A communication system fault analysis method based on FTA and FMEA

Abstract

The application discloses a communication system fault analysis method based on FTA and FMEA, comprising the following steps: based on the MBSE method, an MBSE model of the communication system is established as the model basis of the system fault analysis; based on the MBSE model of the system, a function fault tree is established by using the FTA method to identify the hierarchical relationship between the function blocks of the system and perform fault analysis; based on the function fault tree, the important function blocks of each level are analyzed by using the FMEA method to generate the corresponding FMEA analysis table of each level; the function fault database of the communication system is established by comprehensively combining the function fault tree and the FMEA analysis table of each level of function blocks, and finally the fault analysis report of the system is generated. Through systematic design and hierarchical analysis, the application can comprehensively identify and analyze the system fault causes, improve the fault analysis efficiency, and significantly improve the reliability and performance of the system.

Description

Technical Field

[0001] This invention belongs to the field of communication systems and relates to communication system fault analysis, specifically to a communication system fault analysis method based on FTA and FMEA. Background Technology

[0002] Communication systems, as the core of modern information transmission, play a vital role in all walks of life. In recent years, with the rapid development of technology and the continuous growth of demand, the scale and complexity of communication systems have increased significantly. As a large and complex system, traditional fault analysis methods often fall short in dealing with such complex systems, not only consuming a lot of human, financial, and time resources, but also making it difficult to guarantee the comprehensiveness and accuracy of the analysis results. Summary of the Invention

[0003] Objective: To overcome the shortcomings of existing technologies, this invention provides a communication system fault analysis method based on FTA and FMEA. By combining Model-Based Systems Engineering (MBSE), Fault Tree Analysis (FTA), and Fault Mode and Effects Analysis (FMEA), a systematic design and fault analysis of the communication system is performed. By establishing a detailed MBSE model, potential faults at each level of the system are systematically identified and analyzed, forming a fault risk database and generating a fault analysis report. This improves fault analysis efficiency, rapidly identifies fault modes and causes, finds effective fault solutions, and significantly enhances system reliability and performance.

[0004] Technical Solution: To achieve the above objectives, this invention provides a communication system fault analysis method based on FTA and FMEA, comprising the following steps:

[0005] S1: Based on the MBSE methodology, establish an MBSE model for the communication system as the model basis for system fault analysis;

[0006] S2: Based on the MBSE model of the system, the FTA method is used to establish a functional fault tree, identify the hierarchical relationship between system functional blocks and perform fault analysis.

[0007] S3: Based on the functional fault tree, use the FMEA method to analyze the important functional blocks at each level and generate the corresponding FMEA analysis table for each level;

[0008] S4: Combine the integrated functional fault tree and FMEA analysis tables of each level of functional blocks to establish a functional fault database for the communication system, and finally generate a fault analysis report for the system.

[0009] Furthermore, the method for establishing the MBSE model of the communication system in step S1 is as follows: the MBSE method is used to model the system, and the modeling is divided into three levels: logical subsystem level, component level and interface level. The communication system is modeled from top to bottom from the three aspects of system structure, function and parameters. The logical subsystem level, component level and interface level are respectively used as the first design level, the second design level and the third design level from top to bottom.

[0010] Furthermore, in step S1, the communication system is modeled from top to bottom from three aspects: system structure, function, and parameters. Specifically, this includes:

[0011] B1: Model the structure of the communication system. At the logical subsystem level, the system is divided into three logical subsystems: access network, bearer network, and core network. At the component level, these logical subsystems are further decomposed into specific network elements. At the interface level, interfaces are added to the components, and the interfaces are divided into several protocol layers so that each component can communicate through the interfaces in a specified manner.

[0012] B2: The functions of the communication system are modeled. At the logical subsystem level, an activity diagram of the connection-state mobility management function is established, covering the function blocks of measurement reporting, terminal location reporting, intra-frequency handover, and inter-frequency handover. At the component level, taking the measurement reporting function block as an example, a sequence diagram of measurement reporting is established. At the interface level, taking the Uu-C interface on the UE side as an example, an activity diagram of the interface for sending data is established.

[0013] B3: The parameters of the communication system are modeled, and the system's service indicators are decomposed layer by layer from top to bottom, passing through the logical subsystem level, component level and interface level in turn, and finally implemented as service indicators at the protocol layer.

