Integrated radio frequency system model based on meta-model and integrated radio frequency system design method

Abstract

The invention belongs to the field of integrated radio frequency systems, and particularly relates to a meta-model-based integrated radio frequency system model and an integrated radio frequency system design method, and the system model comprises a conceptual model, a logic model and a data model; the conceptual model comprises a use case model and a composition model; the use case model is used for describing a top layer operation framework and a system boundary of the system and is described by adopting a use case graph of a SysML language; the composition model is used for describing the concept composition relation of the system, and a block definition graph of SySML language is adopted for description; the logic model comprises activities and interfaces; the activity is a basic element for describing system behaviors and is described by adopting an SysML language activity graph; the interface is a basic element for describing external transmission elements of elements in different forms, and is described by adopting an SysML language internal block diagram; the data model comprises system form elements and physical data; system form elements are basic elements for instantiating a system concept and are described by adopting a SysML language block definition graph; physical data is a basic element for describing interaction between systems and is described by adopting a SysML language internal block diagram.

Description

Technical Field

[0001] The present invention belongs to the field of integrated radio frequency systems, and in particular relates to an integrated radio frequency system model based on a meta-model and an integrated radio frequency system design method. Background Art

[0002] The metamodel is a model of the model. Using the metamodel to build the system architecture can solve the problem of product data consistency. Usually the metamodel is based on the classic metadata architecture. The four-layer metamodel is the UML language architecture developed by the OMG organization. Among them:

[0003] Information layer: Information layer is composed of the data we want to describe, which is usually some user data. Its main responsibility is to describe the detailed information of the information field.

[0004] Model layer: The model is composed of metadata. Metadata is data that describes the information layer. The collection of metadata is called a model.

[0005] The main responsibility of the model is to define an "abstract language" to describe the information layer. The data of the information layer, that is, user data, is an instance of the model layer.

[0006] Metamodel layer: The metamodel layer is composed of meta-metadata. Meta-metadata defines the structure and semantics of metadata. The collection of meta-metadata is called a metamodel.

[0007] The main functions of airborne RF systems include different electromagnetic functions such as reconnaissance, interference, exploration, and communication. With the improvement of the integration level of equipment, general resource reuse has become difficult to achieve a leapfrog improvement in system design. The integrated RF system requires breaking the independence of different functions, and gradually coupling each function at the signal level, information level, and resource reuse level to achieve the overall optimization of the system. However, the coupling of functions has subverted the previous linear design process of integrated RF system functions through aperture processing-RF processing-signal processing-information processing, greatly increasing the difficulty of system design. Summary of the invention

[0008] The purpose of the present invention is to propose a meta-model-based integrated RF system model and an integrated RF system design method, to realize the system architecture design of an integrated integrated RF system, to carry out system architecture characterization research based on the meta-model for airborne RF functions, to realize the meta-model description and data model design of tasks, functions, physical resources, etc. in the electromagnetic dimension, to realize the definition of the logic and interface relationship of system tasks, functions, and physical resources, and to establish a corresponding digital architecture model.

[0009] The technical solution of the present invention:

[0010] A comprehensive radio frequency system model based on a meta-model, including: a conceptual model, a logical model and a data model;

[0011] The conceptual model includes the use case model and the composition model. The use case model is used to describe the top-level operating architecture and system boundaries of the system, and is described using the use case diagram of the SysML language. The composition model is used to describe the conceptual composition relationship of the system, and is described using the block definition diagram of the SysML language.

[0012] The logical model includes activities and interfaces. Activities are the basic elements for describing system behaviors and are described using SysML language activity diagrams. Interfaces are the basic elements for describing the external transmission of elements in different forms and are described using SysML language internal block diagrams.

[0013] The data model includes system formal elements and physical data; system formal elements are the basic elements for instantiating system concepts and are described using SysML language block definition diagrams; physical data are the basic elements for describing interactions between systems and are described using SysML language internal block diagrams.

[0014] Furthermore, the use case model of the integrated RF system includes five first-level use cases: reconnaissance, interference, detection, communication, and management;

[0015] Among them, reconnaissance includes three secondary use cases: passive positioning, passive detection, and radar warning;

[0016] Interference includes two secondary use cases: active interference and passive interference;

[0017] Detection includes four secondary use cases: radar detection, infrared detection, photoelectric detection, and collaborative detection within the platform;

[0018] Communications include five secondary use cases: data link communications, voice communications, navigation, identification, and elastic networking;

[0019] Management includes three secondary use cases: system management, sensor management, and task management.

