Satellite network single event upset fault ground multi-level simulation method and device

Abstract

This invention discloses a multi-level ground-based simulation method and apparatus for single-event upset (SEI) faults in satellite networks, primarily addressing the difficulty in simulating the impact of SEI on satellite systems and faults in existing technologies. The solution involves: dividing the laser communication satellite system into different subsystems; calculating the flip-off rate of core components using a SEI environment model and mapping it to the subsystem failure rate; generating multiple types of fault events and their probabilities by combining the internal fault mechanisms of each subsystem; establishing a fault state transition diagram between subsystems to calculate the joint fault probability, and constructing a multi-level single-satellite fault generation system accordingly; and forming a network-wide fault output based on the single-satellite fault generation system and combining constellation topology and link rules to achieve real-time fault simulation of large-scale satellite constellations. This invention can effectively realize the dynamic generation and simulation of SEI effects on single-satellite and network-wide faults based on a real space radiation environment, and can be used for large-scale constellation reliability assessment and design optimization.

Description

Technical Field

[0001] This invention belongs to the field of satellite communication technology, and specifically relates to a ground-based multi-level simulation method and device, which can be used for real-time high-fidelity fault generation and simulation of large-scale constellations in a single-event flip space radiation environment. Background Technology

[0002] With the continuous expansion of satellite networks and the increasing demand for high reliability in space information systems, building a high-precision space environment effect modeling and simulation technology system has become an urgent need for accurate fault analysis and reliable performance assessment of on-orbit satellite systems. Statistics show that satellite faults induced by the space environment account for 40% of all satellite faults, and single-event upsets (SEIs) caused by high-energy charged particles alone can account for more than 40% of all faults, posing a severe challenge to the stable operation of satellite networks. Accurate simulation and impact analysis of SEI environmental effects are of great significance to the stable operation of satellite networks. Therefore, it is imperative to establish a modeling method for mapping space environment effects and network faults to SEIs to achieve reliability assessment and assurance for large-scale constellations.

[0003] Patent application CN201910882312.2 discloses a satellite single-event flip (SET) monitoring method based on a monolithic array particle detector. This method designs a particle detector near the satellite detector to obtain the high-energy particle environment at the location of the SET-sensitive device, thereby determining the correlation between satellite anomalies and high-energy particles in space, and achieving on-orbit monitoring of the SET effect of the satellite's sensitive device. However, this method only achieves online monitoring of SETs and does not establish a fault damage model for the laser inter-satellite link caused by SETs.

[0004] Patent application CN202411867634.7 discloses a fault simulation device, system, and method for single-event upsets (SWEs). It uses fault injection technology on the ground to simulate SWEs, designs a fault diagnosis module to determine the fault type, and performs fault recovery in a fault recovery module. However, this method cannot simulate concurrent upsets of multiple devices in space radiation events, and it does not study the coupling relationships between various systems in laser satellite communication, thus failing to output a comprehensive damage fault model of SWEs to the satellite network.

[0005] Patent application CN202411835330.2 discloses an analytical assessment method for the risk of single-event upset (SWE) in aerospace electronic devices caused by solar proton events. It calculates the SWE measurement parameters by measuring the SEU cross-section of the target device and the proton radiation flux of the SPE, and then assesses and classifies the SEU risk caused by the SPE based on the calculation results. However, this method does not output the potential damage that SWE may cause to laser satellite communication system links and networks. Summary of the Invention

[0006] The purpose of this invention is to address the shortcomings of the prior art by proposing a ground-based multi-level simulation method and apparatus for single-event upset (SED) faults in satellite networks. This method aims to accurately model the fault damage of laser satellite communication systems under the influence of SED environments, forming a multi-level fault generation system for satellite communication systems covering functional, node, and protocol levels, thereby enabling large-scale satellite constellation fault generation and real-time simulation.

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

[0008] 1. A ground-based multi-level simulation method for single-event flip faults in satellite networks, characterized by comprising:

[0009] (1) Based on the composition of the laser satellite communication system, the system is divided into key subsystems such as the satellite computer, the optical antenna subsystem, and the optical transceiver system;

[0010] (2) For each laser satellite communication system subsystem that is susceptible to single-event upset, the single-event upset rate of its core components under different orbital and time conditions is calculated using a single-event upset space radiation environment model.

[0011] (3) Map the device-level single-event upset rate to the subsystem failure rate, and generate multiple types of fault events such as link performance degradation, link interruption and node failure based on the subsystem failure rate and its internal fault impact mechanism.

