Low-orbit communication satellite two-dimensional switching system

Abstract

The invention discloses a low-orbit communication satellite two-dimensional switching system, and belongs to the technical field of low-orbit satellite communication. According to the system, a load monitoring unit, a route switching unit, an inter-satellite processing unit, an access network processing unit and a feed processing unit work cooperatively. The load monitoring unit calculates the relative position of the satellite and the gateway station, generates an antenna pointing angle and stores a gateway station position table; the route exchange unit completes information forwarding, route detection and flow statistics; the inter-satellite processing unit realizes signal processing and mode conversion, and adopts a phased-array antenna to support fast beam pointing; the access network processing unit processes a user signal and supports a multi-mode antenna; the feed processing unit adopts a right-handed circularly polarized antenna and is isolated from left-handed polarization of an inter-satellite link, so that same-frequency parallel transmission is realized. Through a two-dimensional cooperative control mechanism, an intelligent judgment algorithm and a ground-satellite cooperative transmission architecture, the reliability and the resource utilization rate of a satellite communication network are remarkably improved.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of low-orbit satellite communication, and particularly relates to a low-orbit communication satellite dual-dimension switching system. BACKGROUND

[0002] In recent years, the low-orbit satellite Internet has experienced explosive growth, and its strategic position in the global communication network has become increasingly prominent. However, this technical system faces multiple technical challenges in the process of landing application: on the one hand, the large-scale deployment demand of the satellite communication system is in sharp contradiction with the lag of inter-satellite communication stability guarantee technology; on the other hand, the exponential growth of the user scale is superimposed on the dramatic increase of satellite management data volume, and how to break through the satellite-ground communication capacity bottleneck has become the focus of industry research. In addition, the inter-satellite link lacks a dynamic load balancing mechanism, resulting in insufficient utilization of link resources; the traditional inter-satellite link switching scheme has problems such as high delay and poor reliability when the link transmission capacity decreases or the antenna alignment fails, which seriously restricts the system performance. SUMMARY

[0003] The application proposes a low-orbit communication satellite dual-dimension switching system to solve the above problems. The system constructs a communication resource intelligent scheduling system through the cooperative control mechanism of mode switching and path switching. The mode switching can dynamically convert the inter-satellite communication link into the satellite-ground feeder link to realize the elastic expansion of the satellite-ground communication capacity; the path switching can build a relay transmission channel through the ground switching matrix when the inter-satellite link is abnormal to ensure the seamless connection of the communication link.

[0004] The application achieves the above effects through the following technical scheme: A low-orbit communication satellite dual-dimension switching system comprises a load monitoring unit, a routing switching unit, an access network processing unit, a feeder processing unit and an inter-satellite processing unit. The load monitoring unit calculates the relative position vector of the satellite platform and the gateway station based on ephemeris data and real-time orbit parameters, and predicts the stable link establishment time window; generates the three-dimensional pointing angle of the inter-satellite antenna in combination with the orbit parameters of the neighboring satellites to realize beam alignment; supports real-time updating on orbit through the built-in global gateway station position table, and the load monitoring unit generates instructions to interact with the gateway station according to the satellite load working state and the working parameters of the routing switching unit, the access network processing unit, the feeder processing unit and the inter-satellite processing unit to realize information alignment of the satellite-ground system; The routing switching unit realizes efficient information forwarding based on a dynamic routing table, supports inter-satellite and inter-satellite-ground routing detection; at the same time, periodically sends routing detection packets to monitor the inter-satellite link connectivity and transmission quality in real time; in addition, the routing switching unit monitors the traffic of each inter-satellite processing unit in real time to provide data support for the dual-dimension switching strategy; The inter-satellite processing unit supports wireless signal transmission and reception and coding and modulation of the inter-satellite link, and realizes mode conversion in the two-dimensional switching; The access network processing unit is used for completing baseband processing and wireless transmission and reception of access signals and service data; meanwhile, supports three modes of antenna control, i.e., the hop-beam polling, the gaze mode and the agile mode; the hop-beam polling is used for wideband user competition for network access, and improves multi-user access efficiency; the gaze mode and the agile mode are used for providing directional high-speed transmission for key users or Internet services when the access beam traffic is low; The feeder processing unit supports high-speed data transmission and reception between the ground gateway station and the satellite, and provides physical layer support for the feeder link in mode switching.

