Vehicle CAN Bus Physical Layer Simulation Base On Saber

With the development of automotive industry, passengers' safety and comfort were increasingly concerned in passenger vehicles, more and more electronic device were applied in automotive. Large numbers of data and control information are transmitted between these different electronic devices, thus automotive bus network design comes up with new challenges. Fist of all, automotive bus network topology becomes more complicated, and the length of the bus is getting longer and longer. At the same time,with the increase of automotive electronic devices, automotive electromagnetic environment has became increasingly harsh for bus network, therefore new requirements are also raised for the bus signal immunity. To solve the above problems, the mathematical modeling of physical layer was built up. And simulation analysis to implement automatic test was performed.By using Saber software, the automatic multi-node CAN bus physical layer simulation system was designed and implemented. Fistly, the technical features of Saber Software and its application in automotive industry was introduced. CAN bus physical layer simulation was modeled by using Saber software. And a vehicle CAN bus physical layer simulation model was discussed. Then the modeling method in CAN bus physical layer simulation with Saber software was discussed. The simulation model of automotive CAN bus physical layer was built up. And based on Saber AIM the automatic test management platform setup was performed to implement re-development.The precision of automotive CAN bus physical layer simulation model is directly related to the application scope of the model. In order to achieve the model precision within specified tolerance range, how to implement the model precision adjustment with manual test and simulation test data was detailedly introduced.Manual test in single node and system bench test circuit was performed by using test equipment such as oscilloscope to record the test waveforms. The test data was inputted to Saber to realize the comparision between manual test data and automatic test data. And then according to more deviated parameters the model was adjusted. By repeatedly adjusting in this way, the precision of simulation model can be hold within a specified range.Through automated simulation software, CAN bus physical layer system of a certain vehicle was simulated. And then the test bench was set up. After data comparision, the most simulation results and experimental results were basically same, but the other parts of the data were within the tolerance range. Finally the accuracy of the simulation results of test model in real vehicle was re-verified.