[0012] (4) Establish fault state transition diagrams between subsystems, simulate the transmission and evolution of faults between subsystems, calculate the joint fault probability of different subsystems based on the fault rate of the subsystems, and form a multi-level single-star fault generation system.

[0013] (5) Based on the multi-level single-satellite fault generation system, and combined with the real-time distribution of constellation satellites, generate network-wide fault samples to obtain network-wide fault output that conforms to the actual space radiation environment, and realize real-time fault simulation of large-scale satellite constellations in complex space radiation environment.

[0014] Furthermore, the establishment of fault state transition diagrams between subsystems in (4) includes the following implementation:

[0015] 4a) Based on the fault state transitions and steady-state probabilities within each subsystem and the functional dependencies between the subsystems within the single-star system, determine the possible fault types and propagation paths between the subsystems;

[0016] 4b) The fault states and their combinations of each subsystem are used as nodes in the single-star system-level state transition diagram, and the fault triggering, propagation and recovery relationships between subsystems are used as edges to obtain the fault state transition diagram between subsystems.

[0017] Furthermore, in step (4), the joint failure probability of different subsystems is calculated based on the failure rate of the subsystem to form a multi-level single-star failure generation system, the implementation of which includes:

[0018] 4c) Using the fault states and their transition relationships in the fault state transition diagram between subsystems, a single-star system-level Markov model is constructed to describe the probabilistic transition law of fault states between subsystems.

[0019] 4d) Solve the single-star system-level Markov model to obtain the steady-state probability of the single star under each joint failure state, that is, the joint failure probability of different subsystems.

[0020] 4e) Map the joint fault state of the single-satellite system to specific fault events, including link performance degradation, link interruption and node failure events;

[0021] 4f) Classify and organize fault events according to their impact at the functional, node, and protocol levels to form a multi-level fault generation system covering the entire single-satellite system.

[0022] 2. A ground-based multi-level simulation device for single-event flip faults in satellite networks, characterized in that it comprises:

[0023] The single-event upset environment calculation module is used to calculate the single-event upset rate of core components of each subsystem under different orbital and time conditions based on the space radiation environment model.

[0024] The single-star subsystem fault modeling module is used to map the device-level single-event upset rate to the subsystem failure rate, and generate multiple types of fault events, including link performance degradation, link interruption and node failure, based on the subsystem failure rate and its internal fault impact mechanism.

[0025] The single-star fault generation module is used to construct the fault state transition relationship between subsystems, calculate the joint fault probability of different subsystems, and generate a multi-level single-star fault generation system covering the functional level, node level, and protocol level.

[0026] The network-wide fault generation module is used to generate network-wide fault samples, enabling the expansion of faults within the satellite network.

[0027] Compared with the prior art, the present invention has the following advantages:

[0028] Firstly, this invention models hierarchical faults from the device level, subsystem level to single-satellite system level based on the composition structure of laser satellite communication systems. By mapping the single-event flip rate to the subsystem failure rate and combining the internal fault influence mechanism of the subsystem and the fault state transition relationship between subsystems, it generates multiple types of fault events covering the functional level, node level and protocol level, realizing a realistic mapping from the space radiation environment to system-level faults. Compared with existing fault analysis methods that only focus on the device level or use empirical formulas, this invention can better fit the actual space radiation environment and has higher physical realism and modeling completeness.

[0029] Secondly, based on single-satellite fault modeling, this invention further extends fault modeling from single-satellite to network-wide levels. By combining the real-time distribution of constellation satellites to generate network-wide fault samples, it achieves dynamic fault simulation of large-scale satellite networks in complex space environments. Compared to traditional static fault injection methods, this invention can reflect multi-node concurrent faults and their network-level propagation characteristics, realizing dynamic fault simulation from single-satellite to network-wide levels. This provides a supporting tool for reliability analysis and design optimization of arbitrary constellation configurations in complex space environments. Attached Figure Description

[0030] Figure 1 This is a flowchart illustrating the implementation of the ground-based multi-level simulation method for single-event flip faults in satellite networks according to the present invention.

[0031] Figure 2 This is a diagram of the laser communication satellite system used in the method of this invention;

[0032] Figure 3 This is the 1150km global single-event flip rate map in the method of this invention;

[0033] Figure 4 This is a block diagram of the ground-based multi-level simulation device for single-event flip faults in satellite networks according to the present invention. Detailed Implementation

[0034] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0035] Example 1: Ground-based multi-level simulation method for single-event flip faults in satellite networks

[0036] Reference Figure 1 The implementation steps of this example include the following:

[0037] Step 1: Select a laser communication satellite system.