[0005] Further, based on the dynamic configuration capability of the satellite payload, the inter-satellite / inter-satellite mode switching and the fault path switching are organically combined to construct a three-dimensional switching network with multi-dimensional resource scheduling capability; the link state is sensed in real time through the payload monitoring unit, mode conversion is automatically triggered to release the inter-satellite communication capacity in the traffic fluctuation scenario, and the transmission path adjustment is quickly started through the hop-beam in the link abnormality, forming a cooperative optimization system of capacity improvement and fault tolerance.

[0006] Further, the specific process of the inter-satellite / inter-satellite mode switching is as follows: Step 101, when the inter-satellite antenna of the A satellite is visible to the gateway station and the stable time exceeds the set minimum stable time, the traffic between the A satellite and the adjacent satellite B4 is less than the set traffic threshold, and the original data can be forwarded through other adjacent satellites B1, B2 or B3, the switching preparation process is entered; Step 102, before initiating the switching, the payload monitoring unit generates a control instruction which is sent to the gateway station through the feeder processing unit, and the gateway station completes the frequency converter, modem working parameter configuration and ground antenna pre-pointing according to the received instruction; Step 103, initiating the switching, the routing exchange unit reports the port to be disconnected state to the network controller of the gateway station through the feeder processing unit, and the network controller completes the routing table diffusion after convergence; Step 104, after the interface data of the A satellite and the adjacent satellite B4 completes the flow diversion, the payload monitoring unit calculates the beam angle according to the real-time parameters of the satellite and the position of the gateway station, and completes the pointing adjustment; the pointing is adjusted from the adjacent satellite B4 to the ground gateway station; Step 105, in the process of pointing to the gateway station, the payload monitoring unit switches the inter-satellite processing unit to the feeder mode, and the inter-satellite processing unit establishes the inter-satellite link synchronization through the pseudo-random sequence; Step 106, after link synchronization, the load monitoring unit generates instructions to inform the routing exchange unit to complete port switching, i.e., to inform the interface of the A star and the adjacent star B4 to be used as a feeder port, and then to complete routing probe updating and routing table diffusion; after all diffusion, the interstellar processing unit is used as a star-ground feeder, and the star continues to retain user network access functions; Step 107, after the A star has new users accessing the network, the access network processing unit completes the coverage of other adjacent stars B1, B2 and B3 through the routing exchange unit, and if the adjacent stars can cover the new users, cross-star switching is triggered; otherwise, the A star provides minimum service traffic to guarantee user business development; Step 108, when the A star is about to leave the gateway station, the ground network controller is informed to complete convergence and then perform routing table diffusion; Step 109, after the routing table diffusion is completed, the interstellar processing unit of the A star is restored to realize interstellar communication.

[0007] Further, the specific process of the fault path switching is as follows: Step 201, when the interstellar link error rate between the A star and the adjacent star B4 continuously exceeds the threshold, and the rate adaptation mechanism cannot meet the communication requirements; Step 202, the load monitoring unit calculates the gateway station visibility of the A star and the adjacent star B4 based on the real-time satellite orbit parameters and the gateway station parameter table, and the judgment principle is whether there are available gateway stations for the A star and the adjacent star B4, respectively; Step 203, if there are available gateway stations a and b4 for the A star and the adjacent star B4, respectively, the load monitoring unit generates control instructions according to the interstellar exchange unit state and sends them to the corresponding gateway stations; after receiving the instructions, the available gateway stations a and b4 complete the configuration of working parameters, including the configuration of ground frequency converters, the update of transparent switching network port configuration and the adaptation of modem parameters, synchronously; Step 204, after the ground parameter configuration is completed, the A star and the adjacent star B4 calculate the pointing angles of the antennas and send instructions; the interstellar processing unit controls the antenna to perform beam hopping based on the unified satellite clock in the data protection time slot, and points to the corresponding gateway stations, wherein the A star points to the available gateway station a, and the adjacent star B4 points to the available gateway station b4; Step 205, through the routing configuration of the ground switching matrix, the A star and the adjacent star B4 complete port connection through the star-ground-star relay channel; based on the known forwarding hop number, the data transmission path is optimized to realize zero-interruption transmission of services in the interstellar link fault state; Step 206, when any one of the A star and the adjacent star B4 is about to leave the gateway station, the A star and the adjacent star B4 inform the network controller of the gateway station of the disconnection message, and the network controller completes routing convergence and then performs routing table diffusion; Step 207, after diffusion is completed, the inter-satellite processing unit of both A star and adjacent star B4 restores to realize inter-satellite communication.

