NavCom Technology GPS Products, User Manual

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SF-2050 User Guide - Rev. E
Differential
GPS
(
DGPS
) a positioning procedure that
uses two receivers, a
rover
at an unknown location and
a reference s ation at a known, fixed location. The
reference station
computes corrections based on the
actual and observed ranges to the satellites being
tracked. The coordinates of the unknown location can
be computed with sub-meter level precision by
applying these corrections to the satellite data received
by the
rover .
t
Dilution of Precision (
DOP
) a class of measures of the
magnitude of error in
GPS position
fixes due to the
orientation of the GPS satellites with respect to the GPS
receiver. There are several
DOP
s to measure different
components of the error. Note: this is a unitless value.
see also
PDOP .
DOP see
Dilution of Precision
.
dual-frequency a type of
GPS
receiver that uses both
L1 and L2 signals from
GPS
satellites. A
dual-frequency
receiver can compute more precise position fixes over
longer distances and under more adverse conditions
because it compensates for ionospheric delays. The SF-
2050 is a dual frequency receiver.
dynamic mode when a
GPS
receiver operates in
dynamic mode , it assumes that it is in motion and
certain algorithms for
GPS position
fixing are enabled in
order to calculate a tighter
position
fix.
EGNOS (European Geostationary Navigation Overlay
Service) a European satellite system used to augment
the two military satellite navigation systems now
operating, the US
GPS and Russian GLONASS systems.
elevation distance above or below Local Vertical
Datum.
Glossary-55