COBHAM Sea Tel 9711-56 IMA C Band, Руководство по установке

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Sea Tel 9711-56 IMA Introduction
2-3
EAR Controlled - ECCN EAR99
When one antenna is blocked, its blockage output will command the arbitrator panel to switch services to the
modem from that antenna to the other antenna. The arbitrator panel provides a logic latch to prevent excess
switching when the ship heading is yawing, therefore, causing if the antenna to be repeatedly blocked –
unblocked – blocked.
2.6. Dual Network Arbitrator
Demand for greater bandwidth throughputs has led to service offerings that include access to multiple
networks from the vessel. To facilitate this a dual network (two modems) configuration is required.
This can be a single antenna – dual network configuration which allows the ship to access either of two
networks. One antenna system is installed and its’ ACU control output is connected to a dual network
arbitrator switch panel which is also connected to two satellite modems, and other below decks equipment if
provided.
A dual antenna – dual network configuration allows the ship to access to two networks simultaneously. Two
full antenna systems are installed and the two ACU control outputs are connected to a dual network arbitrator
switch panel which is also connected to two satellite modems, and other below decks equipment if provided.
Refer to the appropriate installation chapter for the model of the Sea Tel antenna systems that you will be
installing.
You will program the blockage zone(s) and optimize all other settings for best “on-satellite” performance for
each of the two Sea Tel antennas.
The following signals pass through the arbitrator to/from the ACUs and the Satellite Modem(s):
•
TX IF signal to the selected antenna from the selected Satellite Modem. 10 MHz reference is also
passed when provided by the modem.
•
RX IF from the selected antenna to the selected Satellite Modem.
•
Blockage control output from each ACU provides status of the antenna (available or blocked) to the
arbitrator.
•
GPS position - output from each antenna to the arbitrator. A setting in the in the arbitrator
determines which GPS signal gets routed to the satellite modem(s).
•
Receive Lock signal from the selected Satellite Modem(s) is routed to both ACUs to enable each of
the antennas to track the appropriate satellite/beam.
In single network mode, when one antenna is blocked, its blockage output will command the arbitrator panel
to switch services from that antenna to the other antenna. The arbitrator panel provides a logic latch to
prevent excess switching when the ship heading is yawing, therefore, causing either antenna to be repeatedly
blocked – unblocked – blocked.
In dual network mode, if one antenna becomes blocked there is no available antenna to switch to, so that
network will be out of service until the antenna is no longer blocked.
2.7. Automatic Beam Switching (ABS)
ABS is a method of communicating remotely via an overhead channel, or locally from the modem, to
reconfigure the ACU(s) to use a different beam on the same satellite or to use a different satellite. The
modems include commands which allow remotely setting all of the necessary parameters and to command
the targeting of the desired satellite
2.8. OpenAMIP™, ROAM or VACP
These each have standardized language incorporated into their (iDirect, Comtech & STM) modems which
communicates automatic beam switching settings from their options file to the Sea Tel ACU(s). This provides
the network a means of controlling automatic beam switching by the settings in the options file in the remote
modem.