Inmarsat

INMARSAT, also known as "Marisat" is a collection of geosynchronous telecommunications satellites used for telephone calls to aircraft, ships at sea and drilling platforms.

INMARSAT satellite phones use radio. They have a relatively large, wide high-gain antenna that must be aimed at the satellite. On most installations, the antenna is aimed automatically. The phones use speech coding to compress the voice digitally into a slow, 19.2 KBaud digital signal. The satellite is a repeater that repeats the digital signals at a different frequency to a ground station. The phone logs-on through the dumb satellite into the computerised ground station, and thereby connects to the public telephone services. Billing is started during the log-on process.

The telephone country codes for Inmarsat are:

• 871 Atlantic - East
• 872 Pacific
• 873 Indian Ocean
• 874 Atlantic - West

Calls to Inmarsat are some of the most expensive calls possible; the standard rate for most telephone companies is around $10.00 per minute (as of 2000).

External link

• http://www.inmarsat.org/