[0020] Furthermore, the composition model of the integrated RF system includes: a first-level skin integrated processing system and a second-level integrated processing system, wherein the first-level skin integrated processing system includes a skin front-end unit, a RF unit, and a RF signal preprocessing unit, and the second-level integrated processing system includes a network switching unit, a logic processing unit, and a heterogeneous computing unit.

[0021] Furthermore, activities include multiple element types such as basic actions, object flows, control flows, plugs, decision nodes, merge nodes, branch nodes, collection nodes, and call behaviors.

[0022] Furthermore, the interface includes: a standard interface and a flow interface; the standard interface is used to characterize the signal and information triggered interaction of the integrated radio frequency system, and the flow interface is used to characterize the system power supply continuous interaction.

[0023] Furthermore, the formal elements include: a first-level skin integrated processing system, a second-level integrated processing system skin front-end unit, a radio frequency unit, a radio frequency signal preprocessing unit, a network switching unit, a logic processing unit, and a heterogeneous computing unit, which are basic elements for instantiating the system concept.

[0024] Physical data includes: system waveform parameter table, pulse description words, communication signal format and formatted data for system interaction.

[0025] A meta-model-based integrated radio frequency system design method is implemented based on the integrated radio frequency system model, comprising the following steps:

[0026] Step 1: Conduct demand analysis, extract the use cases of the system, and apply the use case model in the use case diagram to build the corresponding system functional framework according to the corresponding use cases;

[0027] Step 2: Perform functional analysis to convert system requirements generated by requirement analysis into activities. Driven by use cases, each secondary use case will be analyzed and an executable state machine model will be generated. The state machine model will be self-verified by execution.

[0028] Step 3: Perform physical analysis. By dividing the system architecture, allocate the activities generated in step 2 to the formal elements in the system architecture, thereby realizing port / interface allocation, attribute / parameter allocation, and refining the physical data during the allocation process.

[0029] Further, in step one, the specific process is as follows:

[0030] 1) Analyze and decompose the accepted user requirements, transform them into understandable, designable and unambiguous system requirements, and link the system requirements to the user requirements to ensure that all user requirements can be traced;

[0031] 2) Define system use cases based on user requirements and OpsCon, preliminarily set external participants of system use cases according to the operational concept, and <association>Relationships are associated with corresponding use cases;

[0032] 3) Establish system requirements and system use cases <trace>Related relationships;

[0033] 4) Establish the relationship between use cases, set up two levels according to the complexity of the system, and use use cases at different levels <contain>Relationship association, the upper-level use case includes the lower-level use case.

[0034] Further, in step 2, the specific process is as follows:

[0035] 1) Through detailed analysis of specific use cases, sort out the general operating scenarios of the functions described in the use cases, refine and supplement the use cases involving external participants and the interaction behaviors with the participants, and define the operating scenarios of the system under the use cases;

[0036] 2) Build the functional flow of the system through activities according to the use case operation logic, and describe the operation process of the system through SysML activity diagram;

[0037] 3) In the activity diagram, define the external ports and internal ports for the functional flows of the system's external interactions and the system's cross-lane interactions, and define the port type as a standard port or a flow port according to the form of the interaction content; define the corresponding interface in the port according to the interaction content definition by calling the interface metamodel;

[0038] 4) Define the use case runtime in the normal operation scenario according to the activity diagram and port and interface definitions, and describe them uniformly in the SysML timing diagram;

[0039] 5) Through model execution, the running results of the running sequence and running interface are compared with the model constraint results to verify that the modeling logic is feasible and achievable.

[0040] Furthermore, in step three, the specific process is as follows: define the use case context and define the use case scenario, through detailed analysis of the specific use case, sort out the general operating scenarios of the functions described in the use case, refine and supplement the use cases involving external participants and the interaction behaviors with the participants, and define the operating scenarios of the system under the use case.

