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Remote Time Calibrations via the NIST Measurement and Analysis Service



Michael A. Lombardi, Andrew N. Novick


NIST now offers a new remmote calibration service desinged to assist laboratories who maintain an accurate local time standard. The service monitors the local time standard by continuously comparing it to the national time standard, and reports the compariosn results to the customer in near real time. This new service, called the NIST Time Measurement and Analysis Services or TMAS, works by making simultaneous common-view measurements at NIST and at the customers laboratroy of up to eight Global Positioning System (GPS) satellites. Each customer receives a time measurement system that performs the measurements and sends the results to the NIST via the Internet for instant processing. Customers can then view their standards performace with respect to NIST in near real time, using an ordinary web browser. Time is measured with combined standard uncertainty of > 15 nanoseconds, and multi-channel GPS common view technique used by the service and the measurement system sent to each customer. It also explains how NIST calibrates eachmeasuremtn system prior to shipment, how measurement results are reported to the customer, and how the measurement uncertainties are estimated.
Measure: The Journal of Measurement Science


calibration, frequency, GPS, measurement methods, time


Lombardi, M. and Novick, A. (2006), Remote Time Calibrations via the NIST Measurement and Analysis Service, Measure: The Journal of Measurement Science, [online], (Accessed June 16, 2024)


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Created December 1, 2006, Updated February 19, 2017