[time-nuts] New Subscriber, DIY GPSDO project (yes, another one)

[Poul-Henning Kamp]

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In message <be8c8c2f-217b-13b8-c9ce-c4150c549852 at rubidium.se>, Magnus Danielson
 writes:

>It should be said that Kalman is kind of optimum for "white" noise
>(what-ever that is), but we are far from white noise. Variants of Kalman
>filters use noise-colour compensation of some sort, and that kind of
>solves some of the issues. It does not fit the problem perfectly. This
>is why time-scale algorithms is not directly Kalman filters but only
>Kalman-esque to some degree.

And that line of thought brings us to the stochastic-ish model which
timing.com used on three 5071A and (three?) GPS's for the LORAN-C
modernization.

It's a very interesting paper and a very good idea, which works
becuase their frequency source "bottoms out" in the MVAR plot:
Frequency drift would mean you too many degrees of freedom.

The only chance I see of doing something like that, would be a Rb
where the lowest point on the MVAR plot is very close to 12h, or
even better 24h, where the GPS is similarly optimal.

Que the HP5065A...

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