[ntp:questions] Re: Oncore driver in 4.2.0

Tim Shoppa shoppa at trailing-edge.com
Fri Nov 14 14:10:05 UTC 2003

hmurray at suespammers.org (Hal Murray) wrote in message news:<vr6jjsq88f52e5 at corp.supernews.com>...
> I'm pretty sure you could write your own version of a site
> survey routine.  Just let it run for a while and collect a
> lot of data.  You might have to hack the driver to get it.
> Anybody know how to analyze that sort of data without getting
> tricked by things like asymmetries in the reception due to
> nearby buildings on one side and things like that?

The timing Oncores will suspend the survey when the satellites in view
have a high DOP (Dilution of Position).  You get a low DOP when the satellites
in view are spread widely throughout the sky, you get a high DOP when the
satellites are not so widely spread.

NMEA message GPGSA and Motorola Binary message @@Ea return DOP information.

In an urban canyon you may never get a low DOP... but what you describe
is a half-canyon and may not be too bad.


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