[0038] The laser communication satellite system refers to a complex spacecraft system that uses a laser beam as a carrier to achieve high-speed information transmission between satellites or between satellites and ground in a space environment. Depending on the application scenario and mission payload, laser communication satellites have various different structural configurations.

[0039] This example uses a modular multi-link laser network node architecture, such as... Figure 2 As shown, this laser communication satellite system consists of multiple subsystems, including an optical antenna subsystem, an optical transceiver subsystem, an ATP (Automatic Train Protection) subsystem, a signal processing subsystem, an onboard routing subsystem, a telemetry command subsystem, a position and attitude control subsystem, an orbit insertion and propulsion subsystem, a temperature control subsystem, and a power supply subsystem. Among these, the optical transceiver subsystem, the signal processing subsystem, the onboard routing subsystem, and the ATP subsystem are critical subsystems that are susceptible to single-event upsets caused by high-energy particle impacts, which can lead to system malfunction.

[0040] Step 2: Establish a single-particle flip environment model.

[0041] Since the core components of the optical transceiver, signal processing, spaceborne routing, and ATP subsystems are susceptible to single-event upsets (SEORs) that can lead to subsystem malfunctions, it is necessary to construct a space radiation environment model. Starting from the physical environment of the core components, this model quantifies and analyzes the SEOR rate under different orbital positions and time conditions, providing physical support for subsequent subsystem-level failure probability models. Its implementation includes:

[0042] 2.1) Obtain the proton differential energy spectrum in the single-particle flip space radiation environment model. Heavy ion LET spectrum ;

[0043] 2.2) Obtain cross-sectional data of the core components through ground simulation experiments and perform curve fitting:

[0044] For the proton cross section, the Bendel two-parameter model is used for fitting:

[0045] ,

[0046] For the heavy ion cross section, the Weibull model is used for fitting:

[0047] ,

[0048] in, For the proton cross section, Let A be the normalized ratio of the incident proton's energy parameter to the critical threshold required for the device to trigger a single-event upset, and E be the incident proton energy. This is the single-particle overturning limit section; This is a cross-section of a heavy ion device. 0 represents the saturation cross-section at which the device flips, L is the LET value, and L0 is the minimum LET value at which a single-event upset occurs. is the size factor of the Weibull distribution, and s is the shape factor;

[0049] 2.3) Based on the proton differential energy spectrum and proton cross section Calculate the proton single-particle flip rate :

[0050] ,

[0051] Where E0 is the single-particle flip proton energy threshold, E max This represents the maximum energy of a space proton.

[0052] 2.4) Based on heavy ion LET spectra and heavy ion cross section Calculation of heavy ion single-event flip rate :

[0053] ,

[0054] Among them, L max This represents the maximum LET value for heavy ions in space.

[0055] 2.5) Based on the proton single-particle flip rate R P and heavy ion single-event flip rate R h The total device-level single-event flip rate R was calculated as follows:

[0056] .

[0057] In this embodiment of the invention, the satellite constellation is set to 12 orbital planes with 9 satellites per orbit, an orbital altitude h = 1150 km, and an inclination i = 53°. Using the onboard routing subsystem FPGA as the core device, a global single-event flip rate map of the device at 04:00 on March 23, 2026, is obtained through numerical integration, as shown below. Figure 3 As shown, the single-event flip rate at longitude 20.716° and latitude -36.367° is... times per (bit·second).

[0058] Step 3: Implement subsystem fault simulation.

[0059] Because the various subsystems of a satellite differ in structure and function, their fault states and manifestations vary. Therefore, it is necessary to model each subsystem separately to obtain its corresponding set of fault states and their probabilities, generate different types of fault events, and thus complete the satellite subsystem fault simulation. This provides a foundation for subsequent single-satellite system fault simulation.

[0060] The following fault simulation uses the onboard routing subsystem as an example, and its implementation includes:

[0061] 3.1) Based on the fact that the probability of a single-event flip occurring in a single storage bit follows a Poisson distribution and the single-event flip rate... Characteristics, calculate the device-level failure rate within time period t. :

[0062] ,

[0063] in, Where is the device-level single-event upset rate, and N is the number of sensitive bits of the device;

[0064] In this embodiment, the FPGA sensitive bit depth of the spaceborne routing subsystem is [number] bits. Then the device-level single-event flip rate = / s, within the time interval 𝑡, the device-level failure rate .

[0065] 3.2) Based on device-level failure rate Calculate the subsystem failure rate :

[0066] ,

[0067] in, This represents the device-level failure rate of the i-th core device in the subsystem, where k indicates that there are k core devices in the subsystem.

