Low-orbit inclined orbit constellation network routing method

Abstract

The invention relates to a low-orbit inclined orbit constellation network routing method, which comprises the following steps of: 1, estimating communication states of all different-orbit inter-satellite links by obtaining connectable duration estimation of a single different-orbit inter-satellite link and obtaining a communication state switching moment offset matrix of all different-orbit inter-satellite links; step 2, the communication states of all different-orbit inter-satellite links are estimated; according to the method, the on-off states of all different-orbit inter-satellite links in the whole constellation are estimated by utilizing an inter-satellite distance measurement result and a periodic rule of constellation system motion, and the residual connectable duration of the different-orbit inter-satellite links is used as an important parameter for evaluating the link value; according to the constellation network routing method based on the complete constellation network connection relation table and the link value table, the problems of cross-orbit communication time delay and packet loss rate increase caused by sudden disconnection of different-orbit inter-satellite links are effectively avoided, and the difficulty caused by constellation network topology change to low-orbit inclined-orbit constellation network routing is overcome.

Description

Technical Field

[0001] The present application relates to the technical field of low-orbit satellite constellation network routing, and in particular to a low-orbit inclined orbit constellation network routing method. Background Art

[0002] Low-orbit satellite communication constellations are the biggest hotspot in the current satellite research and application fields. Communication networks based on satellite constellations will become an important part of the future global network. The constellation network routing algorithm is the key to realizing constellation network communication. The difficulty of its design lies in the fact that the on-off status of inter-orbit satellite links is constantly changing, which leads to the constant change of constellation network topology. If the inter-orbit satellite links are disconnected and cannot be discovered in time, the delay of cross-orbit communication frame transmission will increase, and even communication frame loss will occur.

[0003] There are roughly three types of routing algorithms currently applied to constellation networks, namely snapshot-based routing algorithms, virtual node-based routing algorithms, and routing algorithms derived from mobile Ad Hoc networks. Among them, snapshot-based routing algorithms are mainly applied to polar orbit constellations and are not applicable to inclined orbit constellations. Similarly, virtual node-based routing algorithms are also mainly applied to polar orbit constellations, and are only applicable to constellations with uniform satellite distribution, not to constellations with uneven satellite distribution. For routing algorithms derived from mobile Ad Hoc networks, although the satellite nodes in constellation networks are mobile and the network topology is changeable, which is consistent with the characteristics of mobile Ad Hoc networks, the satellite nodes in constellation networks are sparsely distributed, the distance between satellites is far, and the signal propagation delay is large, so the routing algorithms of mobile Ad Hoc networks are usually not applied to constellation networks. The ideal effect is not achieved. Moreover, the routing algorithms derived from mobile Ad Hoc networks cannot fully utilize the periodic characteristics of the switching of the on-off state of inter-satellite links and the changes in network topology in different orbits when applied to constellation networks. Therefore, the performance of such routing algorithms in constellation networks needs to be improved. Summary of the invention

[0004] In order to solve the problem of large delay and high packet loss rate in cross-orbit transmission of communication frames caused by changes in the connectivity status of inter-orbit links in different orbits during cross-orbit routing of existing constellation networks proposed in the above background technology, the present application provides a low-orbit inclined orbit constellation network routing method.

[0005] The present application provides a low-orbit inclined orbit constellation network routing method using the following technical solutions:

[0006] A low-orbit inclined orbit constellation network routing method, comprising the following steps:

[0007] Step 1: By estimating the connectable duration of a single inter-satellite link and obtaining a connection state switching time offset matrix of all inter-satellite links, the connectivity state of all inter-satellite links is estimated;

[0008] Step 2: Obtain a constellation network connection relationship table and a constellation network link value index table through the estimated connectivity status of all inter-satellite links in different orbits;

[0009] Step 3: According to the constellation network connection relationship table and the constellation network link value table, select the optimal route for information transmission between any two nodes within the constellation range.

