>If I were worried about integrity of timing signals, I'd use a
>GPS-disciplined rubidium oscillator. I think most of the available
>devices like this are not quite as concerned with integrity as phase
>noise reduction in the normal case, so some tweaking of the
These are actually quite common in stationary timing applications. In
the early days of CDMA digital cellular development, we used GPS
receivers with rubidium oscillators in each cell site because the GPS
constellation was too incomplete to guarantee continuous coverage. I
think the commercial base stations still have rubidium oscillators
along with a spec to stay within 1 microsecond (the tolerance required
to permit soft handoff) for at least 24 hrs without seeing a GPS
satellite. This is to cover local blockages and interference as well
as any outage of the GPS constellation.
Phil