[0014] Furthermore, the method for establishing the functional fault tree in step S2 is as follows: select the logical subsystem level functional block in the MBSE model as the fault analysis object, and establish the functional fault tree.

[0015] Furthermore, step S3 specifically includes:

[0016] A1: Based on the functional fault tree and the MBSE model of the system, the connected mobility management functional block is used as the analysis object. The FMEA analysis method is used to perform FMEA analysis on the functional block at the first design level (logic subsystem level) to form an FMEA analysis table.

[0017] A2: After completing the FMEA analysis at the logical subsystem level, take the measurement reporting function block as the analysis object, combine the functional fault tree, MBSE model and the FMEA analysis results at the logical subsystem level, and use the FMEA analysis method to perform FMEA analysis on the function blocks at the second design level (component level) to form the corresponding FMEA analysis table.

[0018] A3: Following the component-level analysis, based on the functional fault tree, MBSE model, and FMEA analysis results of the component level, the data transmission function block of the Uu-C interface (UE side) is used as the analysis object. The FMEA analysis method is used to perform FMEA analysis on the function block of the third design level (interface level) to form the corresponding FMEA analysis table.

[0019] Furthermore, in the FMEA analysis table of step A1, the FMEA items include FMEA ID, FMEA name, current level behavior, failure mode, failure cause, next level behavior, upper level failure impact, previous level behavior, final failure impact, OCC (failure frequency), SEV (failure severity), and design improvement measures.

[0020] Furthermore, in the FMEA analysis table of step A2, the FMEA items include FMEA ID, FMEA name, current level behavior, network element, physical entity, fault mode, fault cause, next level behavior, interface, upper level fault impact, upper level behavior, final fault impact, OCC (fault occurrence frequency), SEV (fault impact severity), and design improvement measures.

[0021] Furthermore, in the FMEA analysis table of step A3, the FMEA items include FMEA ID, FMEA name, current level behavior, interface, physical entity, failure mode, failure cause, next level behavior, protocol layer specific behavior, protocol layer indicators, upper level failure impact, upper level behavior, final failure impact, OCC (failure frequency), SEV (failure severity), and design improvement measures.

[0022] Furthermore, in step S2, a functional fault tree for connected mobility management is established. The method for establishing the tree is as follows: an FMEA item for the connected mobility management function is established. This function is decomposed into four functional blocks at the component level: measurement reporting, terminal location reporting, inter-frequency handover, and intra-frequency handover. Subsequently, the functional blocks at the component level are further decomposed into functional blocks of various interfaces at the interface level, and the functional blocks of the interfaces are further refined into functional blocks of the protocol layer.

[0023] Fault tree analysis (FTA) is a top-down deductive failure analysis method widely used in safety engineering and reliability engineering. Through FTA, we can gain a deeper understanding of the causes of system failures, find the best risk reduction methods, or determine the probability of a safety incident or specific system failure, thereby enhancing system reliability.

[0024] Failure Mode and Effects Analysis (FMEA) is an analytical method used to identify potential failure modes and their causes. It is widely used to systematically assess and reduce the risk of potential failures. FMEA is managed in tabular form, including items such as number, name, item, failure cause, failure mode, partial failure effect, and final failure effect. The failure mode, which describes how a requirement, component, or function fails, is the core of the FMEA analysis. The failure cause leads to the failure mode, while the failure effect is the result of the failure mode.

[0025] This invention utilizes a model-based systems engineering (MBSE) approach to systematically design and model communication systems, establishing detailed MBSE models that provide a solid model foundation for fault analysis. Combining FTA and FMEA for fault analysis of communication systems allows for the creation of a fault risk database, improving fault analysis efficiency, rapidly identifying fault modes, and finding solutions, thereby optimizing system maintenance and management. Through the systematic design of the MBSE model, combined with the efficient fault analysis methods of FTA and FMEA, fault analysis of communication systems becomes not only more systematic and efficient but also significantly improves system reliability and performance, driving the continuous development of communication technology.

