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A Laser-Cooled Frequency Standard for GPS



Thomas P. Heavner, Stephan E. Barlow, Marc A. Weiss, Neil Ashby, Steven R. Jefferts


NIST is in an initial phase of developing a prototype laser-cooled atomic frequency standard (AFS) for potential use in a future GPS system. The expected fractional frequency stability or Allan deviation, ςy(τ), will be 2x10-13 at one second, improving as the square-root of the averaging time to 7x10-16 at one day. This corresponds to an expected time dispersion of 0.060 ns at one day, or 0.02 m of user range error (URE). We discuss design and development process underway at NIST, as well as capabilities enabled by this AFS in GPS.
Proceedings Title
Proceedings of the ION GNSS 2011 Conference
Conference Dates
September 20-23, 2011
Conference Location
Portland, OR
Conference Title


Atomic clock, Cesium, GPS, Laser Cooling


Heavner, T. , Barlow, S. , Weiss, M. , Ashby, N. and Jefferts, S. (2011), A Laser-Cooled Frequency Standard for GPS, Proceedings of the ION GNSS 2011 Conference, Portland, OR (Accessed June 25, 2024)


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Created September 20, 2011, Updated February 19, 2017