Ag Leader GPS 5100 User Guide - Manual (Page 18)

2 Overview
1 2 GPS 5100 Receiver User Guide
Subscription-based corrections
The GPS 5100 receiver uses OmniSTAR HP or OmniSTAR VBS
differential corrections in the same way that it uses WAAS/EGNOS
corrections.
OmniSTAR corrections are provided on a subscription basis.
The corrections that are produced by OmniSTAR HP algorithms are
more accurate than the corrections that are produced by OmniSTAR
VBS algorithms. The accuracy of the positions reported using
OmniSTAR HP 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 the distance to the closest OmniSTAR
corrections base station. OmniSTAR is continually improving the
service.
For more information about OmniSTAR, go to the OmniSTAR
website at www.omnistar.com. For information about activating an
OmniSTAR subscription, see OmniSTAR, page 31.
26.3
Autonomous GPS positioning
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
is comparable to the other methods.