NavCom SF-2050 Rev.D User Manual
Page 62
SF-2050 User Guide - Rev. D
Proprietary commands those messages sent to and
received from
GPS
equipment produced by NavCom
Technology, Inc. own copyrighted binary language.
pseudo-random noise (
prn
) a sequence of data that
appears to be randomly distributed but can be exactly
reproduced. Each
GPS
satellite transmits a unique
PRN
in its signals.
GPS
receivers use
PRN
s to identify and
lock onto satellites and to compute their pseudoranges.
Pseudorange the apparent distance from the
reference
station
’s antenna to a satellite, calculated by multiplying
the time the signal takes to reach the antenna by the
speed of light (radio waves travel at the speed of light).
The actual distance, or
range
, is not exactly the same
because various factors cause errors in the
measurement.
PVT
GPS
information depicting Position, Velocity, Time
in the NCT proprietary message format.
Radio Technical Commission for Maritime Services
see
RTCM
.
range the distance between a satellite and a
GPS
receiver’s antenna. The
range
is approximately equal to
the
pseudorange
. However, errors can be introduced by
atmospheric conditions which slow down the radio
waves, clock errors, irregularities in the satellite’s orbit,
and other factors. A
GPS
receiver’s location can be
determined if you know the ranges from the receiver to
at least four
GPS
satellites. Geometrically, there can only
be one point in space, which is the correct distance
from each of four known points.
RCP a NavCom Technology, Inc. proprietary processing
technique in which carrier phase measurements, free of
Glossary-60