Hemisphere GPS Crescent V100 Series, Руководство пользователя

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2: Crescent V100 Operation
GPS O
VERVIEW
For your convenience, both the GPS and SBAS operation of the
Crescent V100 features automatic operational algorithms. When
powered for the first time, the Crescent V100 system will perform a
“cold start,” which involves acquiring the available GPS satellites in
view and the SBAS differential service.
If SBAS is not available in your area, an external source of RTCM
SC-104 differential corrections may be used. If you choose to use
an external source of correction data, you will need to ensure that
the external source supports an eight data bit, no parity and one
stop bit configuration (8-N-1).
GPS Operation
The GPS engine is always operating, regardless of the DGPS mode
of operation. The following sections describe the general operation
of the Crescent V100’s internal GPS engine.
Automatic Tracking
The GPS engine within the Crescent V100 automatically searches
for GPS satellites, acquires the signals and manages the navigation
information required for positioning and tracking. This is a
hands-free mode of operation.
Receiver Performance
The Crescent V100 works by finding four or more GPS satellites in
the visible sky and uses the information those satellites provide to
compute an appropriate position (within 5 meters (5.47 yards)).
Since there is some error in the GPS data calculations, the
Note: Differential source and status have no impact on
heading. They only have an impact on positioning.