Hemisphere GPS LiteStar II Air, User Manual

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1: About LiteStar II Air
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. e-Dif is designed to minimize position drift and
prevent spiking or jumping. Typically, position drift is below 1
to 2 meters during the first hour of operation.
e-Dif should be used when you don’t need absolute positioning
data.
What Type of DGPS Does LiteStar II Air Use?
LiteStar II Air is sold with Hemisphere GPS’ SLXg3 receiver. The SLXg3
is a 12-channel GPS engine with 4 differential options:
• 300 KHz Beacon: ~ < 3 feet (1 meter) accuracy, depending
on the distance from the beacon site
300 KHz radio beacon DGPS is a differential service available
throughout the world. Redundant coverage is planned
throughout the entire U.S. Contact your Hemisphere GPS
dealer for more information on availability.
• WAAS/EGNOS: ~ < 3 feet (1 meter) accuracy (WAAS)/
~ < 16 feet (5 meter) accuracy (EGNOS - still in test mode)
WAAS is a free service of the FAA developed by Raytheon. It is
available everywhere in the U.S., including Alaska, Hawaii, and
Puerto Rico. It can also be picked up in the border areas of
Canada and Mexico.
EGNOS, a service similar to WAAS, is available in Europe and
Western Russia. However, EGNOS is still in test mode. It is
planned to be fully operational in 2004. EGNOS is a precursor
to Galileo, the full global satellite navigation system under
development in Europe.
• OmniSTAR: ~ < 3 feet (1 meter) accuracy
LiteStar II Air.book Page 8 Thursday, June 7, 2007 4:02 PM