty links first involves obtaining the current time of track 1.

[0024] During the journey, the true perimeter angle of the inter-satellite link established between satellite number 1 and satellite number 2. Furthermore, for any orbit i, calculate the relationship between satellite number j and satellite numbered j. True perimeter angle of inter-satellite links established between satellites : Iterate through the set of link failure ranges again Each element in ,like ,and Then, the satellite numbered j in orbit i and the satellite numbered j... If the inter-satellite link established between the satellites fails, the location of all failed links is obtained after traversal, and the duration of the failure is calculated based on the geocentric gravitational constant, the mass and radius of the Earth, the satellite orbital altitude, and the true anomaly angle at the intersection of the projection of sunlight in the i-th orbital plane and orbit i.

[0025] Furthermore, the satellite autonomously avoids links based on the scope and duration of the link failure. This is achieved by first calculating the required avoidance time based on the size of the link failure range in orbit i. Then, the satellites in the i-th orbit will be positioned according to their established inter-satellite links. Just before entering the link failure area During this period, link avoidance should be initiated in advance, and data transmission channels should be shut down to avoid interference from solar outages on communication; avoidance After the time has passed, prepare in advance for link restoration and re-establish inter-satellite links.

[0026] 2. An inter-satellite link failure avoidance system based on time-quantitative calculation under solar interference effect, characterized in that it includes:

[0027] Initialization module: Used to initialize constellation parameters, establish the J2000.0 geocentric inertial coordinate system, and determine the position of satellites at any given time;

[0028] Right Ascension and Declination Calculation Module: Used to calculate the right ascension of the Sun. and declination ;

[0029] Judgment module: Used to determine whether there is a link failure location in the track;

[0030] Fault calculation module: used to calculate the link fault range, link fault location, and link fault duration;

[0031] Fault avoidance module: Used for autonomous link avoidance to prevent solar interference with communication.

[0032] Compared with the prior art, the present invention has the following advantages:

[0033] Firstly, this invention determines whether a link in the same orbit has failed by calculating the angle between sunlight and the satellite orbital plane. Compared with the existing technology that calculates the angle between sunlight and each satellite link, this reduces computational overhead and improves response speed.

[0034] Secondly, by solving for the region where the link failure occurs and calculating the duration of the link failure based on the actual position of the satellite, this invention can quickly and efficiently determine the region where the satellite constellation network experiences a link failure under the influence of solar interference and the duration of the failure.

[0035] Thirdly, because this invention quantitatively calculates the duration of link failures, it can guide satellites to efficiently avoid solar interference, thereby maximizing the operational efficiency and reliability of satellite links while ensuring that communication is not affected by solar interference. Attached Figure Description

[0036] Figure 1 This is a flowchart illustrating the implementation of the inter-satellite link fault avoidance method based on time-quantitative calculation under the solar interference effect of this invention.

[0037] Figure 2 This is a schematic diagram of the coordinate system and orbital parameters established in the method of this invention;

[0038] Figure 3 This is a schematic diagram of link failure analysis in the method of the present invention;

[0039] Figure 4 This is a block diagram of the inter-satellite link fault avoidance system based on time-quantitative calculation under the solar interference effect of the present invention;

[0040] Figure 5 This is a comparison chart of the duration of each track link failure obtained using the present invention and existing link failure analysis methods, respectively.

[0041] Figure 6 The graph shows the program execution time results for the duration of each track link failure, obtained using the present invention and existing link failure analysis methods, respectively. Detailed Implementation

[0042] To enable those skilled in the art to better understand the present invention, the technical solutions and effects of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the present invention and not all of the embodiments. Based on the embodiments of the present invention, other embodiments obtained by those skilled in the art without creative effort should all fall within the protection scope of the present invention.

[0043] This example is implemented based on a satellite network, analyzing link failures by examining the relationship between sunlight and each orbital plane.

