[time-nuts] nuts about position

[Peter Monta]

Hi Tom,


> It that's still not close enough to 0.3 m, is one then forced to use more
> expensive multi-frequency (L1/L2) or multi-band (GPS, GLONASS, Galileo) to
> achieve this level of precision? If so, how cheaply can one do this? Or is
> the learning curve more expensive than just hiring an survey specialist to
> make a one-time cm-level measurement for you?
>

I suspect just L1 would be fine in areas with dense CORS.  I have not tried
it, but how about this ultra-cheap strategy:

1. obtain L1 observables with a cheap board and cheap patch antenna;
convert to RINEX
2. synthesize fake L2 data, using nominal iono conditions, and add it to
the RINEX
3. submit to NOAA's rapid static solver, OPUS-RS, which currently accepts
only dual-frequency data
4. examine the quality report from OPUS-RS to see if the ambiguities were
reliably resolved

But this is a bit of a dicey science project; I'd suggest that the
researcher borrow a survey receiver for a few days (mild learning curve for
the online solver tools) or hire a surveyor (no learning curve).

Cheers,
Peter