COBHAM Sea Tel Tracker 6000, Руководство по установке

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Site Survey – Land Based Sea Tel Tracker 6000
2. Site Survey – Land Based
There are three objective of the site survey. The first is to find the best place to mount the antenna and the
BDE. The second is to identify the length and routing of the cables and any other items or materials that are
required to install the system. The third is to identify any other issues that must be resolved before or during
the installation.
2.1. Site Selection
The radome assembly should be installed on a shore based concrete pad, where:
 The antenna has a clear line-of-sight to view as much of the sky (horizon to zenith at all
bearings) as is practical.
 S-Band (10cm) Radars - The ADE should be mounted more than 4 meters/12 feet from an S-
band Radar.
 The ADE should not be mounted on the same plane as the radar, so that it is not directly in the
radar beam path.
 The ADE should be mounted more than 2.5 meters/8 feet from any high power MF/HF antennas
(<400W).
 The ADE should be mounted more than 4 meters/12 feet from any high power MF/HF antennas
(1000W).
 The ADE should also be mounted more than 4 meters/12 feet from any short range (VHF/UHF)
antennae.
 The ADE should be mounted more than 2.5 meters/8 feet away from any L-band satellite
antenna.
 The ADE should be mounted more than 3 meters/10 feet away from any magnetic compass
installations.
 The ADE should be mounted more than 2.5 meters/8 feet away from any GPS receiver antennae.
 Another consideration for any satellite antenna mounting is multi-path signals (reflection of the
satellite signal off of nearby surfaces arriving out of phase with the direct signal from the
satellite) to the antenna.
 The ADE and the BDE should be positioned as close to one another as possible. This is necessary
to reduce the losses associated with long cable runs.
 The mounting location far enough away from surrounding buildings, towers, cranes or other
structures will also cause significant degradation of the signal when in direct line-of-sight between
the antenna and the LEO satellite it is tracking.
If these conditions cannot be entirely satisfied, the site selection will inevitably be a “best”
compromise between the various considerations.
2.2. Antenna Shadowing (Blockage) and RF Interference
At the transmission frequencies of this satellite antenna system, any substantial structures in the way
of the beam path will cause significant degradation of the signal. Care should be taken to locate the
ADE so that it has direct line-of-sight with the satellite without any structures in the beam path
through the full 360 degrees of ships turn, or 360 degrees around the antenna. Wire rope stays,
lifelines, small diameter handrails and other accessories may pass through the beam path in limited
numbers; however, even these relatively insignificant shadows can produce measurable signal loss at
these frequencies.
Surrounding buildings, towers, cranes or other structures will also cause significant degradation of the
signal when in direct line-of-sight between the antenna and the LEO satellite it is tracking.
2‐1
EAR Controlled - ECCN EAR99