Page 130 - Electronic Navigation Cyber Book

Horizontal dilution of position. A measure of the quality of a
HDOP solution in terms
of latitude/longitude.

Inclination The angle formed between the eastern end of the equatorial
plane and a satellite
orbit. For GPS orbits it is 55°.
Kepler's Satellites in orbit follow an ellipse as defined by Johannes
laws Kepler.
Li The GPS primary transmission frequency; 1575.42 MHz.
L2 The GPS secondary transmission frequency; 1227.6 MHz.
MCS The GPS Master Control Station situated at Colorado Springs.
National Maritime Electronics Association. An organization of
NMEA manufacturers and distributors responsible for agreeing the
standards of interfacing between various electronic shipboard
systems.
NOTAM FAA's Notice to Airmen regarding GPS service interruption.
P code Precision code. A PRN code operating at 10.23 MHz.
PDOP Precision dilution of position.
Perigee The closest point of approach to the earth reached by an
orbiting satellite.
PPS GPS Precise Positioning Service.
PRN Pseudo-random noise.
RTCM Radio Technical Commission for Maritime Services.
An accuracy that is achievable 50% of the time in all
SEP
dimensions.
SOG Speed over ground.
SPS GPS Standard Positioning Service.
SV Space vehicle - a satellite.
TDOP Time dilution of precision.

TTFF Time to first fix. Used to identify how long a GPS receiver takes
before a fix is available.
TTSF Time to subsequent fix.
TRN Turn
URE User range error.
User equivalent range error. Determined by summing the
UERE squares of the individual range errors and then taking the
square root of the total.
USCG United States Coast Guard.
USNS United States NOTAM Service.
ULS Satellite uplink station.
UTC Universal time coordinated.
Universal transverse Mercator. A grid co-ordinate system that
UTM
projects global sections onto a flat surface

© 2018 Digital Galaxy Index 130