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A common-view disciplined oscillator



Michael A. Lombardi, Aaron P. Dahlen


This paper describes a common-view disciplined oscillator (CVDO) that locks to a reference time scale through the use of common-view Global Positioning System (GPS) satellite measurements. A Proportional-Integral-Derivative (PID) controller obtains near real-time common-view GPS measurements from the Internet and provides steering corrections to a local oscillator. A CVDO can be locked to any time scale that makes real-time common-view data available and can serve as a high accuracy, self-calibrating frequency and time standard. Measurement results are presented where a CVDO is locked to UTC(NIST), the coordinated universal time scale maintained at the National Institute of Standards and Technology (NIST) in Boulder, Colorado.
Review of Scientific Instruments


disciplined oscillator, GPS, Internet, time scale, time transfer


Lombardi, M. and Dahlen, A. (2010), A common-view disciplined oscillator, Review of Scientific Instruments, [online], (Accessed May 20, 2024)


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Created May 24, 2010, Updated February 19, 2017