Kongsberg Seatex Seapath 200, Installation Manual

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Seatex Seapath 200 Installation Manual, rev. 13 Installation
11
3.3 Location of the system parts
The following sections contain hints regarding mounting of the various system parts:
3.3.1 The GPS antennas
For the GPS antennas, consider the following:
•
The space above the antennas has to be free of obstructions of any kind. The antenna
should be protected from direct illumination of radar beams and other transmitting
antennas such as Inmarsat antennas. Seapath is more sensitive for blocking and reflections
(multipath) of GPS signals than GPS sensors that only utilises pseudo-range data. This
since Seapath also utilises carrier phase measurements for heading determination, and
both GPS antennas need to see at least two common satellites at the same time.
The GPS antennas have to be mounted in a way that avoids blocking of the GPS
signal.
•
In order to reduce problems due to multipath effects the GPS antennas have to be mounted
above the nearest deck at a height which is equal to the width of this deck or more.
•
The Antenna Bracket has to be mounted in such a way that torsion movement relative to
the ship's hull is kept at an absolute minimum.
Note
If the Antenna Bracket supplied by Seatex is not used, it is important that the
antennas are rigidly mounted so that the distance between the antennas does not
change due to vibrations or accidental dislocation.
CAUTION