Location Of Antenna Unit - Nera F33 Getting Started

APPENDIX A - INSTALLATION

Location of Antenna Unit

Avoiding obstructions
The antenna has a beamwidth of ±5
ideally requires a free line of sight in all directions.
Any obstruction will cause blind sectors, resulting in
signal degradation or even loss of communication
with the satellite.
Degradation of the satellite signal can only be
completely avoided by placing the antenna higher
than any obstructions. This is often not feasible and
a compromise must be made to reduce the number
of blind sectors and cost of installation.
The degree of signal degradation depends on the
size of the obstructions; the distance to them must
therefore be considered.
Preferably, all obstructions within 3 m of the antenna
should be avoided. Obstructions less than 15 cm in
diameter can be ignored beyond this distance.
Radiation precautions
Personnel should not
be admitted in areas
closer than 1 m
from the antenna.
However, no
restrictions are
required when the
antenna radome
is installed at
A-2
'
CONT D
O at 3 dB and
MICROWAVE RADIATION !
NO ADMITTANCE WITHIN 1M
least 2 m above the highest point accessible to
passengers.
Avoiding interference
Do not locate the Antenna Unit close to interfering signal
sources, or in such a position that the source (e.g. radar
antenna) radiates directly into the Nera F33 antenna.
The Antenna Unit should be separated as far as
possible from other transmitter/receiver antennas,
and preferably by at least 5 m from the antenna of
other communication or navigation equipment, such
as the antenna of the satellite navigator, the VHF
antenna, radar equipment, or other Inmarsat equip-
ment.
Compass safe distance
For installation on British or Norwegian vessels, the
antenna should be located at a distance of at least
1.0 metres from the magnetic steering compass. Be
aware that requirements may vary from one country
to another.
Other precautions
Do not place the antenna close to the funnel, as
smoke deposits will then eventually degrade antenna
performance.
The antenna should be installed so that severe
vibration and shock are avoided.
GETTING STARTED
Nera F33