[time-nuts] Clock quality: alternatives to ADEV
Magnus Danielson
magnus at rubidium.dyndns.org
Sat Apr 12 06:36:47 EDT 2014
On 10/04/14 19:24, Richard (Rick) Karlquist wrote:
> The trouble with ADEV is that if you average
> a long time it papers over anomalous events
> like crystal jumps.
ADEV is about characterizing noise powers. The better variants such as
TOTADEV and TheoADEV will be even more efficient at suppressing a
crystal jump. It's just not the right tool for crystal jumps.
> An alternative measure
> might be to, instead of averaging, simply
> keep track of the worse case change in frequency
> during 1 sample period. Sort of like peak jitter
> versus rms jitter.
MAFE (Maximum Average Frequency Error) might be a suitable measure to
apply, it's the frequency relative to MATIE (Maximum Average Time
Interval Error).
MTIE (Maximum Time Interval Error) has been used for a long time
characterize longer term systematics.
Maybe just doing a MFE (Maximum Frequency Error) might be the tool at hand.
Just to get the ideas rolling.
Cheers,
Magnus
More information about the time-nuts
mailing list