[0026] Beneficial effects: Compared with the prior art, this invention, through systematic design and modeling, hierarchical fault analysis, and combining FTA and FMEA methods, comprehensively identifies and analyzes the causes of communication system faults, establishes a detailed fault database and generates analysis reports, thereby significantly improving the reliability and performance of the system and enhancing the efficiency of fault management and maintenance. Attached Figure Description

[0027] Figure 1 This is a flowchart illustrating the method of the present invention.

[0028] Figure 2 A schematic diagram of a communication system modeling method based on MBSE.

[0029] Figure 3 This is a schematic diagram of the MBSE model of a communication system.

[0030] Figure 4 This is a schematic diagram of the parameters of the MBSE model for a communication system.

[0031] Figure 5This is a functional fault tree diagram of the connection-state mobility management function block in an embodiment of the present invention.

[0032] Figure 6 This is a schematic representation of the FMEA analysis of the connected mobility management function block in an embodiment of the present invention.

[0033] Figure 7 This is a schematic representation of the FMEA analysis of the measurement reporting function block in an embodiment of the present invention.

[0034] Figure 8 This is a schematic representation of the FMEA analysis of the Uu-C interface (UE) data transmission function block in an embodiment of the present invention. Detailed Implementation

[0035] The present invention will be further illustrated below with reference to the accompanying drawings and specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. After reading this invention, any modifications of the invention in various equivalent forms by those skilled in the art will fall within the scope defined by the appended claims.

[0036] like Figure 1 As shown, this invention provides a communication system fault analysis method based on FTA and FMEA, comprising the following steps:

[0037] S1: Based on the MBSE methodology, establish an MBSE model for the communication system as the model foundation for system fault analysis.

[0038] like Figure 2 As shown, the method for establishing the MBSE model of the communication system in step S1 of this embodiment is as follows: The system is modeled using the MBSE method, which is divided into three modeling levels vertically and three modeling aspects horizontally. Specifically, the modeling is divided into three levels: logical subsystem level, component level, and interface level. The communication system is modeled from top to bottom from the three aspects of system structure, function, and parameters. The logical subsystem level, component level, and interface level are respectively used as the first design level, the second design level, and the third design level from top to bottom.

[0039] like Figure 3As shown, at the logical subsystem level, the system is divided into three logical subsystems: access network, bearer network, and core network. At the component level, these logical subsystems are further decomposed into specific network elements. For example, the access network is divided into UE (User Equipment) and gNB (Ground Number Network). At the interface level, interfaces are added to the components, and these interfaces are divided into several protocol layers so that each component can communicate through the interface in a prescribed manner. For example, the gNB has a Uu-C interface, through which the gNB communicates with the UE to transmit control information. This interface contains five protocol layers: RRC, PDCP, RLC, MAC, and PHY.

[0040] Next, the functions of the communication system are modeled, taking the connected-state mobility management function as an example. At the logical subsystem level, an activity diagram for the connected-state mobility management function is established, covering measurement reporting, terminal location reporting, intra-frequency handover, and inter-frequency handover function blocks. At the component level, this embodiment uses the measurement reporting function block as an example to establish a sequence diagram for measurement reporting. At the interface level, this embodiment uses the Uu-C interface on the UE side to transmit data as an example to establish an activity diagram for data transmission via this interface.

[0041] Finally, the parameters of the communication system are modeled, such as... Figure 4 The figure shows the parameter model of the MBSE model for a communication system. Several service indicators of the system are decomposed layer by layer from top to bottom, successively through the logical subsystem level, component level, and interface level, and finally implemented as service indicators at the protocol layer.

[0042] S2: Based on the system's MBSE model, the FTA method is used to establish a functional fault tree, identify the hierarchical relationships between system functional blocks, and perform fault analysis.

[0043] This embodiment takes the connected-mode mobility management function block as an example. Connected-mode mobility management ensures that user equipment can maintain stable network connectivity and high-quality service during movement by coordinating base station handover, measuring and reporting signal quality, configuring mobility policies, and handling handover failures.

[0044] like Figure 5 The diagram shows the functional fault tree for connected mobility management. First, an FMEA item for the connected mobility management function is established, namely... Figure 5 The F-29 connected-mode mobility management failed. This function is decomposed at the component level into four functional blocks: measurement reporting, terminal location reporting, inter-frequency handover, and intra-frequency handover. Subsequently, the functional blocks at the component level are further decomposed at the interface level into functional blocks for various interfaces, and the functional blocks of the interfaces are further refined into functional blocks at the protocol layer.