[0010] By adopting the above technical solution, the whole process management from link state estimation to optimal route selection is realized in steps. In step one, by accurately estimating the connectivity time and connectivity state switching time of the off-orbit link, a reliable basic data is laid for the subsequent steps; in step two, by comprehensively considering the connectivity state and value index of the links in the constellation network, a constellation network connection relationship table and a constellation network link value table are established, which provides a comprehensive evaluation standard for route selection; in the third step, the efficiency of information transmission is maximized by selecting the optimal path. The overall method is suitable for low-orbit constellation networks with frequent dynamic continuity changes, which improves the information transmission performance and communication efficiency of the constellation system, and can adapt to the needs of dynamic changes in network topology.

[0011] Optionally, in step one, the method for estimating the connectivity duration of a single off-orbit inter-satellite link is: based on the close connection between the distance between off-orbit satellites, the sign of the inter-satellite relative velocity and the connectivity of the corresponding off-orbit inter-satellite link, the inter-satellite distance and relative velocity measurement results between a connectable off-orbit satellite are used to estimate the duration of the connectivity state of the off-orbit inter-satellite link.

[0012] By adopting the above technical solution, the correlation between link connectivity status and orbital parameters is scientifically revealed. This method is based on the measured distance and speed data, and can dynamically calculate the continuous connectivity time of the link, effectively avoiding the error problem caused by over-reliance on empirical models in traditional methods. At the same time, this estimation method is more adaptable to complex inclined orbit constellations, and can provide accurate duration prediction for dynamic routing optimization, improving the stability and reliability of the entire network.

[0013] Optionally, in step 1, the method for obtaining the connection state switching time offset matrix of all inter-orbital satellite links includes the following steps:

[0014] S1. According to the periodicity of the motion of the constellation system and the distribution law of inter-satellite links in different orbits, the moment when the connection state of all inter-satellite links in different orbits switches within one orbital period is analyzed;

[0015] S2. Taking one of the links as a reference, determine the time offset of the time when the connectivity state of all inter-orbital satellite links switches relative to the time when the connectivity state of the benchmark inter-orbital satellite link switches, so as to obtain the constellation network inter-orbital satellite link connectivity state switching time offset matrix.

[0016] By adopting the above technical solution, the management difficulty of dynamic links is simplified, and a reliable basis is provided for the connectivity status prediction and routing optimization of the constellation network. Especially in high-density constellation deployment, the stability and communication efficiency of the network can be significantly improved.

[0017] Optionally, in step 1, the connectivity status of all inter-satellite links in different orbits is the connectivity status at the current moment or within a certain time range in the future.

[0018] By adopting the above technical solution, the acquisition of real-time or predictive connectivity status provides the possibility of dynamic adjustment for subsequent route selection, which can effectively cope with the problem of frequent link changes in the constellation system and ensure the continuity and reliability of the information transmission path.

[0019] Optionally, in step 2, the method for obtaining the constellation network connection relationship table and the constellation network link value index table is:

[0020] According to the connectivity status of all inter-orbital links in the constellation network, the inter-orbital satellite connection relationship table of the constellation network at a specified time can be obtained. At the same time, the remaining connectable time of each inter-orbital satellite from the specified time can also be obtained, and the time is used as one of the parameters for evaluating the value index of the corresponding inter-orbital link to generate the inter-orbital link value index table;

[0021] The obtained constellation network different-orbit satellite connection relationship table is combined with the same-orbit satellite connection relationship table to generate a constellation network connection relationship table;

[0022] The obtained inter-orbital link value index table is combined with the inter-orbital link value index table to generate the constellation network link value index table.

[0023] By adopting the above technical solution, a comprehensive description of the network topology structure is achieved by constructing a connection relationship table and a link value index table of the constellation network. This method combines off-orbit links and on-orbit links to form a unified connection relationship table, which can accurately reflect the connection relationship between any nodes in the constellation. At the same time, by generating a value index table with the link connectivity time as the main parameter, the communication value of the link can be quantitatively evaluated, providing a reliable reference for route selection. This combined method has both a global perspective and local optimization capabilities, and can greatly improve the scientificity and rationality of route selection in a dynamic network environment.

