A network protocol architecture method and system of a satellite optical wave / microwave composite networking system

Abstract

The application discloses a network protocol architecture method and system of a satellite optical wave / microwave composite networking system, belongs to the technical field of satellite communication networks, and solves the problems of an incomplete standard system, unreasonable protocol stack function division, poor dynamic topology adaptability of intersatellite links and insufficient modeling of physical layer link characteristics in the network protocol architecture of an existing satellite communication system. The application comprises a system standard architecture, a protocol stack architecture and an intersatellite link management architecture. The standard architecture is divided into five dimensions of system as a whole, networking protocol, security, operation and maintenance control, equipment and product. In the protocol stack architecture, the physical layer is not divided into data and control planes, control functions are completed by relying on data bearer type signaling, and the network layer is realized based on SDN technology to realize operation and management of the whole network. The intersatellite link management architecture constrains each satellite to establish at least two intersatellite links, and introduces a physical connectivity quantitative parameter to evaluate the topology connectivity capability. The application realizes unified architecture design of the optical wave / microwave composite networking system.

Description

Technical Field

[0001] This invention belongs to the field of satellite communication network technology, specifically relating to a network protocol architecture method and system for a satellite optical / microwave composite networking system. Background Technology

[0002] In the field of satellite communication networks, with the large-scale deployment of low Earth orbit (LEO) satellite constellations and the rapid growth in broadband service demands, building efficient, reliable, and scalable integrated space-ground communication networks has become a current research hotspot. Traditional satellite communication systems typically employ a single microwave or single optical wave transmission scheme, with relatively fixed network protocol architectures that struggle to simultaneously meet the comprehensive requirements of high bandwidth, low latency, flexible networking, and multi-service adaptation. In recent years, hybrid networking technologies integrating optical and microwave waves have attracted widespread attention. The core challenge lies in designing a unified network protocol architecture that is compatible with the characteristics of different physical transmission links and enables coordinated scheduling and management of inter-satellite and space-ground resources.

[0003] In existing technologies, the standardization of satellite communication systems often focuses on specific technical systems, lacking a systematic standard family plan guided by technical systems. Specifically, regarding overall system standards, existing solutions lack uniformity in defining network architecture, functional division, engineering interfaces, and capability assessment methods, resulting in poor interoperability across vendors and constellations. Regarding networking protocols, transmission and access systems for different transmission links (such as Ka-band microwave and laser links) have not yet been organically integrated, and key protocol processes such as integrated satellite-ground routing and switching, inter-satellite dynamic networking, and service access adaptation are redundant or missing. Furthermore, in terms of security protection and operation and maintenance management, existing network access control, security services, and integrated management mechanisms are mostly designed for terrestrial networks and are difficult to directly apply to satellite environments with highly dynamic topologies and long propagation delays.

[0004] At the protocol stack implementation level, most current satellite communication systems allocate independent signaling beam resources for control signaling, which consumes valuable spectrum and power resources, reducing the system's payload efficiency. Simultaneously, the functional division between the physical and data link layers in existing protocol stacks blurs the boundaries between the control and data planes, resulting in low efficiency in the coordinated processing of key processes such as radio resource scheduling, access control, and mobility management. Particularly at the network layer, the lack of effective integration with advanced technologies such as Software-Defined Networking (SDN) hinders the achievement of global network state awareness and dynamic optimization.

[0005] Furthermore, in terms of inter-satellite link (ISL) networking technology, laser links are considered the core physical links for building satellite optical networks due to their advantages such as high bandwidth and low interception probability. However, existing ISL topology generation and maintenance schemes are mostly based on static or semi-static configurations, failing to fully consider the dynamic changes in the availability of laser link terminals (such as PAT systems, i.e., acquisition, alignment, and tracking systems). When a laser link terminal of a node disconnects due to functional failure or resource occupation, existing topology reconstruction mechanisms often respond slowly, potentially causing network segmentation or decreased connectivity. Therefore, ensuring basic network connectivity in the event of node failure (e.g., each node maintaining at least two independent links) is a critical issue that urgently needs to be addressed.

[0006] Furthermore, accurate modeling of the spatial location, link distance (delay), and pointing angle (elevation / azimuth) of inter-satellite links is fundamental for routing protocol design, link budgeting, and antenna pointing control. Mathematical descriptions of the geometric relationships between existing constellation parameters (such as the N / P / F notation for the Walker constellation) and inter-satellite links are scattered across different literatures, lacking a systematic integration for network protocol design. In particular, the analytical expression for the time-varying link pointing angle is crucial for neighbor discovery and link switching decisions in dynamic networking protocols, yet current protocol architectures lack effective abstraction and utilization of such physical layer dynamic characteristics.

[0007] In summary, the existing network protocol architecture of satellite optical / microwave hybrid networking systems has significant shortcomings in terms of standard system completeness, rationality of protocol stack functional division, coordination between control and data planes, dynamic topology adaptability of inter-satellite links, and physical layer link characteristic modeling. Therefore, there is an urgent need to propose a novel network protocol architecture approach that can achieve unified and standardized design from the overall system, networking protocols, security operations and maintenance to equipment products, and realize the decoupling and coordination of the physical and network layers within the protocol stack. Furthermore, it should incorporate accurate mathematical models of inter-satellite links to support highly dynamic and highly reliable hybrid networking communication. Summary of the Invention

[0008] To address the problems of incomplete standardization, unreasonable functional division of protocol stacks, poor dynamic topology adaptability of inter-satellite links, and insufficient physical layer link characteristic modeling in the existing satellite communication system network protocol architecture, this invention provides a network protocol architecture method and system for a satellite optical / microwave composite networking system.

[0009] In a first aspect, the network protocol architecture method of a satellite optical / microwave composite networking system described in this invention includes three main parts: system standard architecture, protocol stack architecture, and inter-satellite link management architecture.

[0010] The system standard architecture is divided into five dimensions: overall system standards, networking protocol standards, security and confidentiality standards, operation and maintenance management standards, and equipment and product standards.

[0011] In the protocol stack architecture, the physical layer does not distinguish between the data plane and the control plane, and does not require the configuration of independent signaling beam resources. All control functions are completed by data-bearing signaling. The hierarchical control planes are divided as follows: the control planes of the physical layer and data link layer are responsible for managing user terminal access and handover; the network layer control plane is based on SDN software-defined networking technology to achieve full network operation management.

[0012] The inter-satellite link management architecture requires each satellite node to establish at least two inter-satellite links to ensure network connectivity redundancy; a physical connectivity quantification parameter is introduced to characterize the inter-satellite laser topology connectivity capability, which is the percentage of the number of currently enabled laser link terminals within the topology relative to the total number of all available laser link terminals on the satellite.

[0013] Preferably, the overall system standard includes standardized content on networking and functional architecture, engineering interfaces, application modes, system testing, and capability assessment methods; the networking protocol standard formulates transmission access systems, integrated satellite-ground routing and switching, inter-satellite networking, and service access adaptation specifications for multiple types of transmission links, and the transmission links include two types: Ka microwave links and laser inter-satellite links.

[0014] Preferably, the security and confidentiality standards cover three categories of specifications: transmission encryption, access authentication and authorization, and security of space-ground network interconnection; the operation and maintenance management standards include satellite telemetry and control, space-ground collaborative management and control, network-wide management, and telemetry, telemetry and control interaction interface standards; and the equipment and product standards specify the general technical requirements for handheld terminals, vehicle-mounted stations, portable stations, gateway stations, and supporting antennas.

