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of the measured clock source. The time deviation thus forms a standard deviation type of measurement to indicate the time instability of the signal source. This is a scaled variant of frequency stability of
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and is a statistical analysis of the phase stability of a signal over a given period. Measurements of a reference timing signal will refer to its TDEV and
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352:{\displaystyle \sigma _{x}^{2}(\tau )={\frac {\tau ^{2}}{3}}\operatorname {mod} \sigma _{y}^{2}(n\tau _{0})}
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is the time stability of phase versus observation interval tau. It is a scaled variant of
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TDEV is a metric often used to determine an aspect of the quality of
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or TDEV, which is the square-root of TVAR, may be derived from MDEV
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NIST SP 1065: Handbook of
Frequency Stability Analysis
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222:{\displaystyle \sigma _{x}^{2}(\tau )}
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96:June 2024
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