KVH Industries F33 Manuel D’Utilisation

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The Inmarsat Fleet Service 
Introduction 
2 Introduction 
2.1  The Inmarsat Fleet Service 
The Inmarsat Fleet service is based on 4 Geo-stationary 3
rd
 
generation satellites situated above the equator. Geo-
stationary means that the satellites are always located in 
the same position, i.e. they rotate at the same speed as 
that of the earth. Each satellite covers a certain area 
(footprint) and supports a number of powerful spot-beams 
making the service available in virtually all ocean regions 
on the earth between approximately 76°N and 76°S.  
The 4 Geo-Stationary Inmarsat Satellites 
The satellites are your connection to the worldwide 
networks, and they are managed by the Network Co-
ordination Stations (NCSs), run by Inmarsat. The primary 
functions of the NCSs are to constantly keep track of which 
terminals are logged on to the system, and assign a free 
channel whenever a call is made. 
A Land Earth Station (LES) is a gateway between the public 
network and the satellites. Different operators around the 
world run the various LES’s. 
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May 2005 
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