Journal of Institute of Control, Robotics and Systems (제어로봇시스템학회논문지)

Institute of Control, Robotics and Systems (제어로봇시스템학회)
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Evaluation of Synchronization Performance with PTP

정밀 시각 프로토콜 동기 성능 평가

  • Lee, Young-Kyu (Division of Physical Metrology, Korea Research Institute of Science and Technology) ;
  • Yang, Sung-Hoon (Division of Physical Metrology, Korea Research Institute of Science and Technology) ;
  • Lee, Chang-Bok (Division of Physical Metrology, Korea Research Institute of Science and Technology) ;
  • Lee, Jong-Goo (Division of Physical Metrology, Korea Research Institute of Science and Technology) ;
  • Park, Young-Mi (The 2nd R&D Institute, Agency for Defense Development) ;
  • Lee, Moon-Seok (Electronic Warfare R&D Lab., LIGNex1)
  • 이영규 (한국표준과학연구원 시간센터) ;
  • 양성훈 (한국표준과학연구원 시간센터) ;
  • 이창복 (한국표준과학연구원 시간센터) ;
  • 이종구 (한국표준과학연구원 시간센터) ;
  • 박영미 (국방과학연구소 전자전 분야) ;
  • 이문석 (LIG 넥스원 전자전 연구센터)
  • Received : 2014.03.07
  • Accepted : 2014.04.04
  • Published : 2014.06.01
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Abstract

In this paper, we described the investigated theoretical time synchronization performances and experiment results obtained by commercially provided PTP (Precise Time Protocol) modules when the time of a slave clock is synchronized to the master clock. In the case of the theoretical performance analysis, we investigated 3 types of clock levels such as Crystal Oscillator (XO), TCXO (Temperature Compensated XO) and OCXO (Oven Controlled XO). From the analysis, it was observed that the synchronization performance is greatly influenced by the synchronization period and the required performance under 1 us can be achieved by using XO level clocks when the synchronization period is less than 2 seconds and the uncertainty of the propagation delay is under 100 ns. For the experiments using commercial PTP modules, the synchronization performance was investigated for direct, through 1 hub and through 2 hubs connections between the master clock and the slave clock. From the experiment results, we observed that time synchronization under 90 ns with 1,000 seconds observation interval can be achieved in the case of direct connection.

Keywords

References

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