NavCom NCT-2030M Rev.C - Manual (Page 48)

NCT-2030M User Guide - Rev. C
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
NCT-2030M 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-46