[0015] Preferably, the layered structure of the communication protocol stack between the user terminal and the broadband service center is as follows: on the user terminal side, from bottom to top, the user link physical layer, space network link layer, network layer, transport layer, and application layer are deployed sequentially; on the satellite side, the user link physical layer, space network link layer, space network tunnel protocol layer, and power supply link physical layer are deployed sequentially; on the broadband service center side, from bottom to top, the user link physical layer, space network link layer, network layer, transport layer, and application layer are deployed sequentially; the user terminal and the satellite connect through the user link air interface, and the satellite and the broadband service center complete data interaction through the power supply link.

[0016] Preferably, the end-to-end communication protocol stack layered structure between user terminals is as follows: from bottom to top, the source user terminal side consists of the user link physical layer, space network link layer, network layer, transport layer, and application layer; the source satellite side includes the user link physical layer, space network link layer, and inter-satellite link physical layer; the relay satellite has inter-satellite link physical layers deployed on both sides, with a space network tunnel protocol layer in the middle; the destination satellite side sequentially deploys the inter-satellite link physical layer, space network link layer, and user link physical layer; from bottom to top, the destination user terminal side consists of the user link physical layer, space network link layer, network layer, transport layer, and application layer; adjacent network nodes communicate through the user link air interface or the inter-satellite link air interface.

[0017] Preferably, the core functions of the physical layer include physical frame assembly, signal modulation and demodulation, channel encoding and decoding, and physical layer link measurement; all operating parameters of the satellite-side physical layer are uniformly configured by the ground network controller; the core functions of the data link layer include radio resource scheduling, logical channel and transmission channel mapping, power and time-frequency joint control, service data multiplexing / demultiplexing, data segmentation, reordering, and concatenation processing; the terminal access control, radio connection management, and mobility management functions corresponding to the data link layer adopt a satellite-ground collaborative joint implementation mode.

[0018] Preferably, the maximum network degree of freedom of a single satellite node is determined by the number of laser link terminals carried by the satellite; when all laser link terminals of the satellite establish inter-satellite links and occupy them, the resulting inter-satellite network topology is a two-way Manhattan street network.

[0019] Preferably, the Walker constellation marking method is used to model the satellite distribution within the constellation, and the real-time spatial position of each satellite in the inertial coordinate system is solved based on the constellation's basic parameters; the phase offset of the nearest satellite in adjacent orbital planes is uniquely determined by the constellation phase factor.

[0020] Preferably, the real-time inter-satellite link distance between any two satellites is calculated from the difference magnitude of the position vectors of the two satellites' inertial coordinate systems; the elevation angle and azimuth angle required for the inter-satellite link transmitting optical terminal are obtained by jointly solving the orbital phase difference, orbital inclination angle, and distance between the ascending nodes of the orbital plane of the two communication satellites.

[0021] Secondly, the network protocol architecture system of the satellite optical / microwave composite networking system of the present invention includes:

[0022] The standard system management unit is used to define and maintain the specifications in five dimensions: overall system standards, networking protocol standards, security and confidentiality standards, operation and maintenance management standards, and equipment and product standards.

[0023] The protocol stack configuration unit is used to configure the protocol stack architecture. In the protocol stack architecture, the physical layer does not distinguish between the data plane and the control plane, and there is no need to configure independent signaling beam resources. All control functions are completed by data-bearing signaling. In the physical layer and data link layer, the control plane is used to complete the access and handover management of user terminals. In the network layer, the control plane realizes the operation management of the entire network based on software-defined networking technology.

[0024] The inter-satellite link management unit is used to manage the inter-satellite link architecture, constrain each satellite node to establish at least two inter-satellite links to ensure network connectivity redundancy, and calculate physical connectivity quantification parameters. The physical connectivity quantification parameters are the percentage of the number of currently enabled laser link terminals in the topology to the total number of all available laser link terminals on the satellite.

[0025] The beneficial effects of this invention are:

[0026] 1. This invention constructs a complete standard system from five dimensions: overall system, networking protocol, security and confidentiality, operation and maintenance management, equipment and products. It covers all aspects of satellite optical / microwave composite networking systems from top-level design to specific implementation. The dimensions are clearly hierarchical and closely connected, effectively solving the problem of poor interoperability between cross-vendor and cross-constellation systems in the prior art, and providing a unified technical basis for system engineering design, testing and verification and capability assessment.

[0027] 2. This invention does not allocate signaling beam resources separately at the physical layer. Control functions are implemented by signaling carried in data form, avoiding the additional occupation of spectrum and power resources by independent signaling beams and improving the system's payload efficiency. Simultaneously, this invention focuses on access and handover control at the data link and physical layers, and implements network operation management based on SDN technology at the network layer. The functional division between the control plane and data plane is clear and highly efficient, overcoming the shortcomings of high coupling between control and data processing flows and low scheduling efficiency in existing protocol stacks.

[0028] 3. This invention requires each satellite node to establish at least two inter-satellite links to ensure basic network connectivity. It also defines a physical connectivity parameter α to quantitatively evaluate topological connectivity, providing a clear basis for link configuration under dynamic topology conditions and effectively ensuring network robustness in the event of node or link failure. Furthermore, this invention establishes a complete mathematical model of the spatial location, link distance, and elevation / azimuth pointing angle of inter-satellite links, providing precise theoretical support for routing protocol design, link budget, and antenna pointing control. This facilitates accurate decision-making for neighbor discovery and link switching in dynamic networking protocols. Attached Figure Description

[0029] Figure 1 This is a standard architecture diagram of the satellite optical / microwave composite networking system provided in the embodiments of the present invention;

[0030] Figure 2 This is a schematic diagram of the communication protocol stack between the user terminal and the broadband service center provided in an embodiment of the present invention;

[0031] Figure 3 This is a schematic diagram of the communication protocol stack between user terminals provided in an embodiment of the present invention. Detailed Implementation

[0032] The technical solutions 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 some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0033] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0034] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but this is not intended to limit the scope of the invention.

[0035] To address the aforementioned problems in existing technologies, this invention provides a network protocol architecture method for a satellite optical / microwave hybrid networking system. In low-Earth orbit satellite constellation systems, the network protocol architecture is a core element determining system communication efficiency, resource utilization, and network reliability. In related technologies, the protocol architecture design of satellite communication systems typically faces three levels of technical contradictions.

[0036] The first contradiction lies between the completeness of the standards system and the complexity of system implementation. Existing satellite communication systems are mostly designed independently for specific missions or frequency bands, and their standards systems often only cover a single technology, lacking systematic standard planning for optical / microwave hybrid networking scenarios. At the overall system standards level, there is a lack of unified network architecture definitions and engineering interface specifications. At the network protocol level, there is a lack of transmission access mechanisms and integrated satellite-to-ground routing and switching mechanisms for different physical link characteristics, resulting in poor interoperability of multi-constellation and multi-vendor equipment and high system integration costs.

[0037] The second contradiction lies in the balance between efficiency and flexibility in the protocol stack architecture. Existing solutions typically allocate independent signaling beam resources for control signaling. While this simplifies control logic, it consumes valuable spectrum and power resources, reducing the system's payload efficiency. Simultaneously, the functional division between the control plane and data plane in traditional protocol stacks is blurred, especially at the physical and data link layers. The high coupling between control functions and data processing makes flexible radio resource scheduling and access control difficult. At the network layer, traditional distributed routing protocols struggle to adapt to the highly dynamic changes in LEO constellation topologies, exhibiting slow routing convergence and insufficient global optimization capabilities.

