The Design And Implementation Of The In-Vehicle Network Simulation System And Analysis Of The Network Performance

Technical progress of in-vehicle network is closely related to the development of automotive electronic technology. With the increase of electronic control units (ECU) used in vehicle and complexity of network systems, the in-vehicle network system is facing strict safety and reliability requirements. Based on this background, the research and development of in-vehicle network is brought forward and carried out.The in-vehicle network is associated with vehicle structure and involves a wide range of aspects, so it is a complex task. To make the research work concrete and effective, the dissertation mainly researched on the establishment of in-vehicle CANbus simulation system, the analysis and test of the performance of the simulation system and the analysis of FlexRay characteristics.In this dissertation, the characteristics of CAN nodes of in-vehicle network are analyzed, and then the rapid prototyping method of network node simulation is proposed based on MATLAB/RTW. Using the method, the function and performance simulation of each network node can be effectively implemented, and the simulation node can be adjusted and configured flexibly. The method can satisfy the simulation needs of different type of information with great adaptability. Beside this, the in-vehicle network structure is analyzed, based on which the structure of simulation system and the development environment of physical layer and data link layer are obtained. On this basis, the in-vehicle CAN network simulation system is implemented. The simulation system can verify whether the network structure and application-layer protocol are feasible and reasonable, and can test and analyze the physical layer and link layer in the early design stage. Therefore, the simulation system provides a development platform for the evaluation and design of the in-vehicle network.In the design stage of in-vehicle network, a series of performance tests must be carried out to ensure the safety and reliability, and to improve the network design based on the test results. Therefore in this dissertation, a series of analysis and evaluation covering the physical layer, data link layer and application-layer are carried out on the simulation system,which provides dependence and security for the network real-time performance and reliability, and also provides basis for the network system design both on theory and methods.In the performance analysis of FlexRay protocol, its characteristics, principal functions and mechanisms of the network topology etc. are presented, meanwhile its application area and technical advantages are analyzed. Since FlexRay has a high bandwidth, high reliability, and is a deterministic communication protocol with fault tolerance, it meets the advanced control application demands of future vehicles. In this dissertation, the functions and characteristics of FlexRay protocol are analyzed, which provides full technical reserves for further development of the technology of in-vehicle network.The establishment method of in-vehicle network simulation system is proposed in this dissertation, simple analysis and tests are carried out base on the simulation system, and the performance of FlexRay is analyzed, which has certain guiding significance for the research and development of in-vehicle network system.