Hemisphere GPS LiteStar II Air, Руководство пользователя

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LiteStar II Air User Guide
119
Differential Age - Time in seconds since the last DGPS
update.
Differential GPS (DGPS) - Regular GPS with an additional
correction signal added. DGPS uses a reference station at a known
point (also called a base station) to calculate and correct bias
errors. The reference station computes corrections for each
satellite signal and broadcasts these corrections to the remote, or
field, GPS receiver. The remote receiver then applies the
corrections to each satellite used to compute its fix.
e-Dif - e-Dif is available with Hemisphere GPS’ SLXg and SLXg3
receivers. e-Dif provides positions that are very accurate in relation
to a temporary reference location. This is done by gathering
continuous data from satellites for 5 to 8 minutes and then
computing a matching differential corrector for that specific
location - a process called calibration. Once e-Dif is running, it is
continually adjusted to match changing conditions on the GPS
signals caused by the atmosphere.
Firmware - A set of computer instructions stored on a memory
chip on a computer’s hard drive.
Global Positioning System (GPS) - A satellite-based navigation
system developed and operated by the U.S. Department of
Defense. GPS permits land, sea, and airborne users to determine
their three-dimensional position, velocity, and time. This service is
available to military and civilian users around the clock, in all
weather, anywhere in the world.
Greenwich Mean Time (GMT) - Greenwich Mean Time (GMT),
also known as Universal Time (UTC), is based on a 24-hour clock at
the Prime Meridian and uses one time zone.
LiteStar II Air.book Page 119 Thursday, June 7, 2007 4:02 PM