[0041] Beneficial effects of the present invention:

[0042] The system architecture design of integrated RF systems in different fields can be carried out based on the present invention. The model elements suitable for this field can be defined through the model description in the present invention. The system architecture model of the integrated RF system can be constructed through the method of the present invention, thereby improving design efficiency and unifying system cognition. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 compose definition diagrams for system architecture models;

[0044] Figure 2 This is a schematic diagram of the system interference use case model;

[0045] Figure 3 This is a schematic diagram of the system composition model;

[0046] Figure 4 It is a schematic diagram of the clock calibration and FC processing activity model;

[0047] Figure 5 It is a schematic diagram of the interface model;

[0048] Figure 6 It is a schematic diagram of the formal element model;

[0049] Figure 7 It is a schematic diagram of the physical data model of the pulse description word;

[0050] Figure 8 Provide a flow chart for the requirements analysis process;

[0051] Fig. 9 Flowchart for functional analysis process;

[0052] Fig.10 It is a flow chart of the physical analysis process;

[0053] Fig.11 Navigate use case diagrams for integrated RF systems;

[0054] Fig.12 It is the ADF requirement diagram of the integrated RF system;

[0055] Fig.13 It is the ADF activity diagram of the integrated RF system;

[0056] Fig.14 Interface diagram for ADF use case and pilot;

[0057] Fig.15 It is the ADF timing diagram of the integrated RF system;

[0058] Fig.16 Provides an architecture diagram for the integrated RF system;

[0059] Fig.17 Assign activity diagrams to ADF use cases;

[0060] Fig.18 It is the IBD diagram of the integrated radio frequency system;

[0061] Fig.19 Assignment diagram of integrated RF system port interfaces for ADF functions;

[0062] Fig. 20 This is the state machine diagram for the ADF use case. DETAILED DESCRIPTION

[0063] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0064] The present invention provides a meta-model definition for system architecture design, and realizes the construction of an architecture model of an integrated comprehensive radio frequency system based on the meta-model.

[0065] The present invention mainly includes data partitioning of system architecture, metamodel definition and original model examples in an integrated comprehensive radio frequency system.

[0066] The technical solution of the present invention is:

[0067] An architectural data partitioning oriented to system element objects. A system is a collection of elements and the relationships between them. As a description of the system, the system architecture should include the following descriptions:

[0068] The top-level organizational concept of the system, including behavioral components and element components

[0069] The organization of a system consists of the structural elements of the system and the interfaces between them and the behaviors exhibited when these elements work together.

[0070] How to organize these elements so that they are gradually integrated into better subsystems.

[0071] According to the system architecture data requirements, the system architecture model is divided into conceptual model, logical model, and data model. The conceptual model includes the use case model and component model, the logical model includes activities and interfaces, and the data model includes system form elements and physical data. Figure 1 Shown

[0072] 1. Metamodel definition

[0073] 1) Use Case Model

[0074] The use case model is used to describe the top-level operating architecture and system boundaries of the system. It is described using the use case diagram of the SysML language. The integrated comprehensive RF system use case model is as follows: Figure 2 shown.

[0075] The use case diagram for a comprehensive RF system includes:

[0076] 2) Composition model

[0077] The composition model is used to describe the conceptual composition relationship of the system. It is described using the block definition diagram of the SySML language. The composition model of the integrated comprehensive RF system is as follows: Figure 3 shown.

[0078] The block definition diagram of the integrated RF system includes: a first-level (skin) integrated processing system and a second-level integrated processing system, wherein the first-level (skin) integrated processing system includes a skin front-end unit, a RF unit, and a RF signal preprocessing unit, and the second-level integrated processing system includes a network switching unit, a logic processing unit, and a heterogeneous computing unit.

[0079] 3) Activities

[0080] Activities are the basic elements for describing system behaviors, including basic actions, object flows, control flows, plugs, decision nodes, merge nodes, branch nodes, collection nodes, and call behaviors. They are described using SysML language activity diagrams. The integrated RF system activity elements are as follows: Figure 4 Shown

[0081] 4) Interface

[0082] Interface is the basic element that describes the elements transmitted to the outside in different forms, including standard interface and flow interface, which is described by SysML language internal block diagram. The interface elements of integrated comprehensive RF system are as follows: Figure 5 Shown

[0083] 5) Formal elements

[0084] System formal elements are the basic elements for instantiating system concepts, including system components, which are described using SysML language block definition diagrams. The formal elements of an integrated comprehensive RF system are as follows: Figure 6 Shown

