C-Nav 2050M, Руководство пользователя

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C-Nav2050 User Guide
Infrastructure
The system utilizes the GPS satellite system, L-band
communication satellites, and a worldwide network of
reference stations to deliver real-time high precision
positioning.
To provide this unique service, C-Nav has built a global
network of dual-frequency reference stations, which
constantly receive signals from the GPS satellites as
they orbit the earth. Data from these reference stations
is fed to two USA processing centers in Torrance,
California and Moline, Illinois where they are processed
to generate the differential corrections.
From the two processing centers, the correction data is
fed via redundant and independent communication links
to satellite uplink stations at Laurentides, Quebec,
Canada; Perth, Australia; Burum, the Netherlands;
Santa Paula, California; Auckland, New Zealand; and
Southbury, Connecticut for rebroadcast via the geo-
stationary satellites.
The key to the accuracy and convenience of the C-Nav
system is the source of SBAS corrections. GPS
satellites transmit navigation data on two
L-band frequencies. The C-Nav reference stations are
all equipped with geodetic-quality, dual-frequency
receivers. These reference receivers decode GPS
signals and send precise, high quality, dual-frequency
pseudorange and carrier phase measurements back to
the processing centers together with the data
messages, which all GPS satellites broadcast.
At the processing centers, C-Nav's proprietary
differential processing techniques used to generate real
time precise orbits and clock correction data for each
satellite in the GPS constellation. This proprietary Wide
Area DGPS (WADGPS) algorithm is optimized for a
dual-frequency system such as the C-Nav Correction
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