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A Long-Term Comparison Between GPS Carrier-Phase and Two-way Satellite Time TransferWe have conducted GPS carrier-phase time-transfer experiment between the Master Clock at USNO in Washington DC and the Alternate Master Clock at Schriever Air Force Base near Colorado Springs, Colorado. These clocks are also monitored on an hourly basis with two-way satellite time-transfer (TWSTT) measurements. We compare the performance of the GPS carrier-phase and TWSTT systems over a 167-day period. Apart from an overall constant time offset (due to unknown delays in the GPS hardware at both ends), we find that the systems agree within +/- 1ns, with a drift of 1.9 +/- 0.1 ps/d. For averaging times of a day, the carrier-phase and TWSTT systems have a frequency uncertainty of 2.5 and 5.5 parts in 10(exp 15), respectively.
Document ID
20050050977
Acquisition Source
Goddard Space Flight Center
Document Type
Conference Paper
Authors
Larson, Kristine (Colorado Univ. Boulder, CO, United States)
Nelson, Lisa (National Inst. of Standards and Technology Boulder, CO, United States)
Levine, Judah (National Inst. of Standards and Technology Boulder, CO, United States)
Parker, Tom (National Inst. of Standards and Technology Boulder, CO, United States)
Powers, Edward D. (Department of the Navy Washington, DC, United States)
Date Acquired
September 7, 2013
Publication Date
January 1, 1999
Publication Information
Publication: Proceedings of the 30th Annual Precise Time and Time Interval (PTTI) Systems and Applications Meeting
Subject Category
Instrumentation And Photography
Funding Number(s)
CONTRACT_GRANT: NAG5-6147
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.

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IDRelationTitle20050050957Collected WorksProceedings of the 30th Annual Precise Time and Time Interval (PTTI) Systems and Applications Meeting
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