[0044] Example 1: Inter-satellite link fault avoidance method based on time-quantitative calculation under solar interference effect

[0045] Reference Figure 1 The implementation steps of this example include the following:

[0046] Step 1: Initialize constellation parameters and establish the J2000.0 geocentric inertial coordinate system to determine the satellite's position at any given time.

[0047] Reference Figure 2 The implementation of this step is as follows:

[0048] 1.1) Initialize constellation parameters, including orbital altitude h, number of orbits P, number of satellites per orbit S, orbital inclination I, and phase factor F;

[0049] 1.2) Establish the J2000.0 geocentric inertial coordinate system: This coordinate system has the Earth's center as the origin, the X-axis points to the vernal equinox, the Z-axis points to the North Pole along the direction of the Earth's rotation axis, and the Y-axis is obtained according to the right-hand rule;

[0050] 1.3) Draw the line connecting the satellite and the Earth's center O, and denote the angle between this line and the XOY plane as the satellite's elevation angle. , The angle between the projection of the connecting line onto the XOY axis and the positive X-axis is denoted as the azimuth angle. , ;

[0051] 1.4) The right ascension of the ascending node of the satellite orbit is denoted as... , The true perimeter of the satellite is denoted as , ,

[0052] 1.5) According to the satellite The parameters can determine the satellite's position at any given time.

[0053] Step 2: Initialize the time t to be calculated and calculate the right ascension of the sun. declination .

[0054] 2.1) Convert time t to Julian day:

[0055] The Julian Day is an astronomical method for calculating time in consecutive days. It is mainly used in the fields of astronomy and aerospace, and is the standard time representation method widely used in these fields. It can also be used in scenarios such as electronic communication and computer systems that require high-precision time synchronization.

[0056] Julian Days (JD) can be calculated using the following formula:

[0057] For Gregorian calendar dates, let Y, M, and D represent the year, month, and day, respectively, with the decimal part representing the hour, minute, and second. Adjust Y and M according to the value of month M. Then let , Otherwise, remain unchanged and calculate the Gregorian calendar correction term. Thus, the Julian Daily reported:

[0058] ;

[0059] 2.2) Calculate the Julian century number T:

[0060] The Julian century is a unit of time, primarily used for Earth's rotation and coordinate transformations. Using 12:00 noon on January 1, 2000 as the reference point, the number of Julian centuries is calculated. ;

[0061] 2.3) Calculate the solar geometric mean ecliptic longitude L:

[0062] The geometric mean ecliptic longitude of the Sun is the average ecliptic longitude of the Sun from a geocentric perspective. It is measured along the ecliptic from the mean vernal equinox, excluding periodic terms caused by orbital eclipse, as well as corrections for nutation, aberration, etc. The calculation formula is:

[0063] ;

[0064] 2.4) Calculate the solar mean apogee angle g:

[0065] The solar mean aperimeter angle is the angle that increases with a uniform angular velocity starting from perihelion. The formula is: ;

[0066] 2.5) Calculate the ecliptic longitude correction term C:

[0067] The ecliptic longitude correction term is used to reflect the non-uniformity caused by the ellipticity of the Earth's revolution around the sun, and its calculation formula is as follows: ;

[0068] 2.6) Calculate the true ecliptic longitude of the sun. :

[0069] The true ecliptic longitude of the sun is the geometric ecliptic longitude after ellipticity correction, and the calculation formula is: ;

[0070] 2.7) Calculate the obliquity of the ecliptic. :

[0071] The obliquity of the ecliptic is the angle between the Earth's equatorial plane and the ecliptic plane, calculated using the following formula: ;

[0072] 2.8) Based on the true ecliptic longitude of the sun and the obliquity of the ecliptic Calculate the right ascension of the sun and declination

[0073] ,

[0074] .

[0075] Step 3: Calculate the angle between sunlight and the orbital plane of each satellite based on the constellation parameters and the right ascension and declination of the sun.

