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Area Piezoelectric, dielectric and electrostatic devices and associated materials for frequency control, selection and detection / Piezoelectric and dielectric oscillators

IEV ref561-03-02

en
Allan variance of fractional frequency fluctuation
unbiased estimate of the preferred definition in the time domain of the short-term stability characteristic of the oscillator output frequency given by

σ y 2 ( τ ) 1 M1 k=1 M1 ( Y k+1 Y k ) 2 2 MathType@MTEF@5@5@+=feaagCart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLnhiov2DGi1BTfMBaeXatLxBI9gBaerbbjxAHXgarqqtubsr4rNCHbGeaGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaqFn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpeWZqaaeqabiGaciGacaqadmaadaqaaqaaaOqaaiabeo8aZnaaBaaaleaacaWG5baabeaakmaaCaaaleqabaGaaGOmaaaakmaabmaabaGaeqiXdqhacaGLOaGaayzkaaGaeyyrIa0aaSaaaeaacaaIXaaabaGaamytaiaacobicaaIXaaaamaaqahabaWaaSaaaeaadaqadaqaaiaadMfadaWgaaWcbaGaam4AaiabgUcaRiaaigdaaeqaaOGaai4eGiaadMfadaWgaaWcbaGaam4AaaqabaaakiaawIcacaGLPaaadaahaaWcbeqaaiaaikdaaaaakeaacaaIYaaaaaWcbaGaam4Aaiabg2da9iaaigdaaeaacaWGnbGaai4eGiaaigdaa0GaeyyeIuoaaaa@51A1@

where

Yk are the average fractional frequency fluctuations obtained sequentially, with no systematic dead time between measurements;

τ is the sample time over which the measurements are averaged;

M is the number of measurements

Note 1 to entry: The confidence of the estimate improves as M increases.

Note 2 to entry: This entry was numbered 561-04-18 in IEC 60050-561:1991.


fr
variance d’Allan de la fluctuation de fréquence relative, f
estimation non biaisée de la définition préférée dans le domaine temporel de la caractéristique de stabilité à court terme de la fréquence de sortie de l’oscillateur donnée par

σ y 2 ( τ ) 1 M1 k=1 M1 ( Y k+1 Y k ) 2 2 MathType@MTEF@5@5@+=feaagCart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLnhiov2DGi1BTfMBaeXatLxBI9gBaerbbjxAHXgarqqtubsr4rNCHbGeaGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaqFn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpeWZqaaeqabiGaciGacaqadmaadaqaaqaaaOqaaiabeo8aZnaaBaaaleaacaWG5baabeaakmaaCaaaleqabaGaaGOmaaaakmaabmaabaGaeqiXdqhacaGLOaGaayzkaaGaeyyrIa0aaSaaaeaacaaIXaaabaGaamytaiaacobicaaIXaaaamaaqahabaWaaSaaaeaadaqadaqaaiaadMfadaWgaaWcbaGaam4AaiabgUcaRiaaigdaaeqaaOGaai4eGiaadMfadaWgaaWcbaGaam4AaaqabaaakiaawIcacaGLPaaadaahaaWcbeqaaiaaikdaaaaakeaacaaIYaaaaaWcbaGaam4Aaiabg2da9iaaigdaaeaacaWGnbGaai4eGiaaigdaa0GaeyyeIuoaaaa@51A1@

Yk sont les fluctuations de fréquence relative moyennes obtenues de manière séquentielle, sans temps mort systématique entre les mesures;

τ est la durée d’échantillon sur laquelle la moyenne des mesures est calculée;

M est le nombre de mesures

Note 1 à l’article: Le niveau de confiance de l’estimation augmente au fur et à mesure de l’augmentation de M.

Note 2 à l'article: Cet article était numéroté 561-04-18 dans l'IEC 60050-561:1991.


ar
تباين اختلاف "آلان" لتموج التردد الجزئى

de
Allan-Varianz, f
Varianz der relativen Frequenzabweichungen, f

es
varianza de Allan de la fluctuación de frecuencia fraccional

it
varianza di Allan della fluttuazione di frequenza relativa

ko
분수 주파수 진동의 앨란 분산

ja
周波数揺らぎのアラン分散

pl
wariancja Allana względnych fluktuacji częstotliwości, f

pt
variância de Allan da flutuação dos desvios da frequência relativa

zh
相对频率起伏的阿仑方差

Publication date: 2016-07
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