A method for response time computation in FlexRay communication system

As a new communication protocol, FlexRay, which is supported by FlexRay Consortium consisting of many biggest automobile companies, is becoming a de-facto standard for automobile communication system. This paper provides a timing analysis of the FlexRay communication cycle, including static (ST) segment and dynamic (DYN) segment, and proposes a methodology to calculate the worst-case response time of static segment and dynamic segment respectively, taking the communication delay and all the possible factors into account. Besides, this paper presents a way to determine whether messages in DYN segment could be transmitted in the current cycle based on the some related work. Finally, a model which can be implemented in FPGA for application is created to simulate the ideal situation and the real node state; the behavior simulation result and post-route simulation result are compared and analyzed to demonstrate the preceding theory.