Glossary - Garmin GPSMAP 235 Sounder Owner's Manual

Almanac Data: The 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 SECTION
APPENDIX
navigation can begin.
E
Bearing (BRG): The compass direction from your position to a destination.

Glossary

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 trans-
mit 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 earth's 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 water's surface.
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