[0024] Optionally, the inter-orbital link value index in the constellation network link value index table uses the link connectivity time as one of the evaluation parameters, and the inter-orbital link value index table is used as the basis for route selection, so that when the communication frame is transmitted across orbits, it gives priority to selecting the inter-orbital link that is currently connected and has a long remaining sustainable connectivity time as the inter-orbit transmission path.

[0025] By adopting the above technical solution, it is possible to give priority to links that are currently connected and have a longer remaining connectivity time for cross-track transmission, thereby reducing the transmission delay and data packet loss risks caused by frequent link switching.

[0026] Optionally, in step three, when selecting the optimal route for information transmission between any two nodes within the constellation, it is necessary to consider the time taken for the communication frame to be transmitted to a certain node in the path, as well as the changes in the on / off state and value index of the inter-orbital link during this period.

[0027] By adopting the above technical solution, the user selects the route for the communication frame not only based on the constellation network connection relationship table and link value table at a fixed time, but also considers the connection relationship and value index changes between satellites in different orbits during the transmission of the communication frame, and selects the best real-time route for the communication frame. This dynamic adjustment mechanism makes the route selection more accurate and effectively reduces the risk of transmission failure caused by sudden changes in link status or value changes.

[0028] Optionally, in step three, when selecting the optimal route for information transmission between any two nodes within the constellation range, it is necessary to select the optimal transmission path from the current node to the destination node according to the latest constellation network connection relationship table and link value table before each hop transmission to cope with abnormal changes in the constellation network connection relationship table or the link value index table caused by special circumstances.

[0029] Optionally, the special circumstances include sudden failure of a satellite and / or sudden interference with an intersatellite link.

[0030] By adopting the above technical solutions, not only the flexibility and adaptability of routing selection are improved, but also the transmission failure rate caused by abnormal changes is greatly reduced, further enhancing the stability and reliability of the low-orbit constellation network.

[0031] In summary, the present application includes at least one of the following beneficial technical effects:

[0032] The present invention utilizes inter-satellite ranging results and the periodic law of constellation system motion to estimate the on / off status of all inter-satellite links in the entire constellation, and uses the remaining connectable time of the inter-satellite links as an important parameter for evaluating link value. The constellation network routing method is implemented based on a complete constellation network connection relationship table and a link value table, which effectively avoids the problems of increased cross-orbit communication delay and packet loss rate caused by sudden disconnection of inter-satellite links in different orbits, and overcomes the difficulties caused by changes in constellation network topology to low-orbit inclined orbit constellation network routing. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 is the constellation configuration diagram of the present invention;

[0034] Figure 2 The present invention shows a curve of the distance between different orbital stars changing with time and a schematic diagram of the connectable windows;

[0035] Figure 3 This is a schematic diagram of the position relationship between the different orbital stars of the present invention;

[0036] Figure 4 The error curve of estimating the connectable duration of inter-satellite links in different orbits using inter-satellite ranging results at different times in the present invention;

[0037] Figure 5 This is a schematic diagram of the time periods during which different inter-orbit satellite links of orbit 1 and orbit 2 of the present invention can be connected;

[0038] Figure 6 It is a schematic diagram of the on-off state of all inter-satellite links in different orbits in an operation cycle of a constellation system of the present invention;

[0039] Figure 7 This is the simulation result of inter-track communication delay when the method of the present invention is not used;

[0040] Figure 8 The simulation result of inter-track communication delay when using the method of the present invention;

[0041] Fig. 9 It is a flow chart of the present invention. DETAILED DESCRIPTION

[0042] The present application is further described in detail below in conjunction with the accompanying drawings.

[0043] The embodiment of the present application discloses a low-orbit inclined orbit constellation network routing method, which includes the following three steps.