[0038] The third contradiction lies in the balance between the reliability and dynamic adaptability of inter-satellite link networks. While laser links offer advantages such as high bandwidth and low probability of interception, their link terminals are susceptible to dynamic failures in acquisition, alignment, and tracking functions. Existing topology generation and maintenance schemes are mostly static or semi-static configurations. When a laser link terminal at a node disconnects due to functional failure or resource occupation, the topology reconstruction mechanism lags behind, potentially causing network segmentation. Furthermore, precise mathematical models of the spatial location, link distance, and pointing angle of inter-satellite links are fundamental to routing protocol design and link budgets. However, existing protocol architectures lack effective abstractions of these dynamic physical layer characteristics, leading to a disconnect between routing decisions and physical link states.

[0039] To address the aforementioned problems, this invention employs a systematic design from three levels: standard architecture, protocol stack architecture, and inter-satellite link management architecture. The specific embodiments of this invention are described in detail below with reference to the accompanying drawings.

[0040] This invention provides a network protocol architecture method for a satellite optical / microwave composite networking system, comprising three main parts: system standard architecture, protocol stack architecture, and inter-satellite link management architecture.

[0041] The system standard architecture is divided into five dimensions: overall system standards, networking protocol standards, security and confidentiality standards, operation and maintenance management standards, and equipment and product standards.

[0042] In the protocol stack architecture, the physical layer does not distinguish between the data plane and the control plane, and does not require the configuration of independent signaling beam resources. All control functions are completed by data-bearing signaling. The hierarchical control planes are divided as follows: the control planes of the physical layer and data link layer are responsible for managing user terminal access and handover; the network layer control plane is based on SDN software-defined networking technology to achieve full network operation management.

[0043] The inter-satellite link management architecture requires each satellite node to establish at least two inter-satellite links to ensure network connectivity redundancy; a physical connectivity quantification parameter is introduced to characterize the inter-satellite laser topology connectivity capability, which is the percentage of the number of currently enabled laser link terminals within the topology relative to the total number of all available laser link terminals on the satellite.

[0044] Specifically, at the system standard architecture level, this invention divides it into five dimensions: overall system standards, networking protocol standards, security and confidentiality standards, operation and maintenance management standards, and equipment and product standards. The overall system standards standardize the networking architecture, functional architecture, engineering interfaces, application modes, system testing, and capability assessment methods at the top-level system design, ensuring a unified design language and technical baseline at the architectural level. The networking protocol standards standardize transmission and access mechanisms for different transmission links, integrated satellite-to-ground routing and switching, inter-satellite networking, and service access adaptation, providing protocol support for the collaborative operation of optical and microwave links. The security and confidentiality standards and operation and maintenance management standards respectively address network access control, security services, and network integration management issues. The equipment and product standards standardize the technical requirements for various terminals and ground stations. Through standardization across these five dimensions, the system achieves unified technical systems and scalability at the top-level architecture level.

[0045] At the protocol stack architecture level, this invention adopts a design scheme in which the physical layer does not distinguish between the data plane and the control plane, eliminating the need for independent signaling beam resources. All control functions are completed through data-bearing signaling. This design avoids the additional occupation of spectrum and power resources by independent signaling beams in traditional schemes. Based on this, this invention employs a layered control plane division of labor mechanism: at the physical and data link layers, the control plane is responsible for managing user terminal access and handover; at the network layer, the control plane implements network-wide operation management based on software-defined networking (SDN) technology. The introduction of SDN technology enables the control plane to centrally manage the entire network state, distributing flow tables to the data plane through the southbound interface, achieving centralized calculation and dynamic adjustment of routing policies, thereby overcoming the problems of slow convergence and susceptibility to local optima in the highly dynamic topology of low-Earth orbit constellations in traditional distributed routing protocols.

[0046] At the inter-satellite link management architecture level, this invention mandates that each satellite node establish at least two inter-satellite links to ensure network connectivity redundancy. This design ensures that when a link of a node is lost due to terminal failure or obstruction, the node can still maintain connectivity with the network through other links, avoiding network segmentation. To quantitatively evaluate the topological connectivity of inter-satellite links, this invention introduces a physical connectivity quantification parameter, defined as the percentage of currently active laser link terminals within the topology relative to the total number of available laser link terminals on the satellite. This parameter directly reflects the physical connectivity of the network topology, providing a quantitative basis for link configuration and reconfiguration under dynamic topology conditions.

[0047] Furthermore, the overall system standard includes standardized content on networking and functional architecture, engineering interfaces, application modes, system testing, and capability assessment methods; the networking protocol standard sets out transmission access systems, integrated satellite-ground routing and switching, inter-satellite networking, and service access adaptation specifications for multiple types of transmission links, and the transmission links include two types: Ka microwave links and laser inter-satellite links.

[0048] Specifically, the overall system standard serves as the top-level foundation of the standard architecture. The networking and functional architecture defines the overall topology of the integrated satellite optical network and microwave network, clarifying the functional positioning and responsibilities of various node types, including satellite nodes, ground gateway stations, network controllers, and user terminals, providing unified architectural constraints for subsequent protocol design and equipment development. The engineering interface standard specifies the physical form, electrical parameters, protocol stack adaptation layer format, and signaling interaction process of interfaces between satellite-to-ground links, inter-satellite links, and between satellite-to-ground and terrestrial networks, ensuring interoperability at the interface level for equipment from different manufacturers. The application mode standard defines the system's operating modes in different business scenarios such as broadband access, relay transmission, emergency communication, and IoT data acquisition. Each mode corresponds to a set of preset system parameters, resource allocation strategies, and quality of service assurance strategies, enabling the system to quickly switch to the optimal operating state according to task requirements. The system testing standard covers end-to-end latency testing, throughput testing, link availability testing, fault recovery testing, and long-term stability testing, providing unified testing methods and judgment criteria for system delivery acceptance and on-orbit operation and maintenance. The capability assessment methodology standard defines quantitative assessment indicators and assessment processes for system capabilities from multiple dimensions such as coverage, communication capacity, transmission latency, availability, and anti-interference capability, providing data support for the continuous optimization and upgrading of the system.

[0049] Networking protocol standards serve as an intermediate layer in the standard architecture, connecting the overall system standard with specific protocol implementations. The transmission and access system specifications define suitable physical layer parameters for Ka-band microwave links and laser inter-satellite links, including carrier frequency, modulation scheme, coding scheme, frame structure, and multiple access method. This enables differentiated transmission capabilities at the physical layer for the two types of links, while allowing unified service data transmission at the link layer. The integrated satellite-to-ground routing and switching specifications define the routing information exchange mechanism and routing table maintenance process between on-board and ground routes, enabling seamless forwarding of data packets between inter-satellite and ground links. This solves the problems of fragmented satellite-to-ground routing and suboptimal path selection in traditional satellite systems. The inter-satellite networking specifications define the entire lifecycle management process for inter-satellite links, including neighbor discovery, link establishment, link maintenance, link quality monitoring, and link switching, ensuring that the inter-satellite topology remains connected even under high-speed satellite motion. The service access adaptation specification defines the protocol adaptation and format conversion rules for different types of service data before entering the space network, including the encapsulation format of IP packets, service quality label mapping, and traffic shaping strategies, to ensure that diverse services such as voice, video, and data can be efficiently carried under a unified network protocol framework.

