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Design of Performance Monitoring System for eLoran Time Synchronization Service

eLoran 시각동기 성능 모니터링 시스템 설계

  • Seo, Kiyeol (Korea Research Institute of Ships & Ocean Engineering) ;
  • Son, Pyo-Woong (Korea Research Institute of Ships & Ocean Engineering) ;
  • Han, Younghoon (Korea Research Institute of Ships & Ocean Engineering) ;
  • Park, Sang-Hyun (Maritime PNT Research Office, Korea Research Institute of Ships & Ocean Engineering) ;
  • Lee, Jong-Cheol (National Maritime PNT Office, MOF)
  • 서기열 (한국해양과학기술원 부설 선박해양플랜트연구소) ;
  • 손표웅 (한국해양과학기술원 부설 선박해양플랜트연구소) ;
  • 한영훈 (한국해양과학기술원 부설 선박해양플랜트연구소) ;
  • 박상현 (한국해양과학기술원 부설 선박해양플랜트연구소 해양PNT연구단) ;
  • 이종철 (해양수산부 국립해양측위정보원)
  • Received : 2021.09.14
  • Accepted : 2021.10.28
  • Published : 2021.10.31

Abstract

This study addresses on the design of performance monitoring system for the time synchronization service of the enhanced long-range navigation (eLoran) system, which has a representative ground-wave radio broadcast system capable of providing positioning, navigation, timing and data (PNT&D) services. The limitations of time-synchronized systems due to the signal vulnerabilities of the global navigation satellite system (GNSS) are explained, and the performance monitoring system for the eLoran timing service as a backup to the GNSS is proposed. The time synchronization service using eLoran system as well as system configurations and the user requirements in the differential Loran (dLoran) system are described to monitor the time synchronization performance. The results of the designed system are presented for long-term operation in the eLoran testbed environment. As the results of time performance monitoring, we were able to verify the time synchronization precision within 43.71 ns without corrections, 22.52 ns with corrections. Based on these results, the eLoran system can be utilized as a precise time synchronization source for GPS timing backup.

본 논문은 지상파 기반의 측위·항법·시각(PNT, Positioning, Navigation, and Timing) 서비스의 대표격인 eLoran(enhance LOng RAnge Navigation) 시스템의 시각동기 성능 모니터링 시스템의 설계에 관한 것으로서, GNSS(Global Navigation Satellite System)의 신호 취약성에 따른 시각동기시스템의 한계에 대해 설명하고, 이에 대한 백업시스템으로 대표적 지상파항법시스템인 eLoran 시스템의 시각동기 성능모니터링 시스템에 대해 중점적으로 다룬다. eLoran 시스템을 이용한 시각동기 서비스 및 이에 대한 성능감시를 위한 보정기준국(dLoran, differential Loran) 관점에서의 시각동기 성능모니터링 시스템의 구성과 그 요구성능에 대해 설명한다. 또한 eLoran 테스트베드 환경 내 시각동기 모니터링 시스템의 장기 시범운영을 통해서, eLoran 시각동기서비스의 성능을 분석한다. 시각동기 성능모니터링 시스템을 이용한 성능 분석결과 보정 전 43.71 ns, 보정 후 22.52 ns (rms)의 시각정밀도를 나타내었으며, 이를 통해서 정밀시각 동기원으로 eLoran 서비스가 충분히 GPS 백업 시각동기시스템으로 활용이 가능함을 확인할 수 있었다.

Keywords

Acknowledgement

본 논문은 해양수산부의 재원과 해양 PNT 연구단의 관리 하에 수행된 "지상파통합항법시스템(R-Mode) 기술개발[PMS4710]" 과제의 연구결과 중 일부입니다.

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