Trimble Outdoors aggps 332 Benutzerhandbuch

AgGPS 332 GPS Receiver User Guide     11

Overview     2

The AgGPS 332 receiver uses OmniSTAR XP/HP or OmniSTAR VBS 
differential corrections in the same way that it uses WAAS/EGNOS 
corrections but are provided on a subscription basis.

The corrections that are produced by OmniSTAR XP/HP algorithms are 
more accurate than the corrections that are produced by OmniSTAR 
VBS algorithms. The accuracy of the positions reported using 
OmniSTAR HP/XP increases with the time that has elapsed since the 
instrument was turned on. This process is called convergence. 
Convergence to where the error is estimated to be below 30 cm 
(approximate 12 inches) typically takes around 20 minutes. Factors that 
influence the time to convergence include the environment, the 
geographical location and  for OmniSTAR HP, the distance to the 
closest OmniSTAR corrections base station. OmniSTAR is continually 
improving this  service. OmniSTAR XP is not dependent on distance to 
base station  

For more information about OmniSTAR, go to the OmniSTAR website 
at 

. Alternatively, call 888 883 8476 (USA or Canada). 

For information about activating an OmniSTAR subscription, go to the 
OmniSTAR website (

) or call 888-883-8476 (USA or 

Canada).

Autonomous GPS positioning uses no corrections. The rover receiver 
calculates its position using only the GPS signals it receives. This 
method does not have high absolute accuracy, but the relative accuracy 
can be comparable depending on geographic location and overall 
environment

.