Goplanet Mars 200, Руководство пользователя

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About GPS
Global Position System (GPS) is a satellite system developed by Department of
Defense of US. GPS consists of 32 satellites that encircle the earth and are
11,000 miles away from the ground. These satellites make two circles of the
earth per day and emit signals of extremely low power which will be received and
recorded by 5 ground stations. These ground stations will use precise time
signals to confirm accurate position of each satellite. Your GPS receiver can
“pick” signals sent out by the satellites. And an accurate latitude, longitude and
height can be determined through calculation on positions and distances of at
least 4 satellites.
WAAS (Wide Area Augmentation System) can enhance the precision of GPS. It
is designed by Federal Aviation Administration of US and mainly used to
enhance precision of GPS on a plane. WAAS is combined with extra ground
station groups which were set up in the places located precisely. These ground
stations can work together with a master console so as to improve accuracy of
satellite signals and reduce errors to about 3 meters.