[0085] 6) Physical data

[0086] Physical data is the basic element for describing the interaction between systems. It is described using SysML block definition diagrams. Integrated comprehensive RF physical data such as Figure 7 Shown

[0087] This method builds the system architecture of the comprehensive RF system in accordance with the R (requirements)-F (functions)-L (logic)-P (physical) framework of system engineering. Through the model-based system design process, it is an iterative process of loop -> feedback -> iteration. Especially in the use case analysis process, it is necessary to consider the situation when a project has a large number of use cases. At this time, the development process has not changed, but the engineering architecture has changed. The new engineering structure supports team collaboration. Each use case can be carefully divided into multiple parts and then merged into a system model. The entire architecture modeling process is logically divided into three processes: requirements analysis, functional analysis, and physical analysis.

[0088] 1. Requirements Analysis Process

[0089] The main goal of the requirements analysis process is to refine the top-level operating concepts of the system. By analyzing the requirements, the atomic functions of the system are extracted. According to the corresponding atomic functions, the use case model is used in the use case diagram to build the corresponding system functional framework and describe the system boundaries. The specific analysis process is as follows: Figure 8 Shown

[0090] Requirements analysis process flow:

[0091] 1) Analyze / refine system requirements, analyze and decompose the accepted user requirements, transform user requirements into understandable, designable, and unambiguous system requirements, and link system requirements to user requirements to ensure that all user requirements are traceable.

[0092] 2) Define system use cases. Define system use cases based on user requirements and OpsCon (operation concept). Preliminarily set external participants for system use cases based on the operation concept and <association>Relationships are associated with corresponding use cases.

[0093] 3) Link functional / performance requirements to system use cases, and establish functional / performance requirements of system requirements with system use cases <trace>Associative relationship.

[0094] 4) Organize the system use cases, establish the relationship between the use cases, set up two levels according to the complexity of the system, and use the use cases at different levels. <contain>Relationship association, the upper-level use case includes the lower-level use case.

[0095] 2. Functional analysis process

[0096] The main goal of the system function analysis process is to transform the functional system requirements generated in the requirements analysis phase into a more accurate system description. This process is use case driven. Each underlying use case will be analyzed and an executable model will be generated. The model will be self-verified by execution. Fig. 9 shown.

[0097] Functional analysis process flow:

[0098] 1) Define the use case context and use case scenarios. Through detailed analysis of specific use cases, sort out the general operating scenarios of the functions described in the use cases, refine and supplement the use cases involving external participants and the interaction behaviors with the participants, and define the operating scenarios of the system under the use case.

[0099] 2) Call the metamodel to build the functional flow according to the use case scenario, build the system's functional flow by calling the logical metamodel according to the use case operation logic, and describe the system's operation process through SysML activity diagram.

[0100] 3) Define ports and interfaces. Define external ports and internal ports for the functional flows of external interactions and cross-lane interactions within the system in the activity diagram. Define the port type as a standard port or a flow port according to the form of the interaction content. Define the corresponding interface in the port by calling the interface metamodel according to the interaction content definition.

[0101] 4) Define the use case runtime timing. According to the activity diagram and port and interface definitions, define the use case runtime timing under the normal operation scenario and describe it uniformly in the SysML timing diagram.

[0102] 5) Verify the use case model through model execution. Through model execution, compare the running results of the running sequence and running interface with the model constraint results to verify that the modeling logic is feasible and achievable.

[0103] 3. Physical analysis process

[0104] The goal of the physical analysis process is to develop the physical architecture of the system. The architecture needs to meet the performance requirements and ensure the realization of the system functional requirements. The physical analysis process implements the development and design of the physical architecture by dividing the system architecture, allocating ports / interfaces, and allocating attributes / parameters, and verifying the integrity of the model requirements. The specific process is as follows: Fig.10 Shown

[0105] Physical analysis process flow:

[0106] 1) Define the use case context and use case scenarios. Through detailed analysis of specific use cases, sort out the general operating scenarios of the functions described in the use cases, refine and supplement the use cases involving external participants and the interaction behaviors with the participants, and define the operating scenarios of the system under the use case.

