Sailor 100, Руководство по установке

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Site preparation
3-12 Chapter 3: Installation 98-136280-B
3.2.6 Interference
The ADU must be mounted as far away as possible from the ship’s radar and high
power radio transmitters, because they may compromise the ADU performance. RF
emission from radars might actually damage the ADU.
Radar
It is difficult to give exact guidelines for the minimum distance between a radar and the
ADU because radar power, radiation pattern, frequency and pulse length/shape vary
from radar to radar. Further, the ADU is typically placed in the near field of the radar
ADU and reflections from masts, decks and other items in the vicinity of the radar are
different from ship to ship.
However, it is possible to give a few guidelines. Since a radar radiates a fan beam with
a horizontal beam width of a few degrees and a vertical beam width of up to +/- 15°,
the worst interference can be avoided by mounting the ADU at a different level –
meaning that the ADU is installed minimum 15° above or below the radar antenna. Due
to near field effects the benefit of this vertical separation could be reduced at short
distances between radar antenna and the SAILOR 100 Satellite TV ADU. Therefore it is
recommended to ensure as much vertical separation as possible when the SAILOR 100
Satellite TV ADU has to be placed close to a radar antenna.
Note
Do not place the ADU close to interfering signal sources.
For allowed distances to transmitters see Figure 3-11:
Recommended distance to transmitters (m) for frequencies
below 1000 MHz
on page 3-14. We recommend testing the
total system by operating all equipment simultaneously
and verifying that there is no interference.
Figure 3-10: Interference with the vessel’s radar
Min. 15°
Min. 15°
Radar
SAILOR100IM.book Page 12 Friday, January 18, 2013 10:28 AM