[0008] Further, by means of the inter-satellite antenna turning to the ground gateway station, a star-ground-star relay channel is constructed by using the ground transparent switching network, wherein the ground transparent switching network realizes transparent forwarding transmission of signals.

[0009] Compared with the prior art, the beneficial effects of the present application are: The present application proposes a dual-dimensional cooperative control mechanism, based on the dynamic configuration capability of satellite payload, organically combines the inter-satellite / inter-ground mode switching and the fault path switching, and constructs a three-dimensional switching network with multi-dimensional resource scheduling capability. The mechanism realizes real-time sensing of link state through the payload monitoring unit, automatically triggers mode conversion to release the inter-ground communication capacity in the traffic fluctuation scenario, and at the same time starts the path re-routing strategy when the link is abnormal, forming a cooperative optimization system of capacity improvement and fault tolerance.

[0010] The present application proposes an intelligent decision algorithm architecture, based on the dual criterion triggering mechanism of traffic threshold and bit error rate, by real-time monitoring of inter-satellite link traffic load (such as bandwidth utilization) and transmission quality (such as bit error rate mutation), realizes the automatic and accurate determination of the switching triggering condition. The algorithm has a built-in dynamic threshold adaptive module, which can automatically optimize the decision threshold according to the orbit period and the business model, avoid false triggering and missed judgment, and ensure the real-time and accuracy of the switching strategy.

[0011] The present application proposes a ground-satellite cooperative transmission architecture, introduces the relay transmission technology of ground microwave switching matrix and optical fiber network, breaks through the topological constraint and transmission distance limit of traditional inter-satellite link. When the inter-satellite link fails, by means of the inter-satellite antenna turning to the ground gateway station, the microwave switching matrix and the ground optical fiber network are used to construct a "star-ground-star" relay channel, and by means of the gain advantage of large aperture antenna of the ground station and the low delay characteristics of the optical fiber network, the high-speed and stable transmission of cross-satellite data is realized.

[0012] This scheme makes the satellite communication system have significant performance advantages: in the traffic load fluctuation scenario of the payload, the inter-satellite / inter-ground mode switching is realized to improve the inter-ground communication capacity by 100%, effectively dealing with the data transmission demand brought by the explosive growth of users; without additional intervention of the bearer network, the service interruption time during link failure can be shortened to 100ns level, which is significantly shorter than the s level time required for route convergence and diffusion in traditional switching scheme, significantly enhancing the reliability and resource utilization efficiency of the satellite communication network. BRIEF DESCRIPTION OF DRAWINGS

[0013] Figure 1 It is a schematic diagram of the connection relationship of the low-orbit satellite in the embodiment of the present application.

[0014] Figure 2Fig. 1 is a schematic diagram of mode switching and path switching in an embodiment of the present application. DETAILED DESCRIPTION

[0015] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and not used to limit the present application.

[0016] Reference Figure 1 and Figure 2 A low-orbit communication satellite dual-dimension switching system includes a load monitoring unit, a routing switching unit, an inter-satellite processing unit, an access network processing unit, and a feeder processing unit. The units work cooperatively to realize multi-dimension communication resource scheduling.