[0045] When a fault occurs in the connected mobility management function block, it can be traced back using a fault tree. For example, it can be traced back to a failure in the measurement reporting function at the component level, and further back to a failure in the interface protocol layer function at the interface level. In this way, the cause of the fault can be analyzed layer by layer, ensuring the comprehensiveness and accuracy of the fault analysis.

[0046] S3: Based on the functional fault tree, use the FMEA method to analyze the important functional blocks at each level, and generate corresponding FMEA analysis tables for each level, specifically:

[0047] 1) Based on the functional fault tree and the MBSE model of the system, this embodiment takes the connected mobility management function block as the analysis object and uses the FMEA analysis method to perform FMEA analysis on the function block of the first design level (logic subsystem level) to form an FMEA analysis table;

[0048] This embodiment uses the FMEA item "connected-state mobility management failure," i.e., the faulty function block, as an example for FMEA analysis. For example... Figure 6 The table shown is the FMEA analysis table for the Connected Mobility Management functional block. The FMEA analysis items include current-level behavior, failure mode, failure cause, next-level behavior, impact of upper-level failure, upper-level behavior, final failure impact, severity, probability of occurrence, risk index, and design improvement measures. It can be seen that the level behavior for this FMEA item is "Connected Mobility Management." The failure mode is a top-level functional failure. Failure causes may include excessive load, configuration errors, software problems, network failures, and hardware failures. The next-level functional blocks include terminal location reporting, measurement reporting, inter-frequency handover, and intra-frequency handover. The impact of an upper-level failure is the inability to perform connected mobility management. The upper-level functional block is mobility management. The final failure impact is data transmission interruption or quality degradation. OCC is 1 (failure occurrence frequency; a higher value indicates a higher frequency). SEV is 2 (failure impact severity; a higher value indicates a higher severity). Design improvement measures include strengthening location management and updates, applying fault tolerance and redundancy mechanisms, optimizing network topology, and enhancing signaling coverage and quality.

[0049] The FMEA analysis table for this functional block provides a comprehensive analytical framework by listing in detail the modes, causes, effects, and control measures of connectivity mobility management failures, which helps to identify and address potential system failures.

[0050] 2) After completing the FMEA analysis at the logic subsystem level, this embodiment takes the measurement reporting function block as the analysis object. Combining the functional fault tree, MBSE model and the FMEA analysis results at the logic subsystem level, the FMEA analysis method is used to perform FMEA analysis on the function blocks at the second design level (component level) to form the corresponding FMEA analysis table.

[0051] This embodiment uses the measurement reporting function block, the next level function block in connected mobility management, as an example. The FMEA analysis tables for component-level function blocks differ from those for logic subsystem-level function blocks because the level of refinement in the system's structure, functions, and parameters varies at different design levels. The lower the level, the smaller the design granularity, the more detailed the design, and the more accurate the system description. Therefore, compared to the FMEA analysis tables for logic subsystem-level function blocks, the FMEA analysis tables for component-level function blocks are more detailed and provide more accurate fault analysis.

[0052] For example Figure 7 The table shown is the FMEA analysis table for the measurement reporting function block. According to the FMEA analysis table, the failure mode of the measurement reporting function is network element function failure. The network elements carrying this function block are UE and gNB, and the corresponding physical entities are broadband terminal, ka user payload, and integrated processing payload. The failure mode is network element function failure. The causes of failure may include configuration errors, software problems, network failures, etc. The next layer function block is several interface data transmission and reception behaviors, and the corresponding interfaces are Uu-C interface (gNB) and Uu-C interface (UE). The impact of the upper-level failure is network element communication failure. The next layer function block is connected-state mobility management. The final failure impact is the inability to provide mobility management. OCC is 1, SEV is 2. Design improvement measures include adding fault tolerance and redundancy mechanisms, enhancing protocol layer reliability, and improving the network environment.