[0044] Step 1: By obtaining an estimated connectivity time of a single inter-satellite link and obtaining a connectivity state switching time offset matrix of all inter-satellite links, the connectivity state of all inter-satellite links is estimated. The connectivity state of all inter-satellite links is the connectivity state at the current time or within a certain time range in the future.

[0045] Specifically, the method for estimating the connectivity duration of a single off-orbit inter-satellite link is as follows: based on the close relationship between the distance between off-orbit satellites, the sign of the inter-satellite relative velocity and the connectivity of the corresponding off-orbit inter-satellite link, the inter-satellite distance and relative velocity measurement results between a connectable off-orbit satellite are used to estimate the duration of the connectivity state of the off-orbit inter-satellite link.

[0046] Specifically, Fig. 9 As shown, the method for obtaining the connection state switching time offset matrix of all inter-satellite links in different orbits includes the following steps:

[0047] S1. According to the periodicity of the motion of the constellation system and the distribution law of inter-satellite links in different orbits, the moment when the connection state of all inter-satellite links in different orbits switches within one orbital period is analyzed;

[0048] S2. Taking one of the links as a reference, determine the time offset of the time when the connectivity state of all inter-orbital satellite links switches relative to the time when the connectivity state of the benchmark inter-orbital satellite link switches, so as to obtain the constellation network inter-orbital satellite link connectivity state switching time offset matrix.

[0049] Step 2: Obtain a constellation network connection relationship table and a constellation network link value index table by estimating the connectivity status of all inter-satellite links in different orbits.

[0050] Specifically, the method for obtaining the constellation network connection relationship table and the constellation network link value index table is:

[0051] According to the connectivity status of all inter-orbital links in the constellation network, the inter-orbital satellite connection relationship table of the constellation network at a specified time can be obtained. At the same time, the remaining connectable time of each inter-orbital satellite from the specified time can also be obtained, and the time is used as one of the parameters for evaluating the value index of the corresponding inter-orbital link to generate the inter-orbital link value index table;

[0052] The obtained constellation network different-orbit satellite connection relationship table is combined with the same-orbit satellite connection relationship table to generate a constellation network connection relationship table;

[0053] The obtained inter-orbital link value index table is combined with the inter-orbital link value index table to generate the constellation network link value index table.

[0054] Step 3: According to the constellation network connection relationship table and the constellation network link value table, select the optimal route for information transmission between any two nodes within the constellation range.

[0055] Specifically, the inter-orbital inter-satellite link value index in the constellation network link value index table uses the link connectivity time as one of the evaluation parameters, and uses the inter-orbital inter-satellite link value index table as the basis for route selection, so that when the communication frame is transmitted across orbits, it gives priority to selecting the inter-orbital inter-satellite link that is currently connected and has a long remaining sustainable connectivity time as the inter-orbital transmission path. The purpose is to avoid sending the communication frame to the satellite that cannot currently establish the inter-orbital inter-satellite link or the inter-orbital inter-satellite link is about to be disconnected, thereby reducing the delay and packet loss rate of the cross-orbit transmission of the communication frame.

[0056] Specifically, in step 3, when selecting the optimal route for information transmission between any two nodes within the constellation, it is necessary to consider the time it takes for the communication frame to be transmitted to a certain node in the path, as well as the change in the on / off state of the inter-satellite link and the change in the value index during this period. That is, it is not just based on the constellation network connection relationship table and link value table at a fixed time to select a route for the communication frame, but it takes into account the change in the inter-satellite connection relationship and value index during the communication frame transmission process, and selects the best real-time route for the communication frame.

[0057] Specifically, in step 3, when selecting the optimal route for information transmission between any two nodes within the constellation range, not only the optimal route is selected for the communication frame before the first hop transmission, but the optimal transmission path from the current node to the destination node is selected according to the latest constellation network connection relationship table and link value table before each hop transmission, so as to cope with the abnormal changes of the constellation network connection relationship table or link value index table caused by special circumstances, and the special circumstances include sudden failure of the satellite and / or sudden interference of the intersatellite link. When no special circumstances occur, the optimal transmission path of the communication frame obtained at each intermediate node is part of the optimal transmission path selected for the communication frame at the source node.