[0050] In complex networking scenarios with multiple transmission links, Ka-band microwave links and laser inter-satellite links have complementary transmission characteristics. They require coordinated scheduling at the protocol level to leverage the overall advantages of the complex network. This invention defines suitable physical layer parameters, link layer frame formats, and access procedures for the two types of links through transmission and access system specifications in networking protocol standards. It achieves cross-link and inter-satellite routing information exchange and forwarding decisions through integrated satellite-ground routing and switching specifications. Furthermore, it enables collaborative networking and service carrying across multiple links through inter-satellite networking and service access adaptation specifications. The establishment of this standard system solves the problems of poor interoperability and protocol redundancy between devices with different technical systems in complex networking scenarios, providing a standard guarantee for achieving optical and microwave collaboration at the system architecture level.

[0051] In a preferred embodiment, for the transmission and access system of Ka microwave links, the physical layer adopts a multi-carrier modulation method, including orthogonal frequency division multiplexing (OFDM) technology, with a subcarrier spacing of 15 kHz or 30 kHz. The modulation and coding scheme is dynamically configured based on the link budget results. The modulation and coding schemes include orthogonal phase shift keying (PPS), hexadecimal orthogonal amplitude modulation (HAM), and 64-ary orthogonal amplitude modulation (SAM). Low-density parity-check (LDPC) coding is used, and the code rate can be configured between 1 / 3 and 8 / 9. For the transmission and access system of laser inter-satellite links, the physical layer adopts pulse position modulation (PPM) or binary phase shift keying (BPS). The PPM order is 4, 8, or 16. The transmitted optical power and coding code rate are dynamically adjusted based on the link distance and atmospheric turbulence intensity. The transmitted optical power adjustment range is 10 milliwatts to 10 watts. The coding uses a concatenated code of Reed-Solomon codes or convolutional codes and LDPC codes. The integrated satellite-ground routing and switching specification adopts a satellite-extended version of the Border Gateway Protocol, supporting flooding of inter-satellite link state information and distributed computation of routing tables. The route update cycle is 1 to 10 seconds to adapt to the rapid changes in low-Earth orbit constellation topology. The inter-satellite networking specification defines the complete signaling process for establishing, maintaining, and tearing down inter-satellite links. This includes: a neighbor discovery phase identifying neighboring satellites within line of sight via broadcast beacon frames; a link initialization phase establishing physical connections and logical associations through a three-way handshake; a heartbeat maintenance phase periodically exchanging link state information at a frequency of 1 to 10 Hz; and a link switching phase triggering the rapid establishment of backup links based on link quality measurement results. The total latency of the entire switching process is controlled within 100 milliseconds. The service access adaptation specification defines four service quality levels for different types of services: real-time session, real-time streaming media, interactive, and background. Each service type corresponds to an independent queue management and scheduling strategy to ensure that high-priority services receive priority forwarding when links are congested.

[0052] Furthermore, the security and confidentiality standards cover three categories of specifications: transmission encryption, access authentication and authorization, and security of space-ground network interconnection; the operation and maintenance management standards include satellite telemetry and control, space-ground collaborative management and control, network-wide management, and telemetry, telemetry and control interaction interface standards; and the equipment and product standards specify the general technical requirements for handheld terminals, vehicle-mounted stations, portable stations, gateway stations, and supporting antennas.

[0053] Specifically, the establishment of the security and confidentiality standards system aims to address the inherent security vulnerabilities of satellite communication networks in open space transmission environments. Satellite communication links are characterized by wide coverage and open signal propagation, exposing both satellite-to-ground and inter-satellite links to potential interception, interference, and tampering threats. Transmission encryption specifications ensure the confidentiality and integrity of data transmission at both the physical layer and link layer encryption levels. Physical layer encryption uses spread spectrum technology, frequency hopping technology, or physical layer secure coding methods to make signals difficult to demodulate and identify under non-cooperative reception conditions. Link layer encryption uses symmetric encryption algorithms to encrypt and protect the payload of data frames, and the key management mechanism supports periodic key updates and key revocation in emergencies, ensuring that even if a single frame of data is intercepted, valid information cannot be decrypted. Access authentication and authorization specifications address the issue of trustworthy user terminal identities. In satellite networks, due to limited onboard processing resources, the complex authentication processes based on multiple interactions in traditional terrestrial networks are difficult to directly apply. This invention employs a lightweight ternary peer-to-peer authentication mechanism, where authentication is collaboratively completed by the user terminal, satellite, and ground authentication server. Before joining the network, the user terminal must complete two-way identity verification with both the satellite and ground authentication servers. After successful verification, the ground authentication server generates a temporary session key and distributes it to the satellite and the terminal for subsequent communication encryption protection. The space-ground network interconnection security specification addresses the security boundary issue when satellite networks interconnect with the terrestrial internet and terrestrial telecommunications networks. When a satellite network connects to the internet as an extension of a terrestrial network, a security gateway needs to be deployed at the interconnection node to implement functions such as protocol filtering, intrusion detection, security auditing, and network address translation. This prevents attack traffic from the terrestrial network from penetrating the satellite network through the interconnection node, while also preventing abnormal traffic from the satellite network from impacting the terrestrial network.

[0054] Operation and maintenance management standards are crucial for ensuring the long-term stable operation of the system. Satellite telemetry and control specifications cover telemetry data acquisition, status monitoring, orbit maintenance, and attitude control for the satellite platform and payloads. Telemetry data includes satellite platform status parameters such as bus voltage, bus current, onboard temperature, and propellant remaining quantity, as well as payload status parameters such as transmitter power, receiver sensitivity, and laser terminal pointing accuracy. The telemetry and control system uses telemetry data to determine whether the satellite is in normal working condition and triggers corresponding handling procedures when anomalies occur. The satellite-ground collaborative management and control specifications define the collaborative mode and authority division between onboard autonomous management and the ground control center. Under normal conditions, the satellite operates independently according to a preset autonomous management and control strategy, including autonomous orbit maintenance, autonomous attitude stabilization, and autonomous payload management. When the ground control center needs to perform global operations, such as constellation configuration adjustments, inter-satellite link topology replanning, and on-orbit software upgrades, it takes over some or all of the satellite's management authority through uplink commands. This collaborative mode balances the real-time nature of onboard autonomous operation with the global scope of centralized ground control. The network management specifications cover four aspects: configuration management, performance management, fault management, and security management. Configuration management includes initial configuration of network nodes, adjustment of operating parameters, and configuration version management. Performance management includes link quality monitoring, traffic statistics, and service quality indicator monitoring. Fault management includes fault detection, fault location, fault isolation, and fault recovery. Security management is aligned with security and confidentiality standards, responsible for security policy formulation, security event monitoring, and security audit log management. The telemetry, tracking, and command (TT&C) interface standard specifies the data exchange format and communication protocol between the TT&C system and the operations control system. The TT&C system is responsible for satellite platform health management, while the operations control system is responsible for business data scheduling and network resource management. The two systems need to exchange data such as satellite availability status, beam pointing information, and resource occupancy. This invention uses a unified extensible markup language format to define the interface data model, ensuring interface compatibility between TT&C systems and operations control systems from different vendors.

