NAVSTAR: The name given to GPS satellites
formed from the acronym for NAVigation System
with Time And Ranging.
Non-Directional
Beacon
(NDB):
A
low
frequency/medium
frequency
navigation
aid
sending non-directional signals that can be used for
navigation.
O
OBS: Omni-Bearing Selector.
P
Parallel Track Offset: A course that is parallel to
the designated course, but offset to the right or left
by a given distance.
PDOP: Position Dilution of Precision. See Dilution
of Precision.
R
Radial: Any of the 360 magnetic courses from a
VOR or similar navigational aid, beginning at the
navigational aid and proceeding outward in a
straight line.
RAIM:
Receiver
Autonomous
Integrity
Monitoring. A method of predicting possible system
accuracy errors that may be caused by bad satellite
data. The RAIM algorithm requires that more
satellites are available and usable than required for a
normal GPS position fix.
Range (RNG): The distance from the present
position to a destination waypoint.
S
Second: 1/60th of a minute of a degree.
Seed Position: A latitude and longitude position fix
approximately equal to the current position that the
Apollo GX55 uses to determine the location of
available satellites from which signals may be
received.
Glossary of Navigation Terms
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