[0076] Reference Figure 3 The implementation of this step includes the following:

[0077] 3.1) Let the sphere with Earth's center O as its center and the satellite's orbital altitude as its radius be denoted as the constellation sphere. Let S be the point where sunlight is directly overhead on the constellation sphere, and let its corresponding right ascension be _____. Declination is ;

[0078] 3.2) For satellite orbit i, draw a perpendicular line from point S to the orbital plane; the intersection point is... ,extend Intersection of orbital plane and point , The true nearest angle at point is ,set up The angle between the plane and the track is ,Should It is also the angle between sunlight and the satellite's orbital plane, in which P is the number of orbitals;

[0079] 3.3) The plane perpendicular to the equatorial plane and passing through point S and the Earth's center is denoted as the right ascension plane. This right ascension plane intersects the orbital plane at point S. ,exist azimuth angle of the satellite Angle of elevation is The true nearest angle is ,but and The included angle between them is ;

[0080] 3.4) Calculate the angle between sunlight and the orbit of the i-th satellite. Where I is the orbital inclination angle;

[0081] 3.5) Repeat steps 3.2) to 3.4) to obtain the angle between sunlight and each satellite orbit.

[0082] Step 4: Determine if there are any link failure locations in the track, and calculate the link failure range for each track.

[0083] 4.1) Traverse each satellite orbit i and calculate the angle between the sunlight and the orbit. ,in P is the number of orbitals;

[0084] 4.2) Let the critical angle at which sunlight causes the inter-satellite link to be interrupted be... The angle between sunlight and the orbit With this critical angle By comparison, a P-dimensional set of link failure ranges is obtained. :

[0085] like Then there is a location on track i where a link failure occurs. Let the range of link failures on track i be large:

[0086] ,

[0087] The area where the track malfunctioned was calculated. ;

[0088] ,

[0089] Otherwise, if there is no location of link failure in track i, then the range of link failure in track i is... ;

[0090] Step 5: Calculate the location and duration of all failed links.

[0091] 5.1) Obtain the true perimeter angle of the inter-satellite link established between satellite number 1 and satellite number 2 in orbit 1 at the current time. ;

[0092] 5.2) For any orbit i, calculate the relationship between the satellite numbered j and the satellite numbered j. True perimeter angle of inter-satellite links established between satellites :

[0093] ,

[0094] Where P is the number of orbits, S is the number of satellites per orbit, and F is the phase factor;

[0095] 5.3) Traverse the set of link fault ranges Each element in , ,and Then, in orbit i, the satellite numbered j and the satellite numbered j... The inter-satellite links established between the satellites failed, and the locations of all failed links were obtained by traversing the network.

[0096] 5.4) The duration of the fault is calculated as follows:

[0097] ,

[0098] Where R represents the Earth's radius and h represents the satellite's orbital altitude. and They represent the gravitational constant and the mass of the Earth, respectively. Let be the true anterior angle at the intersection of the projection of sunlight onto the i-th orbital plane and orbit i.

[0099] Step 6: The satellite autonomously performs link avoidance.

[0100] 6.1) Based on the fault range of the link in track i Calculate the time required to avoid it. :

[0101] ;

[0102] 6.2) The satellites in the i-th orbit operate according to the inter-satellite links they have established. Just before entering the link failure area During this period, link avoidance should be initiated in advance, and data transmission channels should be shut down to avoid interference from solar outages on communication;

[0103] 6.3) In circumventing After the time has passed, prepare in advance for link restoration and re-establish inter-satellite links.

[0104] It should be noted that the flowchart representations or method representations of the above embodiments can be understood as representing code modules, fragments, or portions comprising one or more executable instructions configured to implement a specific logical function or process. This invention is not limited to the disclosed preferred embodiments, and its implementation may not follow the order shown or discussed. That is, the step numbers in this example and claims are only for clear description of the embodiments of the invention and for ease of understanding, and their order is not limited.

[0105] Implementation 2: Inter-satellite link failure avoidance system based on time-quantitative calculation under solar interference effect.

