Furuno Felcom 82, Operator'S Manual

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1. INMARSAT-B SYSTEM
1.1 What is Inmarsat?
The International Maritime Satellite Organization (Inmarsat), founded in 1979, is
the international governing body for maritime satellite communication. Its purpose
is to provide global communications for ships, land mobile and aircraft, using
satellites to overcome the problems that exist with conventional radio
communications.
The Inmarsat system is made up of three major components: the space segment
provided by Inmarsat, the Land Earth Stations (LES) provided by Inmarsat
signatories, and Mobile Earth Stations (MES). The Operation Control Center
(OCC), located at Inmarsat headquarters in London, controls the overall system.
1.2 Geostationary Satellites
The type of satellites used for maritime communication are geostationary
satellites. Four satellites, one for each of four ocean regions, are placed in nearly
36,000 km-high 24-hour circular orbits rotating in synchronous with the earth,
providing mobile-to-land, land-to-mobile, and mobile-to-mobile communications.
The satellites remain fixed over a given place on the earth's equator, so an
Inmarsat subscriber is always within coverage of a satellite.
Speed: 11,070 km/h
Revolution: 23 hrs 56 min
35,860 km
72,752 km
Geostationary satellite
(35,860 km above Equator)
Earth
Geostationary satellites of the Inmarsat system