[time-nuts] Averaging Location for Position Hold

Poul-Henning Kamp phk at phk.freebsd.dk
Tue Sep 13 19:24:24 UTC 2011


In message <CAEdntmtEcC=_N1uwvNb2GZqVX8r-AXO81hw+SXF6=p+kEGbNVw at mail.gmail.com>
, =?ISO-8859-1?Q?Miguel_Gon=E7alves?= writes:

>I have a log with around 213400 samples. Each line is similar to this one
>[...]
>I averaged the minutes of latitude and longitude, the MSL (278.9) and the
>Geoid Separation (51.2) and got the following

That doesn't work very well, because the variation in your samples is
not a random distribution:  Echos and other multipath is the same every
day, the buildings that cause it do not move.

A much better strategy is to weigh the filtering by DOP quality or
even better, if you have the actual residuals from each of the
satelites used.

You may find some inspiration here:
	http://phk.freebsd.dk/raga/sneak/



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Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
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