Hughes Thuraya Orion, Installation Manual

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
The Antenna - Above Deck Unit (ADU) 17
Chapter 3
Above Deck Unit (ADU) Install
The antenna unit (ADU) is composed of the antenna element, high-power and low-
noise amplifier systems, and a mechanical tracking system housed in the radome.
The ADU is a SpaceCom HN321 3-axis antenna intended for maritime use.
Connection to the ADU is made by an N connector. The single coaxial cable carries
L-band RX and TX, power, and control information.
Physical dimensions

ADU: Size: 319.5mm x 277mm
Weight: 4kg
Figure 3-1. ADU - Maritime Antenna
Antenna cable lengths
and types
The Hughes BDU has an automatic cable calibration feature that determines the loss
of the cable. The RF cable that comes standard in the terminal kit is 25 meters long. If
a different cable is required for the installation, the end-to-end RF loss needs to be
10dB +0dB/-8dB at 1.6GHz and the cable must be 50 Ohm impedance.
Note: The installer is responsible for choosing the proper type of cable for the length
required in order to meet the loss requirement.