[0106] Reference Figure 4 This example includes: initialization module 1, right ascension and declination calculation module 2, judgment module 3, fault calculation module 4, and fault avoidance module 5. Fault calculation module 4 includes: fault range calculation submodule 41, fault location calculation submodule 42, and fault duration calculation submodule 43. The working principle of the entire system is as follows:

[0107] The initialization module 1 is used to initialize constellation parameters, establish the J2000.0 geocentric inertial coordinate system and determine the position of the satellite at any time; and transmit the satellite's position information and orbit information to the judgment module 3 and the fault calculation module 4.

[0108] The right ascension and declination calculation module 2 is used to calculate the right ascension of the sun. and declination Convert time t to Julian day and calculate Julian century number, then obtain the obliquity of the ecliptic and the true ecliptic longitude of the sun, finally calculate the right ascension and declination of the sun, and transmit the right ascension and declination of the sun to the judgment module 3;

[0109] The judgment module 3 is used to determine whether there is a link fault location in the orbit. It calculates the angle between sunlight and satellite orbit based on the right ascension and declination of the sun and satellite orbit information. Based on the relationship between this angle and the critical angle at which sunlight causes the inter-satellite link to be interrupted, it obtains the result of whether there is a fault location in the orbit and transmits this result to the fault calculation module 4.

[0110] The fault calculation module 4 is used to calculate the link fault range, link fault location, and link fault duration. The fault range calculation submodule 41 calculates the range of the faulty link based on the angle between sunlight and the satellite orbit and the critical angle at which sunlight causes inter-satellite link interruption, and transmits the result to the fault location calculation submodule 42 and the fault duration calculation submodule 43. The fault location calculation submodule 42 calculates the location of the faulty link based on the link fault range and the location of the inter-satellite link, and transmits the location of the faulty link to the fault duration calculation submodule 43. The fault duration calculation submodule 43 calculates the duration of the link fault based on the link fault range and the location of the faulty link, and transmits the result to the fault avoidance module 5.

[0111] The fault avoidance module 5 is used for satellites to autonomously avoid links. When a satellite is about to enter a link fault area, it closes the data transmission channel in advance. When a satellite is about to leave a link fault area, it prepares for link recovery in advance and re-establishes the inter-satellite link.

[0112] It should be noted that the above functional modules can be implemented, in whole or in part, through software, hardware, firmware, or any combination thereof. When implemented in software, they can be implemented, in whole or in part, as program instruction products. A program instruction product includes one or a set of program instructions. When the program instructions are loaded and executed on a computer, the described process or function is generated, in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The program instructions can be stored in a computer-readable and writable storage medium, or transferred from one computer's readable and writable storage medium to another.

[0113] The direct coupling or communication connections between the modules shown or discussed in this embodiment can be achieved through indirect coupling or communication connections via interfaces, devices, or modules. The various functional modules and sub-modules in this embodiment can dynamically reside within a single processing unit, or each module can exist physically independently, or two or more modules can dynamically reside within a single processing unit. When these dynamic components are implemented as software functional modules and sold or used as independent products, they can also be stored in a computer-readable and writable storage medium. This storage medium can be a memory, disk, or optical disc, etc.

[0114] The effects of this invention can be further illustrated by the following simulation results:

[0115] I. Simulation Conditions

[0116] The method designed in this invention was implemented using the simulation software MATLAB, and the existing method was reproduced. The device parameters were a 12th Gen Intel(R) Core(TM) i5-12400, 2.50 GHz, 32GB. The parameters used in the simulation scenario are shown in Table 1.

[0117] Table 1 Main Simulation Parameters

[0118]

[0119] II. Simulation Content

[0120] Simulation 1: Simulation of failure time of each track link

[0121] Using the present invention and existing methods for analyzing satellite network link failures under solar interference, the duration of link failures in various orbits under different constellation configurations was simulated. The results are as follows: Figure 5 As shown. The existing method involves determining the angle between sunlight and each inter-satellite link in real time. From... Figure 5 As can be seen, compared with existing methods, the method of the present invention obtains a maximum error of no more than 0.9% in the duration of each orbital fault under different constellation configurations.

