COBHAM SAILOR 60 GX, Installation Manual

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Site preparation
3-4 Chapter 3: Installation 98-148248-C
Cobham SATCOM recommends that the radome should NOT be modified or changed to
another type. Exchanging or modifying the radome will not void the general warranty for
material and workmanship etc. but the performance cannot be guaranteed, and the satellite
operator approvals will not be valid.
3.2.2 Obstructions (ADU shadowing)
The ADU is stabilized in 3-axis (plus skew) and can be used in environments with elevations
of -28° to + 120°f to allow for continuous pointing even in heavy sea conditions. The ADU
beam is approximately m in diameter for the first 30 m from the ADU. Beyond 30 m the
beam gradually widens so that it is approximately 5 m in diameter at 100 m distance. This
beam expansion continues with increasing distance. Any obstructions, such as masts,
funnels, bridge house etc. within this field can cause signal degradation or signal loss.
For optimum performance adhere to the following guidelines:
1. Place the ADU so that it has as much free line-of-sight as possible without any
structures in the beam through one full 360 degrees turn of the vessel.
2. Do not place the ADU close to large objects that may block the signal.
3. Elevate the ADU by mounting it on a mast or on a mounting pedestal on a deck or deck
house top to avoid obstruction.
Note
Note that due to the short wavelength at Ka band and the
narrow beam width of the ADU even a
6 mm steel wire
placed within 50 m
inside the beam can causes signal
degradation.
Figure 3-1: Signal degradation because of obstructing objects