[0017] The load monitoring unit has the functions of accurately calculating the relative position vector of the satellite platform and the gateway station based on ephemeris data and real-time orbit parameters, predicting the stable link establishment time window, generating the three-dimensional pointing angle (azimuth angle, elevation angle) of the inter-satellite antenna in combination with the orbit parameters of neighboring satellites to realize accurate beam alignment, and supporting real-time updating of the global gateway station position table (including latitude, longitude, and altitude) to ensure the accuracy of link planning. Finally, the load monitoring unit generates instructions to interact with the ground gateway station according to the satellite load working state and the working parameters of other units to realize information alignment of the satellite-ground integration.

[0018] The routing switching unit mainly completes efficient information forwarding based on a dynamic routing table, supports inter-satellite and inter-satellite routing detection, periodically sends routing detection packets to monitor the inter-satellite link connectivity and transmission quality (such as error rate, delay, and other indicators) in real time, and further provides data support for the dual-dimension switching strategy through real-time monitoring of inter-satellite port traffic.

[0019] The inter-satellite processing unit mainly supports wireless signal transmission and reception and coding modulation of the inter-satellite link to realize mode conversion in dual-dimension switching. The circularly polarized phased array antenna (left-handed circular polarization LHCP) is adopted to support 50 ns level beam pointing fast switching and meet the link tracking requirements in the low-orbit constellation high-speed motion scenario.

[0020] The access network processing unit mainly completes baseband processing and wireless transmission of access signals and service data to adapt to diversified communication scenarios. Meanwhile, the access network processing unit supports three modes of antenna control, i.e., beam hopping, staring, and agile. The beam hopping polling is used for broadband user competition to improve multi-user access efficiency. The staring / agile mode is mainly used to provide directional high-speed transmission for key users or Internet services when the access beam traffic is low. The feeder processing unit mainly supports high-speed data transmission between the ground gateway station and the satellite, and provides physical layer support for the feeder link in mode switching. The right-hand circularly polarized (RHCP) antenna is used to form orthogonal isolation with the left-hand polarized inter-satellite link, to realize the same frequency parallel transmission of inter-satellite / earth-space link, and to avoid interference.

[0021] The technical solution breaks through the time delay and reliability bottleneck of traditional link switching through multi-unit cooperation and polarization isolation design, and realizes the double improvement of resource utilization rate and fault tolerance of low-orbit satellite communication network. The system monitors the inter-satellite link traffic load in real time through the load monitoring unit. When it is detected that the inter-satellite traffic is in the trough period, the data shunting and time division multiplexing strategy will be automatically triggered: first, the data of the A star and the adjacent star B4 interface is diverted to other adjacent stars for forwarding, and then the load monitoring unit calculates the beam angle, adjusts the inter-satellite phased array antenna originally pointing to the adjacent star B4 to the ground gateway station, and at the same time switches the inter-satellite processing unit to the feeder mode, finally redefines the original inter-satellite link as the feeder link, and realizes the elastic expansion of the satellite-earth communication capacity. When the inter-satellite link appears transmission failure or antenna alignment anomaly, the system will quickly start the fault response process: the load monitoring unit first determines whether there are visible gateway stations a and b4 for the A star and the adjacent star B4 respectively, and if so, it will issue instructions to the corresponding gateway stations to complete the synchronous ground frequency converter parameter configuration, transparent switching network port update and other work; the two satellites control the inter-satellite phased array antennas of the two stars to turn to the gateway stations a and b4 respectively, and build a "star-ground-star" relay channel through the ground transparent switching network, taking advantage of the high gain advantage (improving signal reception capability) and fixed position characteristics of the ground station large aperture antenna, to realize high-speed and stable transmission of cross-satellite data, greatly shorten the business interruption time, and in the process, there is no route change, small transmission time delay jitter and data packet disorder, which significantly improves the redundancy fault tolerance and resource utilization efficiency of the system. The ground transparent switching network is mainly composed of a microwave switching matrix and a ground optical fiber network.

