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The Role of LORAN Timing in Telecommunications



Michael A. Lombardi, Chuck Norman, William J. Walsh


The telecommunications industry in the United States has performance requirements for time synchronization and frequency control that must be met in order for land and mobile telephone services, wireless networks, and other applications to remain operational. Many of these services now heavily rely upon signals from the Global Positioning System (GPS) satellites as their time and frequency reference source, making them vulnerable to an extended GPS signal outage. This paper describes LORAN?s role as a backup or alternative timing reference source to GPS for wired and wireless telecommunications networks. It discusses GPS vulnerabilities and the possible consequence of a prolonged GPS signal outage. It explores how LORAN meets all of the required characteristics of a GPS backup system, not only the requirements for time and frequency performance, but also the requirements for signal coverage area, reliability, national security, and traceability to national and international time standards.
Proceedings Title
Proceedings of the 2006 Radio Technical Commission for Maritime Services (RTCM) Symposium


LORAN, synchronization, telecommunications, UTC


Lombardi, M. , Norman, C. and Walsh, W. (2006), The Role of LORAN Timing in Telecommunications, Proceedings of the 2006 Radio Technical Commission for Maritime Services (RTCM) Symposium, [online], (Accessed June 20, 2024)


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Created May 8, 2006, Updated January 27, 2020