Capsat TT-3080A User Manual page 15

Hardware interfaces Hardware interfaces
The mini-M voice mini-M voice service is only for voice and the voice
transmitted over the satellite is subject to a compression and
decompression process which makes it possible to reduce the
normally needed transmission bandwidth from 64 kbit/s into 2,4
kbit/s.
The mini-M fax mini-M fax service only supports fax transmission at 2,4
kbit/s. If a fax machine can transmit at 14400 bit/s by using the 3.1
kHz audio service, it may be cheaper to use this high speed
service instead of the mini-M fax service if the tariff of the 3.1 kHz
audio service is less than 14400/2400 times the mini-M fax tariff.
Of course the overall transmission time will be shorter at the
higher speed.
In fact the only difference between the high speed connections
made via the Global Area Network and via terrestrial digital
networks is the higher delay which is a result of the long distance
between the earth and the satellites (36.000 km). Certain
applications may have difficulties coping with this delay.
The mini-M data mini-M data service can only be used to transmit at 2,4
kbit/s. The same considerations as for fax transmission can be
done about tariffs and time.
Before a terminal can be used on the network it has to be
commissioned by one of the ISP's. In order to use the different
Global Area Network services it is necessary to have at least one
Inmarsat Mobile Number (IMN) for each of the services, which the
user wants to use. This number is the number to dial in order to
establish a connection to the Global Area Network terminal. If all
8 services should be available the terminal must thus have 8 IMN
numbers.
Calling a Global Area Network terminal is equal to making
international calls. If the satellite region/area is not known for the
terminal the "country" code for a terminal is 870.
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Description of the service Description of the service
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