[0107] Example

[0108] Since the integrated RF system has many functions, but the architecture design process of each function is similar, compass navigation is used as an example to demonstrate the design process based on the meta-model. The system architecture design of other functions is similar.

[0109] 1. Requirements Analysis Process

[0110] 1) Use case division and definition

[0111] In this case, compass navigation belongs to the radio navigation function of integrated radio frequency. Based on the functional boundary of the radio navigation function of the airborne integrated radio frequency system, the system use case of the radio navigation function set is defined, the system boundary and system context interaction are preliminarily identified, and the navigation use case is preliminarily defined by decomposing / combining use cases and establishing the connection relationship of the system context. The airborne radio navigation function can be divided into ground proximity warning, radio altitude, radio compass, TACAN, satellite, pointing beacon, instrument landing, microwave landing, precision ranging and other functions according to the function. The functions are decoupled from each other, so the use cases are divided according to the relevant functions, such as Fig.11 shown.

[0112] 2) Link requirements to system use cases

[0113] Extract the functional performance requirements related to ADF functions and compare these requirements with system use cases. <trace>Related, such as Fig.12 shown.

[0114] 2. Functional analysis process

[0115] 1) Use case functional decomposition

[0116] Decompose the system operation process for the ADF use case, analyze the specific activities that the integrated RF system needs to perform when executing the ADF function, and identify the interaction with the system context during the execution of these activities, such as Fig.13 shown.

[0117] 2) Define the system port interface

[0118] According to the division of the ADF functional activity diagram, sort out the interactive ports and interfaces with the system context during activity execution, and establish external and internal interfaces in the interactive ports according to the event type. Fig.14 shown.

[0119] 3) Define the timing of use case allocation

[0120] According to the activity diagram process, sort out the timing distribution of system operation, define the operation sequence of internal and external interactions and activities in the system, express it in the form of lifeline, use tools to simulate the activity diagram, compare it with the timing distribution of its own operation, and verify the operation logic of the system. Fig.15 shown.

[0121] 1. Physical analysis process.

[0122] 1) System architecture design

[0123] The system architecture is decomposed according to the logical architecture of the system. In this case, the aircraft system is decomposed into several parts: aircraft structure, power system, cockpit system, flight management system, mission system, radio frequency system, and weapon system.

[0124] 2) System allocation design

[0125] According to the above system allocation, the system activities are allocated to different parts of the system.

[0126] 3) Port interface allocation design

[0127] According to the activity allocation results, the system ports and interfaces are sorted and allocated. The comprehensive RF system allocation results are as follows: Fig.19 As shown:

[0128] 4) State machine design and logic self-verification design

[0129] According to the above design elements, the system state machine design is carried out, and the integrated RF system state machine is as follows: Fig. 20 As shown, the state machine is run to verify the system design logic.

[0130] The above is only a specific embodiment of the present invention, and the present invention is described in detail. The unexplained part is a conventional technology. However, the protection scope of the present invention is not limited to this. Any changes or substitutions that can be easily thought of by any technician familiar with the technical field within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. The protection scope of the present invention shall be based on the protection scope of the claims.< / trace> < / contain> < / trace> < / association> < / contain> < / trace> < / association>

Claims

1. A comprehensive RF system model based on a meta-model, characterized by: The system model includes: a conceptual model, a logical model and a data model; The conceptual model includes the use case model and the composition model. The use case model is used to describe the top-level operating architecture and system boundaries of the system, and is described using the use case diagram of the SysML language. The composition model is used to describe the conceptual composition relationship of the system, and is described using the block definition diagram of the SysML language. The logical model includes activities and interfaces. Activities are the basic elements for describing system behaviors, and are described using SysML language activity diagrams. Interfaces are the basic elements for describing the external transmission of elements in different forms, and are described using SysML language internal block diagrams. The data model includes system formal elements and physical data; system formal elements are the basic elements for instantiating system concepts and are described using SysML language block definition diagrams; physical data are the basic elements for describing interactions between systems and are described using SysML language internal block diagrams.