[0058] In order to further illustrate this low-orbit inclined orbit constellation network routing method, a specific embodiment actually applied in the demonstration and verification task of the "Huanjiang No. 1" micro-nano satellite constellation network of Zhuji Huanjiang Laboratory is given below.

[0059] like Figure 1 As shown, the low-orbit inclined orbit constellation of this embodiment is composed of 50 satellites in 5 orbital planes, and 10 satellites are evenly distributed on each orbital plane, among which: Figure 1 The black dots in the figure represent satellites, and the lines represent satellite orbits, of which there are 5. Next, we first explain how to determine the remaining connectable time of the inter-satellite link in an inter-orbital satellite by using the inter-satellite distance measurement results and the sign of the inter-satellite relative velocity.

[0060] like Figure 2As shown, the intersatellite distance variation curve between two adjacent satellites in different orbits of this embodiment has the same period as the on-off state of the corresponding intersatellite link in different orbits. It shows that the on-off state of the intersatellite link in different orbits has a one-to-one correspondence with the interval in which the intersatellite distance is located. It means that, when the intersatellite distance is known, the current on-off state of the intersatellite link in different orbits can be estimated. Further observation shows that the interval in which the intersatellite link in different orbits is in a connected state is centered at the moment when the intersatellite distance reaches the maximum value. At the same time, in this interval, the intersatellite distance variation curve is symmetrical on the left and right. On the left side of the interval, the intersatellite distance gradually increases, indicating that the relative speed between the intersatellites is positive. On the right side of the interval, the intersatellite distance gradually decreases, indicating that the relative speed between the intersatellites is negative. Therefore, combined with the measured size of the intersatellite distance at the current moment and the sign of the relative motion speed between the intersatellites, the specific position of the intersatellite link in the visible interval can be determined, and then the length of time that the intersatellite link can remain connected can be determined.

[0061] like Figure 3 As shown, the distance between the satellites S1 and S2 in different orbits is equal to the vector The modulus, vector and The angle between , then, the distance between the stars in different orbits is (1).

[0062] and Phase with the orbital planes of the two satellites and The relationship between them is:

[0063] (2)

[0064] Among them, the two coefficients and equal,

[0065]

[0066] In the above formula, represents the orbital inclination, and The right ascension of the ascending node of the orbital plane of the two satellites respectively. and is a quantity that changes with time, so the distance between stars in different orbits is and With time Make connections.

[0067] According to formulas (1) and (2), we can get the following relationship:

[0068] (3)

[0069] make ,in represents the angular velocity of the satellite. Formula (3) represents the inter-satellite distance With time Theoretically, if the distance between stars in different orbits is known, the time position of the distance in the change cycle can be calculated by formula (3).

[0070] In this embodiment, the maximum length of the time window in which the inter-satellite link can be connected is 1510 s. At the same time, as mentioned above, the time window is symmetrical about the time when the inter-satellite distance reaches the maximum value. This means that when the inter-satellite distance reaches the maximum value, the time window in which the inter-satellite link can be connected has elapsed by 755 s. According to formula (3), when the inter-satellite distance reaches the maximum value, the calculation result is Therefore, if you use represents the time that has elapsed since the intersatellite link can be connected. Then,

[0071] (4)

[0072] in, represents the relative velocity between stars, is a sign function.

[0073] However, the inter-satellite distance measurement may produce deviations due to factors such as inter-satellite relative motion, equipment delay, forwarding delay, and ionospheric delay, which may lead to The estimation produces errors. Figure 4 The value of The estimated error size It can be seen that when the inter-satellite distance is close to the maximum value, The estimated error of The estimation error is less than 0.5 s, and the minimum estimation error is about 0.022 s. Therefore, it is necessary to avoid estimating when the intersatellite distance is close to the maximum value. .

