DGPS

Topcon dGPS config notes

2008 will use it in static recording more - ie no radio link between (rtk) but we record files on each unit then postprocess in Southampton.

test logs:

used pccdu to setup default+standalone mode on each unit (rather than rtk) topcon say it can be in either.

ensured code&carrier multipath and coop tracking options enabled (and coop tracking loop)

10min recordings yielded position to about 5mm while 50mins was about 2-3mm precision!

got results with +- 6cm but static testpoint shown as moved!

worth noting that pccdu downloads files at 10kB/s - 10mins of file with 7 sats was about 470kB

We can download RINEX files from ftp://ftp.lmi.is/GPS/HOFN/ - slightly out of date/slow or ftp://igs.bkg.bund.de/IGS/obs/ which is easier (do it by day number)

This sky view shows that the southern sky is the main source of gps sats.

Mid-day there are probably enough sats visible. (although there are more in the evening)