Allan deviation

Zaman MF, Sharma A, Ayazi F (2009) The resonating star gyroscope a novel multiple-shell silicon gyroscope with sub-5 deg/hr Allan deviation bias instability. TEEE Sens 9(6) 616-124... 

J.A. Geen, S.J. Sherman, J.F. Chang, S.R. Lewis, Single-chip surface micromachined integrated gyroscope with 50/h Allan deviation, IEEE Journal of Sohd-State Circuits 37 (2002) 1860-1866. 

Allan deviation cr, (r) Statistic used to estimate frequency stability. 

Table IV shows how the Allan deviation is calculated. The left column contains a series of phase measnrements recorded once per second (r = 1 sec) in units of nanosec-...

Five noise types are commonly discnssed in the time and frequency literature white phase, flicker phase, white frequency, flicker frequency, and random walk frequency. The slope of the Allan deviation hne can identify the amount of averaging needed to remove these noise types (Fig. 7). Note that the Allan deviation does not distinguish between white phase noise and flicker phase noise. Several other statistics are used to estimate stabihty and identify noise types for various applications (Table V). 

Allan deviation OyiX) Estimates frequency stability. Particularly suited for intermediate to long-term measurements. 

Modified Allan deviation MOD cfy r) Estimates frequeney stability. Unlike the normal Allan deviation, it ean distinguish between white and flieker phase noise, whieh makes it more suitable for short-term stability estimates. 

Fig. 6. Left Deviation of the averaged beat note between the two frequency chains from the expected value for various counter gate times. Right Measured Allan standard deviation between the two chains as a function of the counter gate time...

Figure 4.1.7 The average filtered (0.45 pm) concentration based on all spot samples is plotted as a vertical line at zero deviation. The deviations of all other samples from this overall average are plotted for each of the five metals. The differences between the spot samples taken by the two monitoring teams over the 28 day trial indicate the reliability of these measurements. The deviations of the concentrations derived using the three variants of passive sampler represent values based on the overlapping 7, 14, 21 and 28 day deployment periods. The vertical bars indicate the range of concentrations found in the spot samples over the trial. This figure is adapted from Allan et al., 2008...

The Allan project was the second of the large scale expansions executed by PotashCorp and with it marked the installation of North Americas largest ground mounted friction hoist. This project deviated from others preceding it due to the placement of the hoist on the ground. 

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