Timing analysis of real-time communication under electromagnetic interference

This paper discusses aspects of dependability of real-time communication. In particular, we consider timing behaviour under fault conditions for Controller Area Network (CAN) and the extension Time-triggered CAN (TTCAN) based on a time-driven schedule. We discuss the differences between these buses and their behaviour under electromagnetic interference. We present response timing analyses for CAN and TTCAN in the presence of transient network faults using a probabilistic fault model where random faults from electromagnetic interference occur. The CAN analysis provides a probability distribution of worst case response times for message frames. The results indicate that CAN may generally provide a higher probability of delivering messages on time than TTCAN. The CAN analysis result is used to discuss an approach to implementing a bus guardian for event-triggered systems.