Analysis of frequency biases and noise in sampled digital frequency servos for primary frequency standards

Author

Lee, W.D. ; Shirley, J.H. ; Drullinger, R.E.

Author_Institution

Time & Frequency Div., Nat. Inst. of Stand. & Technol., Boulder, CO, USA

fYear

1997

fDate

28-30 May 1997

Firstpage

249

Lastpage

252

Abstract

Unlike previous frequency standards at NIST, the main frequency servo of NIST-7, the U. S. primary frequency standard, does not lock a local oscillator to the atomic resonance. Instead it compares the frequencies of the atomic resonance and a reference oscillator. This paper presents an analysis of biases and noise in this digital servo. We show that a slight modification of the servo permits sensitive measurements for the presence of frequency biases

Keywords

atomic beams; digital control; frequency control; frequency measurement; measurement standards; physical instrumentation control; servomechanisms; statistical analysis; NIST-7; atomic resonance; biases; frequency biases; local oscillator; noise; primary frequency standard; reference oscillator; sampled digital frequency servos; software controller; square wave digital servo; statistical uncertainty; Atomic measurements; Frequency conversion; Frequency measurement; Measurement standards; Microwave oscillators; NIST; Resonance; Servomechanisms; Stability; Synthesizers;

fLanguage

English

Publisher

ieee

Conference_Titel

Frequency Control Symposium, 1997., Proceedings of the 1997 IEEE International

Conference_Location

Orlando, FL

Print_ISBN

0-7803-3728-X

Type

conf

DOI

10.1109/FREQ.1997.638554

Filename

638554