IEEE 1139:2008 pdf free download

IEEE 1139:2008 pdf free download.IEEE Standard Definitions of Physical Quantities for Fundamental Frequency and Time Metrology-Random Instabilities.
2. Definitions
For the purposes of this standard, the following terms and definitions apply. The Authoritative 0itionarv o/’IEEE Standards Terms [B51j should be referenced for terms not detined in this clause. If ambiguities are created bctwcen the narrative definition given here and the mathematical equation given in the text. the equation has priority.
2.1 amplitude spectrum SJ): One-sided spectral density of the normalized amplitude fluctuations, as defined in normalized amplitude fluctuations aU).
2.2 bias: The difference between the expected value of an estimator of a statistic and its correct valuc.
2.3 confidence interval: An interval of uncertainty associated with an estimate of an instability measure
from a finite number of measurements. The endpoints of a confidence interval are called con/ldence limits.
2.4 frequency spectrum S,(f): One-sided spectral density of the normalized frequency fluctuations, as
defined in normalized frequency fluctualionsy(t).
2.5 normalized amplitude fluctuations u(I): Instantaneous normalized amplitude departure from a
nominal amplitude.
2.6 normalized frequency fluctuations y(t): Instantaneous, normalized frequency departure from a nominal frequency.
2.7 phase fluctuations : Instantaneous phase departure from a nominal phase.
2.8 phase noise (If): One-half of the phase spectrum S,(f). as defined in phase spectrum S4f).
2.9 phase spectrum S4/): One-sided spectral density of the phase fluctuations.
2.10 time fluctuatlonsx(t): Instantaneous time departure from a nominal time.
2.11 time interval error (TIE): The time difference between a real clock and an ideal uniform time scale
following a time period t after perfect synchronization.
2.12 time spectrum SAf): One-sided spectral density of the time fluctuations.
2.13 two-sample deviation o.(r): Also called the Allan deviation: the square root of the two sample variance, as defined in two-sample variance 0.2( t).
2.14 two-sample variance 2(r): Also called the variance: one-half the time average of the square of the difference between the averages of normalized frequency fluctuations over two adjacent time intervals of length r. with no dead time between the two averaging intervals.
3. Standards for characterizing or reporting measurements of frequency, amplitude, and phase instabilities.