GLOBALSAT GH-561 User Manual - Manual (Page 45)

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13. Glossary
Activity
Relates to data being transmitted from GH-561. Activity is a history
or log of events. Activity data includes time or distance updates.
Waypoint
Waypoints are sets of coordinates that identify a point in physical
space. For the purposes of terrestrial navigation, these coordinates
usually include longitude and latitude, and sometimes altitude
(particularly for air navigation).
Trackpoint
The current moving trace.
Navigation
The act of determining the course or heading of movement.
2D Operating
Mode
A “two-dimensional GPS position fix” includes only horizontal
coordinates. It requires a minimum of three visible satellites.
3D Operating
Mode
A “three-dimensional GPS position fix” includes horizontal
coordinates, plus elevation. It requires a minimum of four visible
satellites.
Weak Signal
GPS signal is weak (GPS is fixing).
Receiving
Can’t find GPS (GPS turned off or broken down).
WAAS/EGNOS
Wide Area Augmentation System / European Geostationary
Navigation Overlay Service. These are two satellite-based systems
that can be used to increase the accuracy of GPS position fixes.
IPX4
The IPX4 waterproof standard is for device to protect against
splashing water without any adverse operational effects.
GMT
Greenwich Mean Time (GMT) is a term originally referring to mean
solar time at the Royal Observatory, Greenwich in England. It is
now often used to refer to Coordinated Universal Time (UTC) when
this is viewed as a time zone, although strictly UTC is an atomic
time scale which only approximates GMT in the old sense. It is also
used to refer to Universal Time (UT), which is the astronomical
concept that directly replaced the original GMT.