[0055] The establishment of equipment and product standards ensures interoperability between different types of terminal equipment in terms of interfaces, protocols, and performance. Handheld terminals are suitable for individual soldier carrying and emergency communication scenarios, and their technical requirements include transmit power, receive sensitivity, antenna gain, battery life, and protection level. Vehicle-mounted stations are suitable for vehicle platform mounting, and their technical requirements, in addition to RF performance, include vibration adaptability, temperature adaptability, and electromagnetic compatibility. Portable stations are suitable for rapid deployment scenarios, and their technical requirements emphasize lightweight design, rapid deployment, and automatic satellite alignment capabilities. Gateway stations, as interconnection nodes between satellite networks and terrestrial networks, have technical requirements including the gain and pointing accuracy of large-aperture antennas, the output capability of high-power amplifiers, the processing power of modems, and the throughput and concurrent connection count of security gateways. Supporting antennas cover a complete series from small-aperture antennas for handheld terminals to large-aperture parabolic antennas for gateway stations, with clearly defined technical specifications for the gain, beamwidth, polarization, and tracking accuracy of each antenna.

[0056] In a preferred embodiment, for transmission encryption, the inter-satellite link employs a symmetric encryption algorithm based on quantum key distribution. Quantum key distribution achieves real-time generation and distribution of key materials through the transmission of entangled photon pairs on the inter-satellite laser link. The key update cycle is 60 to 300 seconds, ensuring that even if the key is intercepted, its effective usage window is extremely short, and the risk of information leakage is controllable. The satellite-to-ground link adopts a certificate-based asymmetric encryption system. The public key infrastructure is uniformly managed by the ground authentication server. The user terminal and the satellite each hold a digital certificate issued by the authentication center for identity verification and session key negotiation before communication. The session key negotiation adopts an elliptic curve key exchange algorithm with a key length of 256 bits. The three-element peer-to-peer authentication process defined in the access authentication and authorization specification specifically includes: the user terminal sends an access request to the satellite, the satellite forwards the request to the ground authentication server, the authentication server verifies the validity of the terminal certificate and generates an authentication token and a temporary session key, and sends both to the terminal via the satellite. The terminal uses the authentication token to complete the subsequent service connection establishment. The total interaction latency of this process is controlled within 500 milliseconds. The space-ground network interconnection security specification requires security gateways to be deployed at the interconnection nodes between the satellite network and the terrestrial internet. These gateways must possess deep packet inspection capabilities to identify and filter attack traffic based on satellite protocols, and support virtual private network tunneling protocols to ensure encrypted tunnel transmission of cross-domain traffic between the satellite and terrestrial networks, preventing plaintext exposure. Regarding operation and maintenance management, the space-ground collaborative management specification's permission allocation strategy is as follows: orbit maintenance, attitude control, and payload health management under normal conditions are autonomously performed by the satellite. When a satellite's attitude deviation exceeds a preset threshold (e.g., pitch angle deviation greater than 0.1 degrees), or the temperature of a critical onboard device exceeds its operating range, the satellite automatically reports the abnormal event to the ground control center and awaits ground instructions. The configuration management of the entire network adopts an automated configuration distribution mechanism based on a network configuration protocol. The ground network controller uses this protocol to batch-distribute configuration parameters to all satellite nodes. Configuration distribution employs a phased, step-by-step strategy, selecting no more than three satellites for initial verification before expanding to the entire constellation, thus reducing the risk of network-wide failure due to configuration errors. The interface data model of the measurement, control, and operation (TCO) interaction interface standard is defined using Extensible Markup Language (XML). Each interface message includes a message header, message body, and a checksum field. The message header records the message type, sender identifier, receiver identifier, and timestamp. The message body carries the specific measurement and control parameters or OCO parameters. The checksum field uses cyclic redundancy check to ensure the correctness of data transmission. In equipment and product standards, the handheld terminal's transmit power is 0.5 watts to 2 watts, receive sensitivity is better than -100 dB / mW, antenna gain is 2 dB to 5 dB, battery life is no less than 8 hours, and protection level reaches IP67.The vehicle-mounted station has a transmit power of 5 watts to 20 watts, an antenna aperture of 0.3 meters to 0.6 meters, vibration adaptability that meets the vibration spectrum requirements of the vehicle-mounted platform, and a temperature adaptability range of -40 degrees Celsius to 60 degrees Celsius. The portable station's deployment time is no more than 3 minutes, and its automatic satellite alignment accuracy is better than 0.2 degrees. The gateway station has a large-aperture antenna aperture of 3.7 meters to 7.3 meters, a high-power amplifier output power of 100 watts to 500 watts, a security gateway throughput of no less than 10 gigabits per second, and a concurrent connection count of no less than 1 million.

[0057] Furthermore, the layered structure of the communication protocol stack between the user terminal and the broadband service center is as follows: on the user terminal side, from bottom to top, the user link physical layer, space network link layer, network layer, transport layer, and application layer are deployed sequentially; on the satellite side, the user link physical layer, space network link layer, space network tunnel protocol layer, and feeder link physical layer are deployed sequentially; on the broadband service center side, from bottom to top, the user link physical layer, space network link layer, network layer, transport layer, and application layer are deployed sequentially; the user terminal and the satellite connect through the user link air interface, and the satellite and the broadband service center complete data interaction through the feeder link.

[0058] Specifically, the protocol stack structure is designed based on the overall principle of separating the control plane and the data plane. On the user terminal side, the user link physical layer is responsible for modulation and demodulation of Ka-band signals, channel encoding and decoding, and physical layer measurements. The space network link layer is responsible for data link layer functions such as radio resource scheduling, logical channel and transport channel mapping, power control, and data multiplexing and demultiplexing. The network layer and above are responsible for IP packet routing and forwarding, and end-to-end transmission control. On the satellite side, the user link physical layer receives and demodulates uplink signals from the user terminal. The space network link layer handles user terminal access control, radio connection management, and mobility management. The space network tunneling protocol layer encapsulates user data into an inter-satellite link transmission format. The feeder link physical layer is responsible for data downlink to the terrestrial broadband service center. The protocol stack structure on the broadband service center side corresponds to that on the user terminal side, completing the reception, decapsulation, and forwarding of feeder link data to the terrestrial network.

[0059] In the communication scenario between user terminals and broadband service centers, user data is transmitted from the terminal, uplinked to the satellite via the user link air interface, converted from the user link protocol to the feeder link protocol on the satellite side, and then downlinked to the ground broadband service center via the feeder link, ultimately entering the terrestrial internet. During this process, the space network link layer establishes a one-to-one logical connection between the user terminal and the satellite side. The network controller uniformly configures physical layer parameters, including transmit power, modulation and coding scheme, and time-frequency resource block location. Since the physical layer does not distinguish between the data plane and the control plane, control signaling is carried on the user link physical layer in data frame format, sharing the same physical channel with user service data, eliminating the need for independent allocation of signaling beam resources. This design simplifies satellite payload configuration while improving spectrum utilization efficiency.

[0060] In a preferred embodiment, the user link air interface employs frequency division duplexing (FDM) or time division duplexing at the physical layer, with the specific choice depending on the duplexing capability of the user terminal and the service scenario. For broadband service center scenarios, the user terminal uplink uses a designated uplink frequency band and time slot, while the satellite downlink uses a designated downlink frequency band and time slot. The space network tunneling protocol layer employs IP tunneling encapsulation technology to encapsulate the user terminal's raw IP data packets into data frames with inter-satellite routing tags for inter-satellite forwarding within the satellite network. The feeder link physical layer uses a large-aperture antenna in the Q-band or V-band to establish a high-speed data channel with the ground gateway station. The data transmission rate of the feeder link is higher than that of the user link to support the aggregation and transmission of multi-user data.

