Thrane&Thrane TT-3064A, Руководство пользователя

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Introduction
15Oct99
Page 3
1 1 II
NTRODUCTION NTRODUCTION
This manual describes the Capsat
®
Telephone.
The Capsat
®
Telephone is a mobile Inmarsat-phone mini-M terminal which provides access
to international telephone, facsimile and data networks.
SS
ATELLITE ATELLITE
T T
ELEPHONE ELEPHONE
C C
OMMUNICATION OMMUNICATION
Operating the Capsat
®
Telephone is much the same as making direct international telephone
calls from an ordinary telephone.
The difference is that the Capsat
®
Telephone communicates directly with a satellite and
therefore does not rely on a local telephone operator to route the call to the desired
destination. Instead, the calls to/from the satellite are routed by designated Land Earth
Stations (LESs) which also communicates with the same satellite as the telephone terminal.
The necessary requirements to operate a satellite telephone is that
a)
the terminal is registered by a service provider (i.e. payment arrangements).
b) the location where the telephone is located is covered by a satellite, and
c) there is a free line of sight from the antenna of the terminals to the satellite.
The satellite system used by the Capsat ® Telephone is operated by the international
organisation, Inmarsat. The system consists of four satellites which combined guarantee
world-wide coverage (see appendix B for coverage maps).
When working with the Inmarsat-phone mini-M system, the following abbreviations are often
used:
MES Mobile Earth Station.
This is the name that Inmarsat uses for terminals.
E.g. the Capsat
® Telephone is a MES. Mobile refers to the fact that the terminals are re-
locatable.
Earth Station is a satellite communication term.
LES Land Earth Station.
The LES is located at the "other" end of the MES's satellite link. The LES connects to the
local telephone networks and manages calls to and from the MES.
NCS Network Co-ordination Station.
The NCS is responsible for assigning communication channels to the MESs. In case of
NCS failure the MESs will switch to "Stand-Alone" mode. In Stand-Alone mode
designated LESs in each ocean region will act as NCS.