Message ID: 1074
Entry time: Tue Sep 21 01:52:05 2010
In reply to: 1053
Reply to this: 1547

Author:

Dmass

Type:

Misc

Category:

Doubling

Subject:

Doubling results summary

I was concerned that what I thought was fractional frequency deviation might be different from clock peoples definitions of fractional frequency stability. I looked around a bit and here is what I found out:

This is the Bureau of standards note debating what standard to use for Freq. Stablity. It discusses Allan Deviation versus Spectral Noise Density, and their relationship

AN HP note explaining the relationship between Allan Deviation and Spectral Density - see page 63 for general integral relation between the two quantities

David Allan document explaining the relation between Allan Dev and Spectral Density - He doesn't give the exact form of the transfer function you should apply to get Allan Variance from a PSD, but he shows plots of it which are consistent with the previous analytic form.

I used this to make some plots of the Allan Deviation from my power spectra, the units of Allan Deviation are dimensionless, as its a measure of fractional instability.

I found a typo in the old code, uploaded new plot.