[0122] Simulation 2: Program runtime simulation

[0123] Using the present invention and existing methods for analyzing satellite network link failures under solar interference, the runtime of the program was simulated under different constellation configurations. The results are as follows: Figure 6 As shown. From Figure 6 It is evident that, compared to existing methods, the method of this invention can significantly reduce the time required to calculate the failure status of the entire satellite network's co-orbit links, and the calculation time does not increase rapidly with the increase in the number of satellites.

[0124] The simulation results show that the method of the present invention can accurately calculate the duration of the link failure, thereby guiding the satellite to efficiently avoid solar interference, and can significantly reduce the calculation time without the calculation time increasing rapidly with the increase of satellite size.

Claims

1. A method for avoiding inter-satellite link failure under the effect of solar eclipse based on time quantitative calculation, characterized in that it comprises the following steps: S1) initializing constellation parameters, establishing a J2000.0 geocentric inertial coordinate system, and determining the position of a satellite at any time; S2) initialize the time t for which the calculation is required and calculate the right ascension , declination of the sun; S3) calculating the angle between sunlight and the orbital plane of each satellite according to the right ascension and declination of the sun and the constellation parameters, and comparing it with the critical angle of link damage to determine whether there is a link failure position in the orbit; S4) calculating the link failure range of each orbit according to the angle between sunlight and the orbital plane of each satellite; S5) calculating the position and duration of all failure links in each satellite orbit according to the link failure range and the position of the satellite; S6) the satellite autonomously avoids link according to the link failure range and the duration of the failure.

2. The method of claim 1, wherein, In the step S1), the constellation parameters are initialized, the J2000.0 geocentric inertial coordinate system is established, and the position of the satellite at any time is determined, which comprises the following steps: S1a) initializing the orbit height h, the number of orbits P, the number of satellites per orbit S, the orbit inclination I, and the phase factor F; S1b) establishing a J2000.0 geocentric inertial coordinate system with the center of the earth as the origin, the X axis pointing to the equinox point, the Z axis pointing to the north pole along the direction of the earth's rotation axis, and the Y axis obtained according to the right-hand rule; S1c) setting the satellite parameters: The line connecting the satellite and the earth center O is drawn, and the angle between the line and the XOY plane is recorded as the elevation angle of the satellite , ; The angle between the projection of the connection on XOY and the positive direction of the X axis is denoted as the azimuth angle , ; Let the right ascension of the ascending node of the satellite orbit be denoted by , ; Let the true anomaly of the satellite be denoted by ; S1d) determining the position of the satellite at any time according to the parameters These parameters determine the position of the satellite at any time.

3. The method of claim 1, wherein, S2) in which the time t is calculated, which is necessary for the initialization of the calculation of the right ascension , declination of the sun, which implementation comprises: S3a) converting the time t into Julian day and then calculating the Julian century number T; S3b) Calculate the obliquity of the ecliptic from the julian century number T and the true ecliptic longitude of the sun ; S3c) from the obliquity to the true ecliptic to calculate the ecliptic and the declination : ， 。 4. The method of claim 1, wherein, In step S3), the angle between sunlight and the orbital plane of each satellite is calculated, which is implemented as follows: S3a) the sphere with the satellite orbit height as the radius and with the earth center O as the sphere center is recorded as the constellation sphere, the direct point of sunlight on the constellation sphere is recorded as S, and the corresponding right ascension is , and the declination is ; (S3b) For satellite orbit i, draw a perpendicular line from point S to the orbital plane; the intersection point is... ,extend Intersection of orbital plane and point , The true nearest angle at point is ,set up The angle between the plane and the track is ,Should It is also the angle between sunlight and the satellite's orbital plane, where P is the number of orbitals; S3c) let the plane perpendicular to the equatorial plane and passing through the S point and the Earth's center be called the right ascension plane, which intersects the orbital plane at the point , at , the azimuth of the satellite , the elevation angle is , the true anomaly is , , the angle between , and ; S3d) calculating the angle of the sunlight with the i-th satellite orbit where I is the orbit inclination; S3e) repeating steps S3b) ~ S3d) to obtain the angle between sunlight and the orbital plane of each satellite.