[0068] In this embodiment, the spaceborne routing subsystem has two core devices: an FPGA and a CPU. Taking t=1, the FPGA device-level failure rate is... The CPU device-level failure rate was calculated using the same method. The failure rate of the spaceborne routing subsystem is p=0.039.

[0069] 3.3) Based on the subsystem's failure rate and its internal failure impact mechanism, generate multiple types of failure events, including link performance degradation, link interruption, and node failure:

[0070] 3.3.1) Based on the device structure and functional characteristics of the subsystem, analyze the impact of each device failure on the subsystem function and generate a set of specific failure states that may occur in the subsystem.

[0071] In this embodiment, the onboard routing subsystem may be in a normal state of S0. Possible faults include link loss D1, pseudo-node D2, and pseudo-link D3 caused by faults during the route discovery phase; destination entry error U1, next-hop entry error U2, and unknown port U3 caused by faults during the route update phase; and destination error F1, next-hop error F2, and packet loss F3 caused by faults during the route forwarding phase. The possible system state set is S0.R ={S0, D1, D2, D3, U1, U2, U3, F1, F2, F3}.

[0072] 3.3.2) Using the possible fault states of the subsystem as nodes, establish a Markov model of the subsystem based on the state transition probability to describe the evolution mechanism of the fault states within the subsystem;

[0073] In this embodiment, the set S R The state of the node is used as the initial stimulus based on the real-time subsystem failure rate p calculated in step 3.2). A Markov model is established by combining the logical jump relationship of each protocol stage. This model dynamically describes the stochastic process of the spaceborne routing system transitioning from a normal state to a state with impaired functions.

[0074] 3.3.3) Solve the Markov model of the subsystem to obtain the steady-state probability of the subsystem under each fault state;

[0075] In this embodiment, the Markov model described above is solved by matrix calculation to obtain the steady-state probabilities of different fault states.

[0076] 3.3.4) Generate different types of fault events based on the device's operating principle and the steady-state probability under various fault conditions:

[0077] When a fault condition causes a decrease in link bandwidth, an increase in latency, or an increase in bit error rate, it is determined as a degraded link performance.

[0078] When a fault condition causes a link to fail to be established or communication to be interrupted, it is determined to be a link interruption;

[0079] When a fault condition causes the entire satellite node to be unable to provide services, it is determined to be a node failure.

[0080] In this embodiment, when the system is in the F3 or U3 state, the effective throughput decreases or the latency fluctuates, which is determined to be a link performance degradation; when the system is in the D1, D2, U2, or F2 state, the local logical link cannot be established or the communication is abnormally disconnected, which is determined to be a link interruption; when the system is in the D3, U1, or F1 state, the satellite node routing function fails, which is determined to be a node failure. The probabilities of the three types of events are calculated respectively, thereby completing the construction of the subsystem fault model.

[0081] Referring to the above-mentioned fault simulation method for the spaceborne routing subsystem, fault simulation can be performed on the optical transceiver, signal processing, and ATP subsystems. Corresponding models can be constructed according to their functional characteristics and fault characteristics, and output link performance degradation, link interruption, node failure fault events and their corresponding probabilities.

[0082] Step 4: Simulate the faults of the laser communication satellite system.

[0083] Because the various subsystems within a laser communication satellite system are functionally interdependent, their faults are not only localized but can also transfer or cascade within the system through these dependencies. Therefore, it is necessary to simulate the faults of the laser communication satellite system based on the fault simulation of the subsystems to describe the overall fault behavior and probabilistic evolution characteristics of the laser communication satellite system. This will enable single-star fault simulation and provide a foundation for subsequent network-wide fault simulation. The implementation includes:

[0084] 4.1) Based on the fault state transitions, steady-state probabilities, and functional dependencies of each subsystem of the laser communication satellite system, determine the possible fault types and propagation paths between subsystems, and establish a fault state transition diagram for the laser communication satellite system.

[0085] In this embodiment, the spaceborne routing subsystem and the optical transceiver subsystem are selected as the research objects, wherein:

[0086] The optical transceiver subsystem is responsible for maintaining the physical laser link, while the spaceborne routing subsystem is responsible for addressing the logical path. It relies on the physical link provided by the optical transceiver subsystem for topology discovery, route calculation, and forwarding. The state set of the spaceborne routing system is set S as described in step 3.3.1). R ;

[0087] The optical transceiver subsystem may have the following states: normal state O0, decreased optical power O1, acquisition / tracking failure O2, and link interruption O3. Therefore, the set of states for the optical transceiver subsystem is S. O ={O0,O1,O2,O3};

[0088] The dependency relationship between the spaceborne routing subsystem and the optical transceiver subsystem, with a joint fault state of S={S R S O The fault transfer relationships are (S0, O0), (D1, O3), (F3, O1)}, (S0, O0), (D1, O3), (F3, O1)}, (S0, O0) transfers to (S0, O1), then to (F3, O1), and finally to (U2, O1). Any state transfers to (S0, O0). A fault state transfer diagram for the laser communication satellite system is established based on the joint fault states and their fault transfer relationships.