[0053] This hierarchical FMEA analysis table for functional blocks is detailed and systematic. It displays functional blocks at different levels of the system through hierarchical decomposition, from network elements to interfaces and then to physical entities, ensuring comprehensive fault analysis. It combines system structure and function to accurately locate the source of faults and trace them back to specific physical entities. The table provides a comprehensive fault impact analysis, clarifying design improvement measures for each fault mode, such as adding fault tolerance and redundancy mechanisms, enhancing protocol layer reliability, and improving the network environment. By assessing the probability of fault occurrence and the severity of its impact, this table helps identify high-risk areas, prioritize their handling, and improve system reliability and stability.

[0054] 3) Following the component-level analysis, based on the functional fault tree, MBSE model, and FMEA analysis results at the component level, the data transmission function block of the Uu-C interface (UE side) is used as the analysis object. FMEA analysis is then performed on the function blocks at the third design level (interface level) to generate the corresponding FMEA analysis table:

[0055] This embodiment takes the Uu-C interface (UE side) data transmission function block, which is the next level of function block in the measurement reporting process, as an example. The FMEA analysis items for interface-level function blocks and component-level function blocks differ. The interface level is the lowest level of the design level, with the highest degree of design refinement, providing a more detailed and precise description of the system's parameters, and grounding the system's service indicators in specific measurable and calculable protocol layer metrics. The component-level FMEA analysis table, in addition to adding system structure information, adds specific protocol layer metrics to facilitate parameter-based fault analysis.

[0056] like Figure 8 The table shown is the FMEA analysis table for the data transmission function block of the Uu-C interface (UE side). According to the FMEA analysis table, the interface carried by this function block is the Uu-C interface (UE), and the corresponding physical entity is the broadband terminal. The fault mode is interface fault, and the causes may include incorrect destination address, configuration error, software problem, or hardware failure. The next level of function blocks are the data transmission and reception behaviors of several protocol layers of the interface. Protocol layer data transmission and reception can be further decomposed into specific protocol layer function blocks. The specific indicators of the protocol layers contained in the interface function blocks include PHY receiver algorithm, PHY communication system, RRC layer data transmission and reception latency, etc. By analyzing these specific protocol layer indicators, faults can be located more accurately for quick fault resolution. The impact of the upper-level fault is interface communication failure. The upper-level function blocks include PDU session establishment, release, modification, connection establishment, etc. The final fault impact is network element function failure, with OCC at 3 and SEV at 4. Design improvement measures include software optimization and protocol layer improvement.

[0057] The advantage of the FMEA analysis table for this functional block level lies in its detail and accuracy. By refining fault analysis to the interface level, the system's service indicators and parameters are clarified, leading to more precise fault location. The table not only adds system structure information but also specific indicators for the protocol layer, facilitating parametric fault analysis. Through the analysis of specific indicators such as PHY receiver algorithms, PHY communication systems, and RRC layer data transmission and reception delays, once functional faults are defined to specific indicators, more accurate fault-solving measures can be proposed. The correlation analysis between higher and lower levels further enhances the comprehensiveness and systematic nature of fault analysis. Risk assessment indicators (OCC, SEV) and design improvement measures (such as software optimization and protocol layer improvements) provide clear guidance for system maintenance and optimization, contributing to improved system reliability and performance.

[0058] S4: Combine the integrated functional fault tree and FMEA analysis tables of each functional block level to establish a functional fault database for the communication system, and finally generate a system fault analysis report:

[0059] FMEA analysis is performed on all important functional blocks across three design levels to create FMEA tables. Then, a functional fault database is established using a functional fault tree. Based on the MBSE model, a communication system fault database is constructed, and fault analysis reports are generated. This step ensures that functional blocks at each level are analyzed and recorded in detail, forming a comprehensive fault management database that provides a solid foundation for system maintenance and optimization.

Claims

1. A fault analysis method for communication systems based on FTA and FMEA, characterized in that, Includes the following steps: S1: Based on the MBSE methodology, establish an MBSE model for the communication system as the model basis for system fault analysis; S2: Based on the MBSE model of the system, the FTA method is used to establish a functional fault tree, identify the hierarchical relationship between system functional blocks and perform fault analysis. S3: Based on the functional fault tree, use the FMEA method to analyze the important functional blocks at each level and generate the corresponding FMEA analysis table for each level; S4: Combine the integrated functional fault tree and FMEA analysis tables of each level of functional blocks to establish a functional fault database for the communication system, and finally generate a fault analysis report for the system. The method for establishing the MBSE model of the communication system in step S1 is as follows: The MBSE method is used to model the system, and the modeling is divided into three levels: logical subsystem level, component level and interface level. The communication system is modeled from top to bottom from the three aspects of system structure, function and parameters. The logical subsystem level, component level and interface level are respectively regarded as the first design level, the second design level and the third design level from top to bottom. The specific method for establishing the functional fault tree in step S2 is as follows: Select the logical subsystem level functional blocks in the MBSE model as the fault analysis objects and establish the functional fault tree.

