NavCom SF-2050 Rev.D - Manual (Page 65)

SF-2050 User Guide - Rev. D
SNR see signal-to-noise Ratio.
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 C).
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-63