[time-nuts] Common sky pps errors for any GPSDOs?
Lux, James P
james.p.lux at jpl.nasa.gov
Tue Jan 6 01:01:35 EST 2009
On 1/5/09 9:27 PM, "SAIDJACK at aol.com" <SAIDJACK at aol.com> wrote:
> Hi Matt,
> having 140ps matching of the 1PPS between units is the equivalent of knowing
> your antenna position to within ~0.14 feet total error max.
> Thats less than one inch error per antenna!
> That would require some serious antenna surveying :) This accuracy is
> impossible to achieve with timing GPS receivers without
> carrier-phase/post-processing as far as I know.
On the other hand, if the antennas aren't moving, then you could spend
arbitrarily long surveying the position.
Or, if you have stable phase relationships (not necessarily known, but
stable), you can do some sort of self survey using am arbitrary receive
signal like Bernie Steinberg, et al.,'s work with the Radio Camera at Valley
Forge Research Center.
There's also been some work with uplink arraying in the Deep Space Network
(but, of course, they have masers and optical fibers, etc.)
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