[0061] Furthermore, the end-to-end communication protocol stack layered structure between user terminals is as follows: from bottom to top, the source user terminal side consists of the user link physical layer, space network link layer, network layer, transport layer, and application layer; the source satellite side includes the user link physical layer, space network link layer, and inter-satellite link physical layer; the relay satellite has inter-satellite link physical layers deployed on both sides, with a space network tunnel protocol layer in the middle; the destination satellite side sequentially deploys the inter-satellite link physical layer, space network link layer, and user link physical layer; from bottom to top, the destination user terminal side consists of the user link physical layer, space network link layer, network layer, transport layer, and application layer; adjacent network nodes communicate through the user link air interface or the inter-satellite link air interface.

[0062] Specifically, the communication scenario between user terminals involves two levels of air interfaces: user link and inter-satellite link. At the source user terminal, user data is processed sequentially through the application layer, transport layer, network layer, space network link layer, and user link physical layer before being uplinked to the source satellite via the user link air interface. After demodulation at the user link physical layer, the source satellite extracts the user data at the space network link layer, delivers it to the inter-satellite link physical layer for modulation, and forwards it to the relay satellite via the inter-satellite link air interface. Upon receiving the data at the inter-satellite link physical layer, the relay satellite transparently forwards it through the space network tunnel protocol layer, without involving decapsulation or recapsulation of user data, thus reducing onboard processing latency and complexity. After completing the protocol conversion for inter-satellite link reception and user link transmission, the destination satellite downlinks the data to the destination user terminal via the user link air interface. The destination terminal then unpacks the data according to the reverse protocol stack to obtain the original user data.

[0063] In end-to-end communication scenarios, the space network tunneling protocol layer establishes an end-to-end logical tunnel between the source and destination satellites, carrying user data in a tunneled manner during inter-satellite link transmission. The establishment and maintenance of this tunnel are centrally managed by the software-defined network controller at the network layer. Based on ephemeris information and network topology status, the controller calculates the optimal inter-satellite path for each pair of communication terminals and distributes the path information to each satellite node in the form of a flow table. When a satellite node experiences topology changes due to orbital motion or link failure, the controller recalculates the path and updates the flow table, achieving dynamic route adjustment. The introduction of software-defined networking technology enables the network layer control plane to perform real-time perception and centralized decision-making regarding the status of all inter-satellite links in the network, avoiding the routing oscillations and convergence delays that traditional distributed routing protocols suffer from during dynamic topology changes.

[0064] In a preferred embodiment, the inter-satellite link air interface employs a laser communication system at the physical layer, operating in the 1550 nm band. The inter-satellite link physical layer includes laser signal transmission and reception, acquisition, alignment, and tracking functions, modulation and demodulation, and channel coding. The operating parameters of the inter-satellite link physical layer, including transmitted optical power, modulation format, and coding rate, are uniformly configured by the network controller based on link distance and channel conditions. The data link layer of the inter-satellite link air interface adopts a connection-oriented acknowledgment and retransmission mechanism to accommodate the potential for momentary interruptions in laser links due to atmospheric conditions and pointing accuracy. The relay satellite's space network tunnel protocol layer does not parse the content of user data; it only forwards data frames from the ingress port to the egress port based on tunnel tags, achieving lightweight onboard processing.

[0065] Furthermore, the core functions of the physical layer include physical frame assembly, signal modulation and demodulation, channel encoding and decoding, and physical layer link measurement; all operating parameters of the satellite-side physical layer are uniformly configured by the ground network controller; the core functions of the data link layer include radio resource scheduling, logical channel and transmission channel mapping, power and time-frequency joint control, service data multiplexing / demultiplexing, data segmentation, reordering, and concatenation processing; the terminal access control, radio connection management, and mobility management functions corresponding to the data link layer adopt a satellite-ground collaborative joint implementation mode.

[0066] Specifically, the functional division and collaborative relationship between the physical layer and the data link layer are the core of the protocol stack architecture. The physical layer completes the physical transmission of signals, and its parameter configuration directly affects link quality and spectral efficiency. This invention entrusts all operational parameters of the satellite-side physical layer to the ground network controller for unified configuration, enabling the adjustment of physical layer parameters to be optimized based on the global network status. The network controller, through a software-defined network control plane, dynamically adjusts the physical layer parameters of each satellite node and user terminal, including transmit power, modulation and coding scheme, and time-frequency resource allocation, based on the service requirements of user terminals, channel quality measurement results, and system resource occupancy, to achieve a balance between link quality assurance and maximizing system capacity.

[0067] The data link layer, above the physical layer, provides terminal-oriented access control and connection management functions. This invention adopts a satellite-ground collaborative implementation model: the onboard data link layer is responsible for real-time operations such as wireless resource scheduling, power control, and data multiplexing / demultiplexing, ensuring low latency and high reliability. The ground network controller is responsible for global access control decisions, wireless connection lifecycle management, and mobility management, ensuring connection continuity and quality of service when terminals switch between different satellite beams. This division of labor leverages both the low latency advantage of onboard processing and the global decision-making capabilities of the ground controller, overcoming the limitations of purely onboard processing schemes (limited decision-making capabilities) and purely ground processing schemes (excessively high latency).

[0068] In a preferred embodiment, the terminal access control process includes three stages: random access request, access authorization, and resource allocation. The user terminal sends an access preamble sequence through the random access channel of the user link physical layer. After detecting the preamble sequence, the satellite reports the access request to the network controller. The network controller makes an access decision based on the current resource occupancy and the terminal's service level, and notifies the terminal of the decision result and allocated physical resources via the downlink. The terminal then initiates a service connection establishment process on the designated resources. The mobility management process includes three stages: adjacent beam measurement reporting, handover decision, and handover execution. The handover decision is made by the ground network controller based on the terminal's measurement report and the load status of multiple satellites. The power and time-frequency joint control function is adjusted in real time by the satellite-side data link layer based on channel quality indications and interference measurement results, with an adjustment period on the order of milliseconds to adapt to rapid channel changes.

[0069] Furthermore, the maximum network freedom of a single satellite node is determined by the number of laser link terminals carried by the satellite; when all laser link terminals of the satellite establish and occupy inter-satellite links, the resulting inter-satellite network topology is a two-way Manhattan street network.

[0070] Specifically, one of the core constraints of the inter-satellite link management architecture is that each satellite node must establish at least two inter-satellite links to ensure network connectivity redundancy. The theoretical basis for this constraint lies in the concept of node connectivity in graph theory—when each node in the network has at least 2 degrees of freedom, the failure of a single link will not lead to network splitting, and there is at least one alternative path between any two nodes. The maximum degree of freedom of a satellite node is limited by the number of laser link terminals it carries. Each laser link terminal can only establish one inter-satellite link with one adjacent node at a time; therefore, the maximum degree of freedom of a node equals the number of terminals. When all laser link terminals are occupied, inter-satellite link resources are fully utilized, and the system has maximum connectivity redundancy and routing flexibility. If each satellite carries four laser link terminals and all establish inter-satellite links, and each node establishes one link with each of its four adjacent nodes in the four directions (front, back, left, and right), the resulting network topology is a bidirectional Manhattan street network.