[0089] 4.2) Using the fault states and their transition relationships in the fault state transition diagram between subsystems, a Markov model of the laser communication satellite system is constructed to describe the probability transition law of fault states between subsystems. The Markov model of the laser communication satellite system is solved to obtain the steady-state probability of the satellite under each joint fault state, that is, the joint fault probability of different subsystems.

[0090] In this embodiment, a Markov model is used to model the fault state transition diagram of the laser communication satellite system. The state transition matrix Q is defined and solved. The combined failure probability of different subsystems is obtained.

[0091] 4.3) Map the joint fault state of the laser communication satellite system into specific fault events, including link performance degradation, link interruption and node failure events. Classify and organize the fault events according to their impact at the functional level, node level and protocol level, thereby forming a multi-level fault generation system covering the functional level, node level and protocol level of the laser communication satellite system.

[0092] In this embodiment, the joint fault states of the laser communication satellite system are classified according to the classification rules in step 3.3.4), and the probabilities of link performance degradation, link interruption, and node failure events are calculated. The system state probabilities are mapped to the interval [0,1], and a random number pool is created. In each time slot, a random number is generated, and it is determined whether it belongs to the random number pool. If it does, the satellite is determined to be in a fault state in the current time slot, and the specific fault event is generated based on the random number. If the random number does not belong to the random number pool, the satellite is determined to be in a normal state. Through the above mechanism based on probability mapping and random sampling, the fault state determination and fault event generation of the laser communication satellite system are realized, thereby completing the dynamic simulation of single-satellite faults.

[0093] Step 5: Perform real-time dynamic simulation of network-wide faults.

[0094] The network-wide fault model refers to simulating the fault states of all satellite nodes and their inter-satellite links under given time and space conditions at the satellite constellation network level. Faults not only affect the operational status of each individual satellite node but can also propagate and couple across the entire network via inter-satellite links, forming more complex system-level fault effects. Therefore, based on the fault simulation of laser communication satellite systems, it is necessary to combine link connection relationships and topology to simulate network-wide faults, characterizing the propagation and time-varying process of faults within the satellite constellation. This provides support for large-scale constellation system fault simulation and reliability assessment. The implementation steps include:

[0095] 5.1) Based on the fault generation system of laser communication satellite system, obtain the single-satellite multi-type fault events and their occurrence probabilities under the real-time orbital position and link topology of each satellite;

[0096] In this embodiment, based on the fault generation system of the laser communication satellite system, the status information of each satellite at the current moment is obtained: for example, the fault status of satellite 1 in orbit 1 at the current moment is performance degradation, satellite 2 in orbit 1 is normal, and satellite 3 in orbit 1 is link interrupted.

[0097] 5.2) Integrate all satellite failure events, combine satellite link connection methods and satellite topology, correct the correlation of satellite failure events, and map single satellite failure events to the entire satellite constellation network to generate network-wide failure status;

[0098] In this embodiment, when either of the two satellites connected by a link fails and causes a communication interruption, the link is determined to be in a link interruption state, thereby affecting the communication path of adjacent satellites; based on the above correction, the single-satellite failure event is mapped to the entire network to generate a network-wide failure state set.

[0099] 5.3) Continuously update the network-wide fault status according to time steps to realize dynamic real-time fault generation of large-scale satellite constellations in complex space radiation environment.

[0100] In this embodiment, a time step is set. The system updates the overall network fault status step by step. Within each time step, the fault status is resampled or updated based on the satellite fault probability, and the fault distribution across the entire network is updated in conjunction with changes in link topology. For example, in the next time step, 3 satellites in 5 orbits recover from link interruption, while 7 satellites in 10 orbits experience link performance degradation, thus forming a new overall network fault status. Through continuous iterative updates, dynamic real-time fault generation of large-scale satellite constellations in complex space radiation environments is achieved.

[0101] Example 2: Ground-based multi-level simulation device for single-event flip fault in satellite networks.

