Kongsberg Seapath 320, Installation Manual

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Seapath 320
58 M300-62/rev.2
4.4.2 GNSS configuration
4.4.2.1 GNSS Geometry
The lever arm vector from the AP to GNSS antenna no. 1 has to be measured or
calculated based upon drawings or previously measured points, and entered into the
software. The antenna cable connected to GNSS1 at the back of the Processing Unit will
be GNSS antenna no. 1 in the installation. Proceed as follows:
Antenna location . Set the Antenna location coordinates for the GNSS antenna
which is defined to be antenna no. 1, normally the antenna closest to the aft of the
vessel. Check that the antenna has been located on the expected spot in the vessel
shape. If not, check the signs and the co-ordinates input for GNSS antenna no. 1, the
vessel dimension and the entered location of AP.
Antenna configuration . In the Antenna configuration section, input the antenna
type (Novatel NOV600, NOV702 or NOV702GG or GENERIC. NONE means no
antenna dome or choke ring included), baseline length 2.5 metres if the standard
Antenna Bracket is used, otherwise this length has to be measured manually and this
value entered. For the heading offset and height difference input zero. Then click on
the
Calibration wizard button to prepare the calibration. The Heading Offset and
Height Difference is automatically updated trough the Calibration wizard process.
Check that the orientation of the antennas in the vessel shape correspond with the
actual orientation in the mast. See the chapter Calibration for description on how to
use the Calibration wizard.
Note
Correct selection of antenna type is only important when raw GNSS data
are output from the Seapath for post-processing of the position accuracy.
The selection GENERIC as antanna type is used for all single-frequency
antennas (L1) and for Seapath installations that shall not use RTCM
output for post-processing. If other antennas than those listed are used,
check the following link to find the correct antenna type;
ftp://igscb.jpl.nasa.gov/igscb/station/general/rcvr_ant.tab . Other antenna
types than those listed are input in the Seapath configuration by using the
Advanced option in NavEngine configuration on the System menu.