[0022] The mode switching process of the inter-satellite / earth-space of the embodiment is as follows: Step 101: switching condition determination and pretreatment; when the inter-satellite antenna of the A star is visible to the gateway station and the stable link building time is greater than or equal to 5 minutes (which can be corrected in orbit), the traffic of the A star and the adjacent star B4 is less than or equal to 100MBps (which can be corrected in orbit), and the remaining ports have traffic sharing capability, the switching preparation process is entered.

[0023] Step 102: gateway station parameter preconfiguration; before switching, the load monitoring unit generates control instructions and sends them to the target gateway station through the feeder processing unit. The gateway station completes the pre-pointing adjustment of the ground antenna and the communication parameter configuration based on the instructions, to ensure the rapid establishment of the satellite-earth link.

[0024] Step 103: Network route pre-convergence; the routing exchange unit reports the "inter-satellite link B4 port is about to be disconnected" state to the network controller, and the controller completes route convergence and starts global route table diffusion mechanism to prepare for link switching at network layer.

[0025] Step 104: Dynamic adjustment of antenna pointing; after the interface data between satellite A and neighboring satellite B4 is completed, the load monitoring unit calculates the beam pointing angle according to the real-time orbit parameters of the satellite and the location of the gateway station, and turns the inter-satellite antenna from neighboring satellite B4 to the ground gateway station to complete the physical layer pointing reconfiguration.

[0026] Step 105: Feeding mode switching and link synchronization; during the process of pointing the inter-satellite antenna to the gateway station, the load monitoring unit switches the inter-satellite processing unit to the feeding mode. The inter-satellite processing unit initiates satellite-ground link synchronization through a pseudo-random sequence to establish a high-speed data transmission channel.

[0027] Step 106: Port function redefinition and route update; after the link synchronization is completed, the load monitoring unit sends instructions to the routing exchange unit to redefine the original inter-satellite interface between satellite A and neighboring satellite B4 as a feeding port. After the routing exchange unit completes the port function switching, it starts the route detection process, updates the global routing table and diffuses it to the entire network. At this point, the original inter-satellite processing unit is officially converted to a satellite-ground feeding link, realizing communication capacity improvement. To avoid sudden growth of local traffic, the system only retains basic user access functions, prioritizes internet user access success rate, and ensures access side service continuity.

[0028] Step 107: Intelligent decision-making for cross-satellite switching; when satellite A has new users accessing the network, the access network processing unit queries the coverage status of the remaining three neighboring satellites through the routing exchange unit: If the neighboring satellites can cover the new users, trigger the cross-satellite switching process and transfer the business to the neighboring satellites; If the neighboring satellites cannot cover, satellite A provides minimum traffic guarantee for users to maintain basic communication services.

[0029] Step 108, when satellite A is about to leave the gateway station, inform the ground network controller to complete convergence and route table diffusion; Step 109, after the route table diffusion is completed, the inter-satellite processing unit of satellite A is restored to realize inter-satellite communication.

[0030] The fault path switching implementation process of the embodiment is as follows: Step 201: Fault detection and triggering; when the inter-satellite link error rate between satellite A and neighboring satellite B4 continuously exceeds the threshold, and the rate adaptation mechanism cannot meet the communication requirements, the fault handling mode is automatically triggered.

[0031] Step 202: Gateway station visibility determination; the load monitoring unit calculates the gateway station visibility of the A star and the adjacent star B4 based on the real-time orbit parameters of the satellite and the gateway station parameter table: whether the two stars have available gateway stations respectively (A star and adjacent star B4).

[0032] Step 203: Ground gateway station parameter configuration; if the A star and the adjacent star B4 can see the gateway stations a and b4 respectively, the load monitoring unit generates control instructions according to the inter-satellite switching unit state and issues them to the corresponding gateway stations. After receiving the instructions, the gateway stations a and b4 complete the ground frequency converter parameter configuration, ground transparent switching network routing table update, modulation and demodulation parameter adaptation (such as coding mode and modulation order) simultaneously.