[0102] Reference Figure 4 This embodiment includes: a single-event upset environment calculation module 1, a single-star subsystem fault simulation module 2, a single-star fault generation module 3, and a network-wide fault generation module 4. Specifically, the single-event upset environment calculation module 1 includes a differential energy spectrum acquisition submodule 11, a cross-sectional data acquisition submodule 12, and a single-event upset rate calculation submodule 13; the single-star subsystem fault simulation module 2 includes a single-star subsystem fault modeling submodule 21 and a single-star subsystem fault event generation submodule 22; the single-star fault generation module 3 includes a single-star system fault modeling submodule 31, a joint probability calculation submodule 32, and a single-star fault generation submodule 33; and the network-wide fault generation module 4 includes a constellation mapping submodule 41, a network-wide fault generation submodule 42, and a fault update submodule 43.

[0103] The working principle of the entire system is as follows:

[0104] The single-event upset environment calculation module 1 is used to calculate the device-level single-event upset rate. The differential energy spectrum acquisition submodule 11 is used to acquire the proton and heavy ion energy spectrum distribution under the target orbit and transmit the spectrum data to the cross-sectional data acquisition submodule 12. The cross-sectional data acquisition submodule 12 is used to acquire and process single-event upset cross-sectional data and transmit the cross-sectional data to the single-event upset rate calculation submodule 13. The single-event upset rate calculation submodule 13 is used to combine the differential energy spectrum and cross-sectional data to calculate the device-level single-event upset rate within a given time period and output the result to the single-star subsystem fault modeling module 2.

[0105] The single-satellite subsystem fault simulation module 2 is used to simulate the fault states of each subsystem of the satellite. The single-satellite subsystem fault modeling submodule 21 calculates the fault probability and state set of each subsystem within a certain time interval based on the subsystem's functional structure and device-level single-event upset rate. The single-satellite subsystem fault event generation submodule 22 classifies and abstracts the fault states, generates specific subsystem fault events, and transmits the events and their probability information to the single-satellite fault generation module 3.

[0106] The single-satellite fault generation module 3 is used to construct a single-satellite system-level joint fault model. The single-satellite system fault modeling submodule 31 establishes a single-satellite system-level fault state transition diagram based on the fault states of subsystems and the functional dependencies between subsystems. The joint probability calculation submodule 32 establishes a Markov model based on the state transition diagram and calculates the joint fault probability of different subsystems. The single-satellite fault generation submodule 33 maps the joint fault state to specific fault events, such as link performance degradation, link interruption and node failure events, and transmits the generated single-satellite fault events to the network-wide fault generation module 4.

[0107] The network-level fault generation module 4 is used to realize constellation-level fault simulation. The constellation mapping submodule 41 maps each individual satellite fault event to the entire satellite network; the network-level fault generation submodule 42 corrects the mapping results for correlation and generates the network-level fault state; the fault update submodule 43 continuously updates the network-wide fault state according to time steps, realizing the dynamic fault generation and evolution simulation of large-scale constellation systems in complex space radiation environments, and providing support for satellite network reliability assessment and risk analysis.

[0108] Through the coordinated work of the above modules, this system can efficiently simulate single-satellite faults and can generate and dynamically simulate network-wide faults for any laser communication satellite constellation configuration, ensuring that the output fault structure truly reflects the fault state distribution of the constellation system in a complex space environment.

[0109] It should be noted that the above functional modules can be implemented, in whole or in part, through software, hardware, firmware, or any combination thereof. When implemented in software, they can be implemented, in whole or in part, as program instruction products. A program instruction product includes one or a set of program instructions. When the program instructions are loaded and executed on a computer, the described process or function is generated, in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The program instructions can be stored in a computer-readable and writable storage medium, or transferred from one computer's readable and writable storage medium to another.

[0110] In this embodiment, direct coupling or communication connections between modules can be achieved through indirect coupling or communication connections via interfaces, devices, or modules. The functional modules and sub-modules in this embodiment can dynamically reside within a single processing unit, or each module can exist physically independently, or two or more modules can dynamically reside within a single processing unit. When these dynamic components are implemented as software functional modules and sold or used as independent products, they can also be stored in a computer-readable and writable storage medium. This storage medium can be a memory, disk, or optical disc, etc.

[0111] The above descriptions are merely a few specific examples of the present invention and do not constitute any limitation on the present invention. Obviously, those skilled in the art, after understanding the content and principles of the present invention, may make various modifications and changes in form and detail without departing from the principles and structure of the present invention. For example, the single-event upset rate can be obtained not only through the calculation formula of the present invention but also based on on-orbit experimental data; the fault state division and fault transfer relationship used in the subsystem and single-satellite fault simulation can be adjusted according to the device and system structure and function, in addition to the fault state division and fault transfer relationship used in the present invention; the network-level fault mapping and dynamic update process can be adjusted according to the actual topology and dynamic routing strategy of different constellation configurations, in addition to the constellation topology and link association rules used in the present invention. However, these modifications and changes based on the ideas of the present invention are still within the scope of protection of the claims of the present invention.

