Enhanced utilization bound of Rate-Monotonic scheduling in Controller Area Networks

• We developed a utilization bounds of RM scheduling for CAN.
• Utilization bound is improved from 25% to 34% for CAN 2.0A.
• Utilization bound is improved from 29% to 41% for CAN 2.0B.
• Restriction: no single message stream utilization exceeds 46% for CAN 2.0A.
• Restriction: no single message stream utilization exceeds 27% for CAN 2.0B.

When priorities to message streams are assigned using Rate Monotonic (RM) for a Controller Area Network (CAN), the utilization bound is known to be about 25% for CAN 2.0A and 29% for CAN 2.0B. In this letter, we present a higher utilization bound than the existing ones with a reasonable constraint. The new utilization bounds are approximately 34% for CAN 2.0A and 41% for CAN 2.0B if no single message stream's utilization exceeds 46% or 27% of the total utilization for CAN 2.0A or CAN 2.0B, respectively.