Nera Saturn BM Marine, Руководство по установке

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Installation Manual
Saturn Bm
FREE ADMITTANCE AT
DECK LEVEL AT LEAST
2 M BELOW RADOME
MICROWAVE RADIATION !
NO ADMITTANCE WITHIN 10 M
PLANNING
Placing the Antenna
Avoiding obstructions For GMDSS installations
If the installation shall comply with GMDSS in accordance with the interna-
tional standard IEC 61097-10, please note as follows:
It is desirable that the antenna be sited in such a position that no obstacle
likely to significantly degrade the performance of the equipment appears in
any azimuth down to an elevation angle of -5 degrees.
The siting of the antenna needs careful consideration, taking into account
the adverse effect of high levels of vibration which may be introduced by
the use of a tall mast and the need to minimise shadow sectors. Objects,
especially those within 10 m of the radome which cause a shadow sector of
more than 6 degrees, are likely to significantly degrade the performance of
the equipment.
For non-GMDSS installations
The antenna has a beamwidth of 10 degrees and ideally requires a free
line of sight in all directions above an elevation angle of +5 degrees.
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 plac-
ing 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 Passengers should not be admitted in areas closer than 5 m from the
antenna.
However, no restrictions are required when the antenna radome is installed
at least 2 m above the highest point accessible to passengers.
Authorized personnel should not be near the antenna for periods of more
than 1 hour per day without switching off the RF transmitter.