Claims

1. A ground-based multi-level simulation method for single-event flip faults in satellite networks, characterized in that, include: (1) Based on the composition structure of the laser satellite communication system, the system is divided into the following subsystems: optical antenna subsystem, optical transceiver subsystem, ATP subsystem, signal processing subsystem, on-board routing subsystem, telemetry command subsystem, position and attitude control subsystem, orbit insertion and propulsion subsystem, temperature control subsystem, and power supply subsystem. (2) For each laser satellite communication system subsystem that is susceptible to single-event upset, the single-event upset rate of its core components under different orbital and time conditions is calculated using a single-event upset space radiation environment model. (3) Map the device-level single-event upset rate to the subsystem failure rate, and generate multiple types of fault events such as link performance degradation, link interruption and node failure based on the subsystem failure rate and its internal fault impact mechanism. (4) Establish fault state transition diagrams between subsystems, simulate the transmission and evolution of faults between subsystems, calculate the joint fault probability of different subsystems based on the fault rate of the subsystems, and form a multi-level single-star fault generation system. (5) Based on the multi-level single-satellite fault generation system, and combined with the real-time distribution of constellation satellites, generate network-wide fault samples to obtain network-wide fault output that conforms to the actual space radiation environment, and realize real-time fault simulation of large-scale satellite constellations in complex space radiation environment.

2. The method according to claim 1, characterized in that, In step (2), the single-event flip rate of the core device is calculated under different orbital and temporal conditions using a single-event flip space radiation environment model. The implementation of this method includes: 2a) Obtain the proton differential energy spectrum in the single-particle flip space radiation environment model Heavy ion LET spectrum ; 2b) Obtain cross-sectional data of core components through ground simulation experiments and perform curve fitting: For the proton cross section, the Bendel two-parameter model is used for fitting: ， For the heavy ion cross section, the Weibull model is used for fitting: ， in, For the proton cross section, Let A be the normalized ratio of the incident proton's energy parameter to the critical threshold required for the device to trigger a single-event upset, and E be the incident proton energy. This is the single-particle overturning limit section; This is a cross-section of a heavy ion device. 0 represents the saturation cross-section at which the device flips, L is the LET value, and L0 is the minimum LET value at which a single-event upset occurs. is the size factor of the Weibull distribution, and s is the shape factor; 2c) Based on the proton differential energy spectrum and proton cross section Calculate the proton single-particle flip rate : ， Where E0 is the single-particle flip proton energy threshold, E max This represents the maximum energy of a space proton. 2d) Based on heavy ion LET spectra and heavy ion cross section Calculation of heavy ion single-event flip rate : ， Among them, L max This represents the maximum LET value for heavy ions in space. 2e) Based on the proton single-particle flip rate R P and heavy ion single-event flip rate R h The total device-level single-event flip rate R was calculated as follows: 。 3. The method according to claim 1, characterized in that, The mapping of the device-level single-event upset rate to the subsystem failure rate in (3) is implemented as follows: 3a) Based on the fact that the probability of a single-event flip occurring in a single storage bit follows a Poisson distribution and the single-event flip rate Characteristics, calculate the device-level failure rate within time period t. : ， in, Where is the device-level single-event upset rate, and N is the number of sensitive bits of the device; 3b) Based on device-level failure rate Calculate the subsystem failure rate : ， in, This represents the device-level failure rate of the i-th core device in the subsystem, where k indicates that there are k core devices in the subsystem.

4. The method according to claim 1, characterized in that, In step (3), based on the failure rate of the subsystem and the failure impact mechanism within the subsystem, multiple types of failure events, including link performance degradation, link interruption, and node failure, are generated. The implementation of this includes: 3c) Based on the device structure and functional characteristics of the subsystem, analyze the impact of each device failure on the subsystem function and generate a set of specific failure states that may occur in the subsystem. 3d) Using the possible fault states of the subsystem as nodes, establish a Markov model of the subsystem based on the state transition probability to describe the evolution mechanism of the fault states within the subsystem. 3e) Solve the Markov model of the subsystem to obtain the steady-state probability of the subsystem under each fault state; 3f) Generate different types of fault events based on the device's operating principle and the steady-state probability under each fault state: When a fault condition causes a decrease in link bandwidth, an increase in latency, or an increase in bit error rate, it is determined as a degraded link performance. When a fault condition causes a link to fail to be established or communication to be interrupted, it is determined to be a link interruption; When a fault condition causes the entire satellite node to be unable to provide services, it is determined to be a node failure.

