Highly Accurate Clock Synchronization With Drift Correction for the Controller Area Network


Akpinar M., Schmidt E. G. , Schmidt K. W.

IEEE TRANSACTIONS ON PARALLEL AND DISTRIBUTED SYSTEMS, vol.33, no.12, pp.4071-4082, 2022 (Peer-Reviewed Journal) identifier identifier

  • Publication Type: Article / Article
  • Volume: 33 Issue: 12
  • Publication Date: 2022
  • Doi Number: 10.1109/tpds.2022.3179316
  • Journal Name: IEEE TRANSACTIONS ON PARALLEL AND DISTRIBUTED SYSTEMS
  • Journal Indexes: Science Citation Index Expanded, Scopus, Academic Search Premier, Aerospace Database, Applied Science & Technology Source, Business Source Elite, Business Source Premier, Communication Abstracts, Compendex, Computer & Applied Sciences, INSPEC, Metadex, Civil Engineering Abstracts
  • Page Numbers: pp.4071-4082
  • Keywords: Controller area network, clock synchronization, offset correction, drift correction, phase error, TIME SYNCHRONIZATION, FAULT-TOLERANT

Abstract

Modem vehicles, that have to be considered as safety-critical cyber-physical systems, require highly accurate clock synchronization (CS) among their distributed computing devices. Since Controller Area Network (CAN) is the predominant in-vehicle communication bus, it is highly relevant to support CS for CAN. This article proposes an original CS method for distributed in-vehicle networks based on CAN with both offset and drift correction. While offset correction is performed based on timestamps in periodic reference messages (RMs), our new method benefits from the re-synchronization mechanism of the CAN bit timing to apply highly accurate drift correction. Our algorithm does not make any modifications to the CAN protocol but requires the measurement of the phase error from the CAN controller. We derive analytical bounds for the expected clock differences and further validate the practicability of the proposed method by comprehensive experiments. As the main result, our method achieves a clock accuracy below 2 mu s independent of important parameters such as the bit rate, RM period, bus utilization and time-varying clock drifts.