Ian Waugh - A Mariner\'s Guide to Marine Communications

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Inmarsat·M and Mini-M Installations

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The same rules regarding labelling antenna hazard areas apply to

Inmarsat-M/Mini-M as with other satellite antennas.

Equipment tests and checks

As with Inmarsat-AlB, power and data cable connections should
be checked, occasionally, to ensure that they are secure and not put
under bending strain, nor compressed. Your equipment user manual
will detail any operator tests/checks required for your particular
installation.

High bandwidth 'multi-channel' satellite networks

Some larger vessels (mainly cruise ships, and offshore installations
with high data and telecommunications needs) fit equipment that allows
a number of telephone, fax or data calls to take place at the same time.
'Multiplexed' Inmarsat-B/M terminals, into a single large antenna,
connect calls on an individual basis, on a single communications channel,
and close each channel on completion of each individual call.
Many larger vessels have installed a system that uses a high-
bandwidth communications circuit, capable of connecting a number of
calls simultaneously, and which is always open. The high-bandwidth,
multiplexed channel can handle different types of call at the same time -

174 THE NAUTICAL INSTITUTE