[0074] like Figure 5 As shown in FIG. 1 , in the constellation of this embodiment, the change process of the on-off state of different inter-satellite links over time has similar periodicity. Specifically, Figure 5The time periods for establishing and disconnecting the five inter-satellite links on orbits 1 and 2 are given in the figure. In the vertical coordinate system, 1C5-2C4 represents the inter-satellite link between satellite C5 on orbit 1 and satellite C4 on orbit 2, and the other labels are similar. This means that there is a fixed time offset between the switching moments of the on-off states of different inter-satellite links. Figure 6 The time when the on-off state of each inter-satellite link changes within a constellation system operation cycle is given. The offset size matrix table of the on-off state switching time of different inter-satellite links in the constellation of this embodiment is shown in Table 1 below: Table 1

[0075]

[0076] In the above table, the two numbers (x, y) in each row of the first column represent the x orbit and the y orbit. In the corresponding row, the first sub-row represents the corresponding inter-orbital inter-satellite link, for example, mCn represents the Cn satellite on the m orbit. mCn-xCy represents the inter-orbital inter-satellite link between the Cn satellite on the m orbit and the Cy satellite on the x orbit; the second sub-row represents the offset between the time when the corresponding inter-orbital inter-satellite link is established and the time when the 1C1-2C5 inter-orbital inter-satellite link is established.

[0077] When the position of one of the intersatellite links in the on-off state change cycle at a specified time is known, the position of all other intersatellite links in their on-off state change cycle at the same time can be calculated according to the offset given in the table, that is, their on-off states can be inferred. If it is inferred that an intersatellite link in the off-orbit is in a connected state at a specified time, then it can also be calculated how long it will take for the intersatellite link to be disconnected. Conversely, if it is inferred that an intersatellite link in the off-orbit is in a disconnected state at a specified time, then it can be calculated how long it will take for the intersatellite link to be connected. The remaining connectable time of the intersatellite link can be used as one of the evaluation factors of the value index of the intersatellite link in the off-orbit, and used as a basis for cross-orbit routing selection.

[0078] The constellation network connection relationship table can be generated by combining the connection relationship of satellites in the same orbit and the connection relationship of satellites in different orbits. At the same time, the constellation network link value table can be generated by combining the inter-satellite link value index in the same orbit and the inter-satellite link value index in different orbits. The inter-satellite link value index is a comprehensive reflection of link reliability and latency, which can be determined by multi-dimensional parameters such as link bit error rate, interference, latency, etc. Combining the constellation network connection relationship table and the link value table, the constellation network routing function can be realized, and the optimal transmission path for communication frames can be selected within the entire constellation network.

[0079] As a comparison, Figure 7The delay of sending communication frames between satellites in two adjacent orbits when the "low-orbit inclined orbit constellation network routing method" of the present embodiment is not adopted in the constellation of the present embodiment is given. When the "low-orbit inclined orbit constellation network routing method" of the present embodiment is not adopted, it is assumed that each satellite node does not know the on-off status of the inter-orbital link between the current orbit and the adjacent orbit. Therefore, when sending a communication frame to a satellite in an adjacent orbit, it is first determined whether the current satellite can establish an inter-orbital link with the adjacent orbit. If yes, it is sent directly to the adjacent orbit. If not, it is sent along a fixed direction to the next satellite in the same orbit until the communication frame is sent to the satellite that can establish an inter-orbital link with the adjacent orbit.

[0080] Figure 8 The delay of sending communication frames between satellites in two adjacent orbits when the "low-orbit inclined orbit constellation network routing method" of this embodiment is adopted in the constellation of this embodiment is given. Figure 7 and Figure 8 It can be seen that after adopting the “low-orbit inclined orbit constellation network routing method” of this embodiment, the cross-orbit transmission delay of the communication frame has been greatly improved.