[0071] To quantitatively assess the physical connectivity of inter-satellite link topologies, this invention introduces a physical connectivity quantification parameter. This parameter is defined as the ratio of the number of all inter-satellite links in the generated network topology to the total number of inter-satellite links in the network topology when each satellite node has its maximum degree of freedom. Physically, this parameter represents the percentage of simultaneously occupied laser link terminals out of all available laser link terminals in the network topology, and its value range is... The closer the value is to 1, the higher the topological connectivity. The specific formula is as follows:

[0072] (1)

[0073] In the formula, This represents the number of ISLs in the current network topology. This represents the maximum degree of freedom of the network nodes. It represents the number of laser link terminals carried by each satellite. The coefficient 2 in the numerator stems from the fact that each inter-satellite link occupies two laser link terminals, one for the transmitting end and one for the receiving end. The denominator... This represents the total number of terminals occupied, corresponding to the maximum number of inter-satellite links that can be established in the network when all laser link terminals of all satellites are occupied. This parameter provides network administrators and automated operation and maintenance systems with an intuitive quantitative indicator of connectivity, used to trigger link reconfiguration or topology optimization processes. When When the value is lower than the preset threshold, it indicates that the network topology connectivity has dropped to a dangerous level, and the system should automatically initiate the link reconstruction process.

[0074] In a preferred embodiment, when a satellite's laser link terminal experiences a malfunction in its acquisition, alignment, or tracking functions, resulting in a link disconnection, the satellite node needs to attempt to establish a backup link with other satellites within its line of sight. The selection rule for the backup link is: prioritize neighboring satellites with the fewest currently established links to ensure the link load on the network topology is as balanced as possible. If enough backup links cannot be established within a preset time period to meet the minimum requirement of two links, the satellite node reports a connectivity degradation event to the network controller, which then coordinates with neighboring satellites to adjust beam pointing or reallocate link resources. After each round of topology adjustment, the network controller recalculates the current topology. The value is compared with the threshold, if If the value recovers to above the threshold, the normal link maintenance procedure continues; if If the value remains below the threshold, a larger-scale topology replanning process is initiated. Assuming a constellation consists of 100 satellites, each carrying 4 laser link terminals, then... The value equals 4, meaning the total number of inter-satellite links is 200 when all terminals are occupied. If the number of inter-satellite links actually established is 150, then... This indicates that 75% of the laser link terminals are currently occupied, and there is a certain degree of connectivity redundancy loss in the network. The system should assess whether it is necessary to initiate link reconstruction.

[0075] Furthermore, the Walker constellation labeling method is used to model the satellite distribution within the constellation, and the real-time spatial position of each satellite in the inertial coordinate system is solved based on the constellation's basic parameters; the phase offset of the nearest satellite in adjacent orbital planes is uniquely determined by the constellation phase factor.

[0076] Specifically, the Walker constellation marking method uses The representation of , where This indicates the total number of satellites in the constellation. This indicates the total number of orbits contained within a constellation. The phase factors representing constellations, This indicates the number of satellites in each orbit, satisfying the following conditions: The phase offset between the two nearest satellites in adjacent orbits is determined by... Decide, The range of values ​​is Integers between 1 and 2. This notation method can uniquely determine the spatial position of each satellite in the constellation at any given time, and is the basis for inter-satellite link distances, pointing angles, and topology planning.

[0077] Based on spatial geometric relationships, the first constellation... The first track The position vector of a satellite in an inertial coordinate system can be expressed as:

[0078] (2)

[0079] (3)

[0080] (4)

[0081] In the formula, The value is , indicating the sequence number of the orbital plane. The value is , indicating the first The serial number of the satellite within the orbit. It indicates the distance between the satellite and the Earth's center. This indicates the satellite's orbital angular velocity. This indicates the orbital inclination of the satellite. Indicates time. The phase factor represents the Walker constellation. This indicates the number of satellites in each orbit. This represents the total number of orbits contained within the constellation. The position vector formula described above fully describes the trajectory of a satellite in three-dimensional space and is the basis for calculating the link distance and pointing angle between any two satellites.

[0082] In a preferred embodiment, during the initial constellation deployment phase, a candidate connection matrix for inter-satellite links is pre-calculated based on the orbital parameters determined by the Walker constellation labeling method. Each element in the candidate connection matrix indicates whether a line-of-sight link exists between two satellites at a specified time, i.e., whether the Earth obstructs the link, and whether the link distance is within the working range of the laser terminal. This candidate connection matrix serves as the basis for inter-satellite link topology planning, used to pre-calculate alternative link schemes before topology changes, thus shortening the computational latency during topology reconstruction.

[0083] Furthermore, the real-time inter-satellite link distance between any two satellites is calculated from the difference magnitude of the position vectors of the two satellites' inertial coordinate systems; the elevation angle and azimuth angle required for the inter-satellite link transmitting optical terminal are obtained by jointly solving the orbital phase difference, orbital inclination, and the distance between the ascending nodes of the orbital plane of the two communication satellites.

[0084] Specifically, let the satellite network system be the first The first one in the track The satellite needs to be with the first The first one in the track Two satellites establish an inter-satellite laser link. The position vectors of the two satellites are respectively... and Then the link distance Let be the magnitude of the vector difference between the positions of the two satellites, i.e.:

[0085] (5)

[0086] Substituting the aforementioned position vector formulas (2), (3), and (4) into formula (5), we can obtain the analytical expression for the change of link distance over time:

[0087] (6)

[0088] This distance determines the propagation delay and spatial loss of the inter-satellite link, and is a core input parameter for link budget and power control.

[0089] The elevation and azimuth angles of the launching satellite are calculated jointly from the orbital phase difference, orbital inclination, and the distance between the ascending nodes of the two satellites. Let the orbital phase of the launching satellite be... The orbital phase of the receiving satellite is The distance between the ascending nodes of the two satellite orbital planes is Then the pitch angle The calculation formula is:

[0090] (7)

[0091] in:

[0092] (8)

[0093] (9)

[0094] In the formula, Indicates the first The first one in the track The orbital phase of a satellite. Indicates the first The first one in the track The orbital phase of a satellite. This indicates the distance between the ascending nodes of two satellites' orbital planes. (Pitch angle) The physical meaning of is the angle between the aiming vector of the satellite's transmitting antenna and the tangent direction of the orbital plane, and this angle changes periodically with the satellite's motion.

[0095] Azimuth The calculation formula is:

[0096] (10)

[0097] in This indicates the angular distance between two satellites on a great circle. Azimuth angle. The physical meaning of is the angle between the satellite velocity vector and the tangent direction of the great circle arc, reflecting the pointing trend of the inter-satellite link transmitting antenna in the azimuth direction.

[0098] The above formulas describe the complete variation of inter-satellite link distance and pointing angle with constellation parameters and time, and serve as the theoretical basis for neighbor discovery, link switching, and antenna pointing control in dynamic networking protocols. In practical systems, satellites can pre-calculate the trends of link distance and pointing angle changes with neighboring satellites over a future period based on the above formulas and their own ephemeris information. This allows them to adjust the pointing mechanism of the optical terminal in advance, ensuring rapid establishment and continuous locking of acquisition, alignment, and tracking functions.

[0099] In a preferred embodiment, the laser link terminal of a satellite node performs time-sharing pointing switching between candidate links according to a preset topology plan and a schedule. This schedule is pre-calculated by the ground network controller based on ephemeris information and traffic predictions, and then distributed to each satellite node via a software-defined network control plane. While the satellite node is in orbit, it points its laser link terminal to a designated adjacent satellite at a preset time according to the schedule, and maintains this pointing after the link is established until the next switching time. This time-sharing pointing strategy effectively reduces mechanical fatigue and power consumption caused by continuous pointing and tracking of the laser link terminal, while ensuring the predictability and controllability of the inter-satellite link topology.