2. The integrated radio frequency system model according to claim 1, characterized in that: The use case model of the integrated radio frequency system includes five first-level use cases: reconnaissance, interference, detection, communication, and management; Among them, reconnaissance includes three secondary use cases: passive positioning, passive detection, and radar warning; Interference includes two secondary use cases: active interference and passive interference; Detection includes four secondary use cases: radar detection, infrared detection, photoelectric detection, and collaborative detection within the platform; Communications include five secondary use cases: data link communications, voice communications, navigation, identification, and elastic networking; Management includes three secondary use cases: system management, sensor management, and task management.

3. The integrated radio frequency system model according to claim 2, characterized in that: The composition model of the integrated RF system includes: a first-level skin integrated processing system and a second-level integrated processing system. The first-level skin integrated processing system includes a skin front-end unit, a RF unit, and a RF signal preprocessing unit. The second-level integrated processing system includes a network switching unit, a logic processing unit, and a heterogeneous computing unit.

4. The integrated radio frequency system model according to claim 3, characterized in that: Activities include basic actions, object flows, control flows, plugs, decision nodes, merge nodes, branch nodes, collection nodes, and call behaviors.

5. The integrated radio frequency system model according to claim 4, characterized in that: The interfaces include: Standard interface and stream interface; The standard interface is used to characterize the signal and information triggered interaction of the integrated RF system, and the stream interface is used to characterize the system power supply continuous interaction.

6. The integrated radio frequency system model according to claim 5, characterized in that: The formal elements include: first-level skin integrated processing system, second-level integrated processing system skin front-end unit, radio frequency unit, radio frequency signal preprocessing unit, network switching unit, logic processing unit, and heterogeneous computing unit, which are the basic elements for instantiating the system concept. Physical data includes: system waveform parameter table, pulse description words, communication signal format and formatted data for system interaction.

7. A meta-model-based integrated radio frequency system design method, implemented based on the integrated radio frequency system model of any of the preceding claims, characterized in that: The following steps are involved: Step 1: Conduct demand analysis, extract the use cases of the system, and apply the use case model in the use case diagram to build the corresponding system functional framework according to the corresponding use cases; Step 2: Perform functional analysis to convert system requirements generated by requirement analysis into activities. Driven by use cases, each secondary use case will be analyzed and an executable state machine model will be generated. The state machine model will be self-verified by execution. Step 3: Perform physical analysis. By dividing the system architecture, allocate the activities generated in step 2 to the formal elements in the system architecture, thereby realizing port / interface allocation, attribute / parameter allocation, and refining the physical data during the allocation process.

8. The method according to claim 7, characterized in that: In step one, the specific process is as follows: 1) Analyze and decompose the accepted user requirements, transform them into understandable, designable and unambiguous system requirements, and link the system requirements to the user requirements to ensure that all user requirements can be traced; 2) Define system use cases based on user requirements and OpsCon, preliminarily set external participants of system use cases according to the operational concept, and <association> Relationships are associated with corresponding use cases;< / association> 3) Establish system requirements and system use cases <trace> Related relationships;< / trace> 4) Establish the relationship between use cases, set up two levels according to the complexity of the system, and use use cases at different levels <contain> Relationship association, the upper-level use case includes the lower-level use case.< / contain> 9. The method according to claim 8, characterized in that: In step 2, the specific process is as follows: 1) Through detailed analysis of specific use cases, sort out the general operating scenarios of the functions described in the use cases, refine and supplement the use cases involving external participants and the interaction behaviors with the participants, and define the operating scenarios of the system under the use cases; 2) Build the functional flow of the system through activities according to the use case operation logic, and describe the operation process of the system through SysML activity diagram; 3) In the activity diagram, define the external ports and internal ports for the functional flows of the system's external interactions and the system's cross-lane interactions, and define the port type as a standard port or a flow port according to the form of the interaction content; define the corresponding interface in the port according to the interaction content definition by calling the interface metamodel; 4) Define the use case runtime in the normal operation scenario according to the activity diagram and port and interface definitions, and describe them uniformly in the SysML timing diagram; 5) Through model execution, the running results of the running sequence and running interface are compared with the model constraint results to verify that the modeling logic is feasible and achievable.

10. The method according to claim 9, characterized in that: In step three, the specific process is as follows: define the use case context and define the use case scenario. Through detailed analysis of the specific use case, sort out the general operating scenarios of the functions described in the use case, refine and supplement the use cases involving external participants and the interaction behaviors with the participants, and define the operating scenarios of the system under the use case.

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