[time-nuts] Question about effect of spurious frequency modulation on Allan Deviation
phk at phk.freebsd.dk
Mon Aug 6 01:24:29 EDT 2018
In message <596c5939-d99e-0b01-7ff8-2b5194fc63dc at karlquist.com>, "Richard (Rick) Karlquist" writes:
>I need to measure ADEV on a source that has spurious
>sine wave frequency modulation on it.
The biggest factor is the ratio between the tau's
you do allan for, and the modulation frequency.
If modulation divides *cleanly* into tau and preferably
with a big factor, then you can ignore it.
Otherwise things get really messy and quite intractable.
Picking your taus as multiple of the modulation is usually the best strategy.
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