USER’S GUIDE SF-2110, User Manual

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SF-2110 User Guide – Rev. A
of the earth.
use for GPS readings, w
an ellipsoid.
reference a
be obtained
geoid and ellipsoid at
this from the GPS altitude measurement.
GIS (Geog
computer system capable of assembling, storin
manipulating, updating,
geographica
identified a
can be used
managemen
software is
The surface of a geoid is too irregular to
hich are measured relative to
Conventionally surveyed positions
geoid. More accurate GPS readings can
by calculating the distance between the
each position and subtracting
raphical Information Systems) a
g,
analyzing and displaying
lly referenced information, i.e. data
ccording to their locations. GIS technology
for scientific investigations, resource
t, and development planning. GIS
used to display, edit, query and analyze
al
em (GPS) geometrically,
PS
.
’s
n.
the local time of the
gland.
HAE see altitude , and ellipsoid .
l the graphical objects and their associated
information.
Global Positioning Syst
there can only be one point in space, which is the
correct distance from each of four known points.
G
measures the distance from a point to at least four
satellites from a constellation of 24 NAVSTAR
satellites orbiting the earth at a very high
altitude
These distances are used to calculate the point
position.
GMT see Greenwich Mean Time .
GPS see Global Positioning System .
GPS time a measure of time. GPS time is based on
UTC, but does not add periodic ‘leap seconds’ to
correct for changes in the earth’s period of rotatio
As of September 2002
GPS time is 13 seconds
ahead of UTC.
Greenwich Mean Time (GMT)
0° meridian passing through Greenwich, En
Glossary-84