2. The communication system fault analysis method based on FTA and FMEA according to claim 1, characterized in that, Step S3 specifically includes: A1: Based on the functional fault tree and the MBSE model of the system, the connected mobility management functional block is used as the analysis object. The FMEA analysis method is used to perform FMEA analysis on the functional block of the first design level and form an FMEA analysis table. A2: Taking the measurement reporting function block as the analysis object, and combining the functional fault tree, MBSE model and FMEA analysis results of the logic subsystem level, the FMEA analysis method is used to perform FMEA analysis on the function block of the second design level, and form the corresponding FMEA analysis table. A3: Based on the functional fault tree, MBSE model and component-level FMEA analysis results, taking the Uu-C interface data transmission function block as the analysis object, the FMEA analysis method is used to perform FMEA analysis on the function block at the third design level, and the corresponding FMEA analysis table is formed.

3. The communication system fault analysis method based on FTA and FMEA according to claim 2, characterized in that, In the FMEA analysis table of step A1, the FMEA items include FMEA ID, FMEA name, current level behavior, failure mode, failure cause, next level behavior, upper level failure impact, previous level behavior, final failure impact, OCC, SEV, and design improvement measures.

4. The communication system fault analysis method based on FTA and FMEA according to claim 2, characterized in that, In the FMEA analysis table of step A2, the FMEA items include FMEA ID, FMEA name, current level behavior, network element, physical entity, fault mode, fault cause, next level behavior, interface, upper level fault impact, upper level behavior, final fault impact, OCC, SEV, and design improvement measures.

5. The communication system fault analysis method based on FTA and FMEA according to claim 2, characterized in that, In the FMEA analysis table of step A3, the FMEA items include FMEA ID, FMEA name, current level behavior, interface, physical entity, failure mode, failure cause, next level behavior, specific behavior of the protocol layer, protocol layer indicators, impact of upper level failure, behavior of the previous level, impact of final failure, OCC, SEV, and design improvement measures.

6. The communication system fault analysis method based on FTA and FMEA according to claim 1, characterized in that, In step S2, a functional fault tree for connected mobility management is established. The method for establishing the tree is as follows: an FMEA item for the connected mobility management function is established. This function is decomposed into four functional blocks at the component level: measurement reporting, terminal location reporting, inter-frequency handover, and intra-frequency handover. Subsequently, the functional blocks at the component level are further decomposed into functional blocks of various interfaces at the interface level, and the functional blocks of the interfaces are further refined into functional blocks of the protocol layer.

7. The communication system fault analysis method based on FTA and FMEA according to claim 1, characterized in that, Step S1 involves modeling the communication system from top to bottom, considering its structure, function, and parameters. Specifically, this includes: B1: Model the structure of the communication system. At the logical subsystem level, the system is divided into three logical subsystems: access network, bearer network, and core network. At the component level, these logical subsystems are further decomposed into specific network elements. At the interface level, interfaces are added to the components, and the interfaces are divided into several protocol layers so that each component can communicate through the interface in a specified manner. B2: The functions of the communication system are modeled. At the logical subsystem level, an activity diagram of the connection-state mobility management function is established, covering the function blocks of measurement reporting, terminal location reporting, intra-frequency handover, and inter-frequency handover. At the component level, taking the measurement reporting function block as an example, a sequence diagram of measurement reporting is established. At the interface level, taking the Uu-C interface on the UE side as an example, an activity diagram of the interface for sending data is established. B3: The parameters of the communication system are modeled, and the system's service indicators are decomposed layer by layer from top to bottom, passing through the logical subsystem level, component level and interface level in turn, and finally implemented as service indicators at the protocol layer.

Images