5. The method of claim 1, wherein, In step S3), whether there is a link failure position in the orbit is determined, which is implemented as follows: Let the critical angle at which the sunlight causes the interruption of the inter-satellite link be The angle between the sunlight and the satellite orbit i is compared with the critical angle at which the sunlight causes the interruption of the inter-satellite link. If then the i orbit exists a position of link failure; Otherwise, there is no link failure position in the orbit i.

6. The method of claim 1, wherein, In step S4), the link failure range is calculated according to whether there is a link failure position in the orbit i: If there is no link failure position in the track i, the link failure range in the track i is recorded as denoted as ; If there is a link fault position in track i, let the size of the link fault range in track i be , and calculate the link fault range in track i : ， ， wherein is the critical angle for link outage, is the angle between the sun and the satellite orbit i, is the true anomaly of the intersection of the projection of the sun in the i-th orbit plane and the orbit i at the point of intersection.

7. The method of claim 1, wherein, In step S5), the position and duration of all failure links are calculated, which comprises the following steps: S5a) Acquire the true anomaly of the inter-satellite link established between the satellite numbered 1 and the satellite numbered 2 in the first orbit at the current time ; S5b) For any orbit i, calculate the true anomaly of the inter-satellite link established between the satellite numbered j and the satellite numbered :​ ， Wherein, P is the number of orbits, S is the number of satellites per orbit, and F is the phase factor; S5c) iterate over the set of link failure ranges each element of the set if and then in the orbit i the inter-satellite link between the satellite with number j and the satellite with number fails, iterate over all failed links. In step S6), the satellite autonomously avoids link according to the link failure range and the duration of the failure, which comprises the following steps: ， wherein represents the Earth's mass, R represents the Earth's radius, h represents the satellite's orbital altitude, represents the Earth's mass, R represents the Earth's radius, h represents the satellite's orbital altitude, is the true anomaly of the projection of the sun's light in the i-th orbital plane at the intersection of the i-th orbit.

8. The method of claim 1, wherein, 9. A system for avoiding inter-satellite link failure under the effect of solar eclipse based on time quantitative calculation, characterized in that it comprises: S6a) Calculate the time needed to avoid according to the size of the failure range of the link in track i : ， wherein is the range size of the link failure in orbit i, and respectively represent the gravitational constant of the earth and the mass of the earth, R represents the radius of the earth, and h represents the orbit height of the satellite; S6b) the position in which the satellite in the i-th orbit operates according to the inter-satellite link it has established When entering the link failure area , the link avoidance is started in advance, the data transmission channel is closed, and the interference of the sun on the communication is avoided. S6c) circumvention After a certain time, the link recovery preparation is made in advance, and the inter-satellite link is re-established. an initialization module for initializing constellation parameters, establishing a J2000.0 geocentric inertial coordinate system, and determining the position of a satellite at any time; a judgment module for determining whether there is a link failure position in the orbit; Right ascension and declination calculation module: for calculating the right ascension and declination of the sun and declination ; a failure calculation module for calculating the link failure range, the link failure position, and the link failure duration; a failure avoidance module for autonomously avoiding link to avoid the interference of solar eclipse on communication.

10. The system according to claim 9, characterized in that the failure calculation module comprises: a failure range calculation submodule for calculating the range of failure links according to the angle between sunlight and the orbital plane of the satellite and the critical angle of sunlight causing inter-satellite link interruption; a failure position calculation submodule for calculating the position of failure links according to the link failure range and the position of inter-satellite link. ​ The fault duration calculation submodule is configured to calculate the duration of the link fault according to the link fault range and the link position. The fault duration calculation submodule is configured to calculate the duration of the link fault according to the link fault range and the link position.

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