COBHAM SEA TEL 9711IMA-70, Руководство по установке

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9711IMA-70 Introduction
1-3
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.
1.7. 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
1.8. 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.
1.9. FCC Compliance
This antenna system, with current software, contain FCC compliant supervisory software to continuously monitor
the pedestal pointing error. This supervisory software will trip an error flag, which will automatically cease
transmission within 100 milliseconds, if the pointing error should exceed 0.5 degrees. Transmission will not
resume until the pointing error drops below 0.2 degrees.
To be compliant with these FCC requirements, the “Transmit Mute” output of the Sea Tel below
decks controller must be connected to the “Mute Input” of the satellite modem via serial or via an
Ethernet connection to the modem.
EAR Controlled - ECCN EAR99