[0081] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A low-orbit inclined orbit constellation network routing method, characterized in that: The following steps are involved: Step 1: By estimating the connectable duration of a single inter-satellite link and obtaining a connection state switching time offset matrix of all inter-satellite links, the connectivity state of all inter-satellite links is estimated; Step 2: Obtain a constellation network connection relationship table and a constellation network link value index table through the estimated connectivity status of all inter-satellite links in different orbits; Step 3: According to the constellation network connection relationship table and the constellation network link value table, select the optimal route for information transmission between any two nodes within the constellation range.

2. A low-orbit inclined orbit constellation network routing method according to claim 1, characterized in that: In the step 1, the method for estimating the connectable duration of a single inter-satellite link is: based on the close relationship between the distance between the inter-satellite satellites, the sign of the inter-satellite relative velocity and the connectivity of the corresponding inter-satellite link, the inter-satellite distance and relative velocity measurement results between the connectable inter-satellite satellites are used to estimate the duration of the connectable state of the inter-satellite link.

3. A low-orbit inclined orbit constellation network routing method according to claim 1, characterized in that: In the step 1, the method for obtaining the connection state switching time offset matrix of all inter-orbital satellite links comprises the following steps: S1. According to the periodicity of the motion of the constellation system and the distribution law of inter-satellite links in different orbits, the moment when the connection state of all inter-satellite links in different orbits switches within one orbital period is analyzed; S2. Taking one of the links as a reference, determine the time offset of the time when the connectivity state of all inter-orbital satellite links switches relative to the time when the connectivity state of the benchmark inter-orbital satellite link switches, so as to obtain the constellation network inter-orbital satellite link connectivity state switching time offset matrix.

4. A low-orbit inclined orbit constellation network routing method according to claim 1, characterized in that: In the step 1, the connectivity status of all inter-satellite links in different orbits is the connectivity status at the current time or within a certain time range in the future.

5. A low-orbit inclined orbit constellation network routing method according to claim 1, characterized in that: In step 2, the method for obtaining the constellation network connection relationship table and the constellation network link value index table is: According to the connectivity status of all inter-orbital links in the constellation network, the inter-orbital satellite connection relationship table of the constellation network at a specified time can be obtained. At the same time, the remaining connectable time of each inter-orbital satellite from the specified time can also be obtained, and the time is used as one of the parameters for evaluating the value index of the corresponding inter-orbital link to generate the inter-orbital link value index table; The obtained constellation network different-orbit satellite connection relationship table is combined with the same-orbit satellite connection relationship table to generate a constellation network connection relationship table; The obtained inter-orbital link value index table is combined with the inter-orbital link value index table to generate the constellation network link value index table.

6. A low-orbit inclined orbit constellation network routing method according to claim 1, characterized in that: The inter-orbital inter-satellite link value index in the constellation network link value index table uses the link connectivity time as one of the evaluation parameters, and uses the inter-orbital inter-satellite link value index table as the basis for route selection, so that when communication frames are transmitted across orbits, they give priority to selecting the inter-orbital inter-satellite link that is currently connected and has a long remaining sustainable connectivity time as the inter-orbit transmission path.

7. A low-orbit inclined orbit constellation network routing method according to claim 1, characterized in that: In step 3, when selecting the optimal route for information transmission between any two nodes within the constellation, it is necessary to consider the time taken for the communication frame to be transmitted to a certain node in the path, as well as the changes in the on / off state and value index of the inter-satellite link in different orbits during this period.

8. A low-orbit inclined orbit constellation network routing method according to claim 1, characterized in that: In step 3, when selecting the optimal route for information transmission between any two nodes within the constellation range, it is necessary to select the optimal transmission path from the current node to the destination node according to the latest constellation network connection relationship table and link value table before each hop transmission to cope with abnormal changes in the constellation network connection relationship table or link value index table caused by special circumstances.

9. A low-orbit inclined orbit constellation network routing method according to claim 8, characterized in that: The special circumstances described include sudden failure of a satellite and / or sudden disturbance of an intersatellite link.

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