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Recursive Time Synchronization Method Based on GPIO Signal Delay Compensation and EMA Filter

GPIO EMA 신호 지연 보상 및 필터 기반 재귀적 시간 동기화 기법

  • Received : 2019.10.28
  • Accepted : 2019.11.29
  • Published : 2020.02.29

Abstract

We propose a system time synchronization method between embedded Linux-based distributed control devices by using Transmission Control Protocol (TCP) communication and General Purpose Input Output (GPIO) device. The GPIO signal is used as the trigger signal for synchronization and the TCP communication is used to transfer the system time of master Linux, which serves as the reference clock, to slave Linux. Precise synchronization performance is achieved by measuring and compensating for the propagation delay of GPIO signal and the acquisition and setting latency of Linux system time. We build an experimental setup consisting of two embedded Linux systems, and perform extensive experiments to verify the performance of the proposed synchronization method.

Keywords

References

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