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The Potential Role of Enhanced LORAN-C in the National Time and Frequency Infrastructure



Michael A. Lombardi, Thomas P. Celano, Edward Powers


The United States LORAN-C network has been significantly upgraded in recent years so that it might better serve as a backup to the Global Positioning System (GPS) both for navigation and timing applications. This paper examines the potential role of the enhanced LORAN-C network by comparing it not only to GPS, but to the other network and wireless distribution systems that anchor the time and frequency infrastructure for the United States. It then ranks enhanced LORAN-C amongst these systems as a reference source for time-of-day, precise time synchronization, and frequency. The rankings are primarily based on the estimated accuracy and stability that can be obtained with each system, but other factors are discussed including availability, coverage area, acquisition time, reliability, redundancy, and traceability to national and international standards.
Proceedings Title
Proc. 2005 Intl. Loran Assoc. Mtg.


broadcast services, frequency, LORAN-C, time, time-of-day, traceability


Lombardi, M. , Celano, T. and Powers, E. (2005), The Potential Role of Enhanced LORAN-C in the National Time and Frequency Infrastructure, Proc. 2005 Intl. Loran Assoc. Mtg., [online], (Accessed April 17, 2024)
Created October 17, 2005, Updated January 27, 2020