Ag Leader GPS 5100 User Guide - Manual (Page 16)

2 Overview
1 0 GPS 5100 Receiver User Guide
2.6
GPS Positioning Methods
GPS positioning systems are used in different ways to provide
different levels of accuracy. Accuracy is measured in absolute terms
(you know exactly where you are in a fixed reference frame).
Table 2.4 summarizes the GPS positioning methods. Imperial units in
this table are rounded to two decimal places. The values shown are
2 sigma.
Table 2.4 Absolute accuracy of GPS positioning methods
For more information about each positioning method, see below.
26.1
RTK GPS positioning
The GPS 5100 receiver uses the RTK positioning method to achieve
centimeter-level accuracy. To use the RTK method, you must first set
up a base station. The base station uses a radio link to broadcast RTK
corrections to one or more rover receivers. The GPS 5100 receiver is a
rover receiver, so another compatible receiver, such as a Trimble
MS750™ or Trimble AgGPS® 214 GPS receiver, must be used as the
base station.
GPS positioning
method Corrections used Approximate absolute accuracy
Real-Time Kinematic
(RTK) GPS Trimble CMR
corrections broadcast
by a local base station 2.5 cm (0.98 in) + 2 ppm horizontal
accuracy,
3.7 cm (1.46 in) + 2 ppm vertical accuracy
Satellite Differential GPS OmniSTAR VBS 78 cm (30.71 in)
Satellite Differential GPS WAAS/EGNOS 95 cm (37.40 in)
OmniSTAR HP
Differential GPS OmniSTAR HP 10 cm (3.94 in) after the signal has fully
converged
1
1 Convergence time can vary, depending on the environment. Time to the first fix (submeter accuracy) is typically
<30 seconds; time to the first high accuracy fix (<10 cm accuracy) is typically <30 minutes.