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2.2.4 VHF Antenna Installation
The quality and positioning of the antenna is the most important factor dictating AIS performance.
It is recommended that a VHF antenna with omni directional vertical polarization be specifically
tuned for AIS operation band. Since the range of VHF signals is largely decided by line of sight
distance, AIS antenna should be placed as high as possible and at least 5 meters away from any
constructions made of conductive materials.
To avoid interference, the VHF antenna location
should be placed in accordance to Figure 2-2-4.
Figure 2-2-4 VHF/GPS Antenna Location
We recommend you choose AMEC AIS VHF antenna. To save space, you can also choose
VHF/GPS combo antenna provided by AMEC
Ensure a free
360˚ horizon with
a vertical observation of 5˚.
5˚
High power transmitting antenna
3m
Ensure the GPS antenna is not
within the transmitting beam of other
high power transmitting antenna.
VHF
Antenna.
Other VHF
Antenna
The recommended
vertical distance
between antennas
is 2m.
The
recommended
horizontal
distance between
antennas is 10m.
Other transmitting
antenna
10m
The recommended horizontal
distance between GPS antennas
and other antennas is 3m.