Viewing GPS information
To view and monitor GPS information:
- Select GPS Data
from the navigation window 
. Positioning information is displayed.
The position of the vehicle is indicated by the latitude and longitude values.
The Easting and Northing values show the Universal Transverse Mercator (UTM) position and zone of the vehicle. They are expressed in meters.
The grid numbers on the east-west (horizontal) axis are called the Eastings, and the grid numbers on the north-south (vertical) axis are the Northings.
- Select the Vehicle Orientation tab
.
The altitude, heading (degrees), effective vehicle speed and roll/pitch (degrees) are displayed.
Roll is the left/right tilt of the vehicle.
Pitch is the forward/backward tilt of the vehicle.
- Select the GPS Accuracy tab
.
This displays the number of satellites available, the correction age (seconds) and the HDOP (lower value indicates better accuracy) and HRMS (lower value indicates better accuracy).
Note: The HDOP (Horizontal Dilution of Precision) indicates the effect on precision of a number of satellite sources and their geometry. Keep the antennae clear of obstructions to maintain accurate GPS readings.
|
HDOP < 1.0 |
Maximum accuracy |
|
HDOP between 1.0 and 4.0 |
Average accuracy |
|
HDOP > 4 |
Poor accuracy |
|
Invalid GPS signal 0 |
No signal |
The HRMS (Horizontal Root Means Squared) calculates an average horizontal position from the source information from the satellites.