[0033] Step 204: Beam pointing cooperative adjustment; after the ground parameter configuration is completed, the load monitoring unit calculates the pointing angles of the two star antennas and issues instructions. Based on the unified satellite clock, the inter-satellite processing unit controls the antenna to perform beam hopping within the data protection time slot and accurately points to the corresponding gateway stations (A star→gateway station a, B4 star→gateway station b4).

[0034] Step 205: Ground-satellite relay link establishment; through the routing configuration of the ground switching matrix, the A star and the adjacent star B4 complete port connection through the "star-ground-star" relay channel. The system optimizes the data transmission path based on the known forwarding hop number and realizes zero interruption transmission of services in the inter-satellite link fault state.

[0035] Step 206: When either the A star or the adjacent star B4 is about to leave the gateway station, the A star and the adjacent star B4 inform the network controller of the gateway station of the disconnection message, and the network controller performs routing table diffusion after completing routing convergence; Step 207: After the diffusion is completed, the inter-satellite processing units of the A star and the adjacent star B4 are both restored for inter-satellite communication.

Claims

1. A two-dimensional switching system for low-orbit communication satellites, characterized in that: It includes load monitoring unit, routing switching unit, access network processing unit, feed processing unit and inter-satellite processing unit; The payload monitoring unit calculates the relative position vector between the satellite platform and the gateway based on ephemeris data and real-time orbital parameters, and predicts the stable link establishment time window. It also generates the three-dimensional pointing angle of the intersatellite antenna based on the orbital parameters of neighboring satellites to achieve beam alignment. A global gateway location table is built in, supporting real-time updates on-orbit. Based on the satellite payload's operating status and the operating parameters of the routing and switching unit, access network processing unit, feed processing unit, and intersatellite processing unit, the payload monitoring unit generates instructions to interact with the gateway, achieving integrated satellite-ground information alignment. The routing switching unit enables efficient information forwarding based on dynamic routing tables and supports inter-satellite and inter-satellite-ground routing detection. It also periodically sends routing detection packets to monitor inter-satellite link connectivity and transmission quality in real time. Furthermore, the routing switching unit monitors the traffic of each inter-satellite processing unit in real time, providing data support for dual-dimensional switching strategies. The intersatellite processing unit supports the wireless signal transmission and reception and coding modulation of the intersatellite link, realizing mode conversion in two-dimensional switching; The access network processing unit is responsible for baseband processing and wireless transmission and reception of access signals and service data. It also supports three antenna control modes: beam hopping, staring, and agile. Beam hopping polling is used to allow broadband users to compete for network access, improving multi-user access efficiency. Staring and agile modes are used to provide directional high-speed transmission for key users or Internet services when the incoming beam traffic is low. The feed processing unit supports high-speed data transmission and reception between the ground gateway and the satellite, and provides physical layer support for the feed link during mode switching.

2. A low-orbit communication satellite two-dimensional switching system according to claim 1, characterized in that: Based on the dynamic configuration capability of satellite payloads, the inter-satellite / satellite-to-ground mode switching and fault path switching are organically combined to build a three-dimensional switching network with multi-dimensional resource scheduling capabilities; the link status is perceived in real time through the payload monitoring unit, and mode conversion is automatically triggered in traffic fluctuation scenarios to release satellite-to-ground communication capacity. At the same time, when the link is abnormal, the transmission path adjustment is quickly initiated through beam hopping, forming a collaborative optimization system for capacity improvement and fault tolerance.