[0100] This invention also provides a satellite optical / microwave composite networking system network protocol architecture, including a standard system management unit, a protocol stack configuration unit, and an inter-satellite link management unit. The standard system management unit defines and maintains specifications across five dimensions: overall system standards, networking protocol standards, security and confidentiality standards, operation and maintenance management standards, and equipment and product standards. The protocol stack configuration unit configures the corresponding protocol stack layer structure according to the communication scenario between the user terminal and the broadband service center or the user terminal, including the deployment of the user link physical layer, space network link layer, network layer, transport layer, and application layer, as well as the activation of the space network tunnel protocol layer. The inter-satellite link management unit manages the laser link terminals of each satellite node, constrains each satellite node to establish at least two inter-satellite links, and calculates physical connectivity quantification parameters. Its advantages over existing technologies are the same as those described above, and will not be repeated here.

[0101] While the invention has been described herein with reference to specific embodiments, it should be understood that these embodiments are merely examples of the principles and applications of the invention. Therefore, it should be understood that many modifications can be made to the exemplary embodiments, and other arrangements can be designed without departing from the spirit and scope of the invention as defined by the appended claims. It should be understood that different dependent claims and features described herein can be combined in ways different from those described in the original claims. It is also understood that features described in conjunction with individual embodiments can be used in other described embodiments.

Claims

1. A network protocol architecture method for a satellite optical / microwave hybrid networking system, characterized in that, It includes three main parts: system standard architecture, protocol stack architecture, and inter-satellite link management architecture; The system standard architecture is divided into five dimensions: overall system standards, networking protocol standards, security and confidentiality standards, operation and maintenance management standards, and equipment and product standards. In the protocol stack architecture, the physical layer does not distinguish between the data plane and the control plane, and does not require the configuration of independent signaling beam resources. All control functions are completed by data-bearing signaling. The hierarchical control planes are divided as follows: the control planes of the physical layer and data link layer are responsible for managing user terminal access and handover; the network layer control plane is based on SDN software-defined networking technology to achieve full network operation management. The inter-satellite link management architecture requires each satellite node to establish at least two inter-satellite links to ensure network connectivity redundancy; a physical connectivity quantification parameter is introduced to characterize the inter-satellite laser topology connectivity capability, which is the percentage of the number of currently enabled laser link terminals within the topology relative to the total number of all available laser link terminals on the satellite.

2. The network protocol architecture method for a satellite optical / microwave composite networking system according to claim 1, characterized in that, The overall system standard includes standardized content on networking and functional architecture, engineering interfaces, application modes, system testing, and capability assessment methods; the networking protocol standard sets out transmission access systems, integrated satellite-ground routing and switching, inter-satellite networking, and service access adaptation specifications for multiple types of transmission links, and the transmission links include two types: Ka microwave links and laser inter-satellite links.

3. The network protocol architecture method for a satellite optical / microwave composite networking system according to claim 1, characterized in that, The security and confidentiality standards cover three categories of specifications: transmission encryption, access authentication and authorization, and security of space-ground network interconnection; the operation and maintenance management standards include satellite telemetry and control, space-ground collaborative management and control, network-wide management, and telemetry, telemetry and control interaction interface standards; the equipment and product standards specify the general technical requirements for handheld terminals, vehicle-mounted stations, portable stations, gateway stations, and supporting antennas.

4. The network protocol architecture method for a satellite optical / microwave composite networking system according to claim 1, characterized in that, The layered structure of the communication protocol stack between the user terminal and the broadband service center is as follows: On the user terminal side, from bottom to top, the user link physical layer, space network link layer, network layer, transport layer, and application layer are deployed sequentially; on the satellite side, the user link physical layer, space network link layer, space network tunnel protocol layer, and power supply link physical layer are deployed sequentially; on the broadband service center side, from bottom to top, the user link physical layer, space network link layer, network layer, transport layer, and application layer are deployed sequentially; the user terminal and the satellite connect through the user link air interface, and the satellite and the broadband service center complete data interaction through the power supply link.

5. The network protocol architecture method for a satellite optical / microwave composite networking system according to claim 1, characterized in that, The end-to-end communication protocol stack layered structure between user terminals is as follows: From bottom to top, the source user terminal side consists of the user link physical layer, space network link layer, network layer, transport layer, and application layer; the source satellite side includes the user link physical layer, space network link layer, and inter-satellite link physical layer; the relay satellite has inter-satellite link physical layers deployed on both sides, with a space network tunnel protocol layer in the middle; the destination satellite side has inter-satellite link physical layers, space network link layer, and user link physical layers deployed in sequence; from bottom to top, the destination user terminal side consists of the user link physical layer, space network link layer, network layer, transport layer, and application layer; adjacent network nodes communicate through the user link air interface or the inter-satellite link air interface.

6. The network protocol architecture method for a satellite optical / microwave composite networking system according to claim 1, characterized in that, The core functions of the physical layer include physical frame assembly, signal modulation and demodulation, channel encoding and decoding, and physical layer link measurement; all operating parameters of the satellite-side physical layer are uniformly configured by the ground network controller; the core functions of the data link layer include radio resource scheduling, logical channel and transmission channel mapping, power and time-frequency joint control, service data multiplexing / demultiplexing, data segmentation, reordering, and concatenation processing; the terminal access control, radio connection management, and mobility management functions corresponding to the data link layer adopt a satellite-ground collaborative joint implementation mode.

7. The network protocol architecture method for a satellite optical / microwave composite networking system according to claim 1, characterized in that, The maximum network degree of freedom of a single satellite node is determined by the number of laser link terminals carried by the satellite; when all laser link terminals of the satellite establish inter-satellite links and occupy them, the resulting inter-satellite network topology is a two-way Manhattan street network.

8. The network protocol architecture method for a satellite optical / microwave composite networking system according to claim 1, characterized in that, The Walker constellation labeling method is used to model the satellite distribution within the constellation, and the real-time spatial position of each satellite in the inertial coordinate system is solved based on the constellation's basic parameters; the phase offset of the nearest satellite in adjacent orbital planes is uniquely determined by the constellation phase factor.

9. The network protocol architecture method for a satellite optical / microwave composite networking system according to claim 8, characterized in that, The real-time inter-satellite link distance between any two satellites is calculated from the difference magnitude of the position vectors in the inertial coordinate systems of the two satellites; the elevation angle and azimuth angle required for the inter-satellite link to transmit the optical terminal are obtained by jointly solving the orbital phase difference, orbital inclination, and the distance between the ascending nodes of the orbital plane of the two communication satellites.

10. A network protocol architecture system for a satellite optical / microwave composite networking system, characterized in that, include: The standard system management unit is used to define and maintain the specifications in five dimensions: overall system standards, networking protocol standards, security and confidentiality standards, operation and maintenance management standards, and equipment and product standards. The protocol stack configuration unit is used to configure the protocol stack architecture. In the protocol stack architecture, the physical layer does not distinguish between the data plane and the control plane, and there is no need to configure independent signaling beam resources. All control functions are completed by data-bearing signaling. In the physical layer and data link layer, the control plane is used to complete the access and handover management of user terminals. In the network layer, the control plane realizes the operation management of the entire network based on software-defined networking technology. The inter-satellite link management unit is used to manage the inter-satellite link architecture, constrain each satellite node to establish at least two inter-satellite links to ensure network connectivity redundancy, and calculate physical connectivity quantification parameters. The physical connectivity quantification parameters are the percentage of the number of currently enabled laser link terminals in the topology to the total number of all available laser link terminals on the satellite.

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