NavCom RT-3020 Rev.D User Manual
Page 61

RT-3020 User Guide - Rev. E
StarFire™ a set of real-time global orbit and clock
corrections for
GPS
satellites. StarFire™ equipped
receivers are capable of real-time decimeter positioning
(see Appendix B).
Spread Spectrum Radio (SSR) a radio that uses wide
band, noise like (pseudo-noise) signals that are hard to
detect, intercept, jam, or demodulate making any data
transmitted secure. Because spread spectrum signals are
so wide, they can be transmitted at much lower spectral
power density (Watts per Hertz), than narrow band
transmitters.
SV (Space Vehicle) a
GPS
satellite.
Universal Time Coordinated (
UTC
) a time standard
maintained by the US Naval Observatory, based on
local solar mean time at the Greenwich
meridian
.
GPS
time is based on
UTC
.
UTC see
Universal time coordinated
.
WAAS (Wide Area Augmentation System) a set of
corrections for the
GPS
satellites, which are valid for the
Americas region. They incorporate satellite orbit and
clock corrections.
WAD
GPS
(
Wide Area Differential GPS
) a set of
corrections for the
GPS
satellites, which are valid for a
wide geographic area.
WGS-84 (World Geodetic System 1984) the current
standard datum for global positioning and surveying.
The WGS-84 is based on the GRS-80
ellipsoid
.
Y-code the name given to encrypted
P-code
when the
U.S. Department of Defense uses
selective availability.
Glossary-59