Almanac DataThe satellite constellation information (including location and health of satellites) that
is transmitted to your receiver from every GPS satellite. Almanac data must be acquired before GPS
navigation can begin.
Bearing (BRG)The compass direction from your position to a destination.
Course Over Ground (COG)
Direction of movement relative to a ground position.
Crosstrack Error (XTK)
The distance you are off a desired course in either direction.
Desired Track (DTK)The compass course between the from and to waypoints.
Differential GPS (DGPS)
An extension of the GPS system that uses land-based radio beacons to
transmit position corrections to GPS receivers.
Estimated Time of Arrival (ETA)
The time of day of your arrival at a destination.
Estimated Time Enroute (ETE)The time remaining to your destination at your present speed.
Grid
A coordinate system that projects the earth on a flat surface, using square zones for position mea-
surements.
Ground Speed (SOG)
The velocity you are traveling relative to a ground position.
Latitude
A north/south measurement of position perpendicular to the earths polar axis.
Longitude
An east/west measurement of position in relation to the Prime Meridian, an imaginary
circle that passes through the north and south poles.
Position
An exact, unique location based on a geographic coordinate system.
Sensitivity
A measure of how sensitive the sounder is to sonar echoes.
Speed Through Water (STW)
The speed you are traveling relative to the waters surface.
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SECTION
E
APPENDIX
Glossary