5. The method according to claim 1, characterized in that, The establishment of fault state transition diagrams between subsystems in (4) includes the following implementation: 4a) Based on the fault state transitions and steady-state probabilities within each subsystem and the functional dependencies between the subsystems within the single-star system, determine the possible fault types and propagation paths between the subsystems; 4b) The fault states and their combinations of each subsystem are used as nodes in the single-star system-level state transition diagram, and the fault triggering, propagation and recovery relationships between subsystems are used as edges to obtain the fault state transition diagram between subsystems.

6. The method according to claim 1, characterized in that, In step (4), the joint failure probability of different subsystems is calculated based on the failure rate of the subsystem to form a multi-level single-star failure generation system, the implementation of which includes: 4c) Using the fault states and their transition relationships in the fault state transition diagram between subsystems, a single-star system-level Markov model is constructed to describe the probabilistic transition law of fault states between subsystems. 4d) Solve the single-star system-level Markov model to obtain the steady-state probability of the single star under each joint failure state, that is, the joint failure probability of different subsystems. 4e) Map the joint fault state of the single-satellite system to specific fault events, including link performance degradation, link interruption and node failure events; 4f) Classify and organize fault events according to their impact at the functional, node, and protocol levels to form a multi-level fault generation system covering the entire single-satellite system.

7. The method according to claim 1, characterized in that, The process of generating network-wide fault samples based on a multi-level single-satellite fault generation system and the real-time distribution of constellation satellites in (5) includes the following: 5a) Based on the multi-level single-satellite fault generation system, obtain the single-satellite multi-type fault events and their occurrence probabilities for each satellite under real-time orbital position and link topology; 5b) Integrate all single-satellite failure events, combine satellite link connection methods and satellite topology, correct the correlation of single-satellite failure events, and map single-satellite failure events to the entire satellite constellation network to generate network-wide failure status; 5c) Continuously update the network-wide fault status according to time steps to realize dynamic real-time fault generation of large-scale satellite constellations in complex space radiation environment.

8. A ground-based multi-level simulation device for single-event flip faults in satellite networks, characterized in that, include: The single-event upset environment calculation module is used to calculate the single-event upset rate of core components of each subsystem under different orbital and time conditions based on the space radiation environment model. The single-star subsystem fault simulation module is used to map the device-level single-event upset rate to the subsystem fault rate, and generate multiple types of fault events, including link performance degradation, link interruption and node failure, based on the subsystem fault rate and its internal fault impact mechanism. The single-star fault generation module is used to construct the fault state transition relationship between subsystems, calculate the joint fault probability of different subsystems, and generate a multi-level single-star fault generation system covering the functional level, node level and protocol level. The network-wide fault generation module is used to generate network-wide fault samples, enabling the expansion of faults within the satellite network.

9. The system according to claim 8, characterized in that, The single-satellite fault generation module includes: The single-satellite system fault modeling submodule is used to construct a fault transfer model between subsystems based on the fault states and transfer relationships of each subsystem, forming a single-satellite system-level fault state space. The joint probability calculation submodule is used to calculate the joint failure probability of different subsystem failure combination states; The single-satellite fault generation submodule is used to generate multi-level single-satellite fault events covering the functional level, node level, and protocol level based on different subsystem combination states and joint fault probabilities.

10. The system according to claim 8, characterized in that: The single-event flip environment calculation module includes: The differential energy spectrum acquisition submodule is used to acquire the particle differential energy spectrum under different orbital and temporal conditions based on the space radiation environment model; The cross-sectional data acquisition submodule is used to acquire single-particle flip cross-sectional data of the core components of each subsystem and to process the cross-sectional data. The single-event upset rate calculation submodule is used to calculate the single-event upset rate of the core devices of each subsystem under different orbital and time conditions based on the particle differential energy spectrum and device cross-sectional data. The network-wide fault generation module includes: The constellation mapping submodule is used to map multi-level fault events of a single satellite to the entire satellite constellation network, and to perform correlation correction of the faults by combining link connection relationships and topology structure; The whole-network fault generation submodule is used to generate whole-network fault samples based on single-satellite fault events and their probabilistic characteristics, so as to realize the expansion of faults in the satellite network; The fault update submodule is used to dynamically update the network-wide fault samples according to time steps to obtain the continuously changing fault status of the entire network.

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