3. A low-orbit communication satellite two-dimensional switching system according to claim 2, characterized in that: The specific process of the inter-satellite / satellite-to-ground mode switching is as follows: Step 101: When the inter-satellite antenna of satellite A is visible to the gateway and the stabilization time exceeds the set minimum stabilization time, and the traffic between satellite A and neighboring satellite B4 is less than the set traffic threshold, and the original data can be forwarded through other neighboring satellites B1, B2, or B3, the pre-switching preparation process begins; Step 102: Before initiating the handover, the load monitoring unit generates a control instruction and sends it to the gateway via the feed processing unit. The gateway completes the configuration of the frequency converter, modem working parameters and ground antenna pre-pointing according to the received instruction. Step 103: Initiate a handover. The routing switching unit reports the port disconnection status to the network controller of the gateway through the power feeding processing unit. The network controller performs routing table diffusion after completing convergence. Step 104: After the interface data between satellite A and neighboring satellite B4 is directed, the payload monitoring unit calculates the beam angle based on the satellite's real-time parameters and the gateway's location, and completes the pointing adjustment. Adjusted from pointing to the neighboring satellite B4 to the ground signal gateway station; Step 105: When the antenna in the inter-satellite processing unit is pointing toward the gateway, the payload monitoring unit switches the inter-satellite processing unit to a feeding mode, and the inter-satellite processing unit establishes satellite-to-ground link synchronization using a pseudo-random sequence. Step 106: After link synchronization, the load monitoring unit generates an instruction to notify the routing switching unit to complete port switching, that is, to inform satellite A that the interface with neighboring satellite B4 will be used as the feed port. Then, the routing detection update and routing table propagation are completed. After all propagation is completed, the inter-satellite processing unit is used for satellite-to-ground power supply, and the satellite continues to retain user network access capabilities. Step 107: After a new user joins satellite A, the access network processing unit checks the coverage of neighboring satellites B1, B2, and B3 through the routing and switching unit. If the neighboring satellite can cover the new user, an inter-satellite handover is triggered; otherwise, satellite A provides the minimum service traffic to ensure the user can carry out services. Step 108, when A star is about to leave the gateway station, inform the ground network controller to complete the convergence after the routing table diffusion; Step 109: After the routing table is flooded, the inter-satellite processing unit of satellite A is restored to realize inter-satellite communication.

4. A low-orbit communication satellite dual-dimensional switching system according to claim 2, characterized in that: The specific process of failover is as follows: Step 201: When the bit error rate of the inter-satellite link between satellite A and neighboring satellite B4 continues to exceed the threshold, and the rate adaptation mechanism cannot meet the communication requirements; Step 202: The payload monitoring unit calculates the gateway visibility of satellite A and neighboring satellite B4 based on the satellite's real-time orbit parameters and the gateway parameter table. The determination principle is: whether there are available gateways for satellite A and neighboring satellite B4 respectively. Step 203: If satellite A and neighboring satellite B4 have visible gateway a and visible gateway b4 respectively, the payload monitoring unit generates a control instruction based on the status of the intersatellite switching unit and sends it to the corresponding gateway. After receiving the command, the visible signal gateway station a and the visible signal gateway station b4 synchronously complete the working parameter configuration, including the ground inverter parameter configuration, the ground transparent switching network port configuration update and the modulation and demodulation parameter adaptation; Step 204: After ground parameter configuration is complete, the payload monitoring units of satellite A and neighboring satellite B4 each calculate the antenna pointing angles and issue commands. The intersatellite processing unit, based on the satellite's unified clock, controls the antennas to perform beam hopping within the data protection time slot, pointing to their respective gateways. Satellite A points to visible gateway a, and neighboring satellite B4 points to visible gateway b4. Step 205: Satellite A and neighboring satellite B4 complete port connection via the satellite-ground-satellite relay channel through the routing configuration of the ground switching matrix. The data transmission path is optimized based on the known forwarding hop count to achieve zero service interruption transmission in the event of an inter-satellite link failure. Step 206: When either satellite A or neighboring satellite B4 is about to leave the gateway, satellite A and neighboring satellite B4 notify the network controller of the gateway of a link break message. The network controller then performs routing table diffusion after completing routing convergence. Step 207: After the diffusion is completed, the inter-satellite processing units of both satellite A and the neighboring satellite B4 are restored to achieve inter-satellite communication.

5. A low-orbit communication satellite two-dimensional switching system according to claim 4, characterized in that: The signals are forwarded to the ground gateway station through the inter-satellite antenna, and the ground transparent switching network is used to build a satellite-ground-satellite relay channel, where the ground transparent switching network realizes transparent signal forwarding and transmission.

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