Title :
Predicting phase noise in crystal oscillators
Author :
Sthal, Fabrice ; Galliou, Serge ; Gufflet, Nicolas ; Mourey, Marc
Author_Institution :
CNRS, Besancon
Abstract :
In order to predict the phase noise in crystal oscillators an enhanced phase-noise model has been built. With this model, the power spectral densities of phase fluctuations can be computed in different points of the oscillator loop. They are calculated from their correlation functions. The resonator-caused noise as well as the amplifier-caused noise are taken into account and distinguished. To validate this enhanced model, the behavior of a batch of 10 MHz quartz crystal oscillators is observed and analyzed. The tested batch has been chosen in a facility production. Their associated resonators have been selected according to the value of their resonant frequency and their motional resistance. Open-loop and closed-loop measurements are given. The phase noise of the overall oscillator working in closed loop is provided by the usual active method. Theoretical and experimental results are compared and discussed
Keywords :
crystal oscillators; phase noise; 10 MHz; amplifier caused noise; closed loop measurements; correlation functions; motional resistance; open loop measurements; oscillator loop; phase fluctuations; phase noise model; power spectral density; quartz crystal oscillators; resonant frequency; resonator caused noise; Band pass filters; Fluctuations; Oscillators; Phase noise; Predictive models; Production; Resistors; Resonant frequency; Resonator filters; Transfer functions;
Journal_Title :
Ultrasonics, Ferroelectrics, and Frequency Control, IEEE Transactions on
DOI :
10.1109/TUFFC.2005.1397347
