Inmarsat is the pioneer of global mobile satellite communications and delivers broadband communications solutions to land, maritime and aeronautical users around the globe. Inmarsat is an international satellite communications system that currently provides voice and data services to over 25,000 mobile users on ships, land vehicles, and aircraft.  

Inmarsat is a world-leading provider of global mobile communications via satellite. Inmarsat is an internationally owned co-operative of 85 member countries that provides mobile satellite communications world-wide. It is headquartered in London and has a regional office inDubai, serving the Middle East and Africa, and Singapore servingthe Asia Pacific region.  

Their technology is based on geo-stationary satellite technology which, because of satellite height, requires high-power terrestrial terminals and highly directional dish antennae which must be accurately pointed to the satellite at all times. 

Inmarsat Ltd has a portfolio of mobile satellite solutions, including voice, fax, intranet and Internet access and other data services. They have 25 years' experience in designing, implementing and operating satellite networks. Inmarsat Ltd is also supported by partners in the fields of equipment manufacture, software provision and systems integration.  

Inmarsat operates seven satellites, including the first three of the third-generation Inmarsat 3 series and one Inmarsat2 satellite. They own and operate the world's most advanced fleet of commercial mobile communications spacecraft, flying in geostationary orbit, 35,786km (22,240 statute miles) above the Earth.  

At the end of December 2003, approximately 290,000 terminals were registered to access Inmarsat Ltd's services. End-users can dial into the international telephone network and send data over the Internet at any time, from anywhere, simply by connecting to an Inmarsat satellite. It is important to note that Inmarsat is a commercial system; in most cases individual users are responsible for charges incurred through use of the system. Inmarsat charges range from 6-10 dollars per minute depending on the time of day the system is used.   

Through a linkage with the shipboard computer network, it is possible to send and receive E-mail via Inmarsat. Users will be recharged at a later date in proportion to the volume of data they transferred via Inmarsat. The Inmarsat system consists of three components: (1) the space segment and its support structure; (2) gateway earth stations for maritime, land, and aeronautical mobile satellite services(respectively MMSS, LMSS and AMSS); and (3) mobile terminals of various classes suitable for operation on all kinds of vehicles. The first series of satellites used by Inmarsat, starting in 1982, was leased from several sources: COMSAT (MARISAT), ESA (MARECS), and INTELSAT (ISV-MCP), MARISAT and MARECS being precursor demonstration services and the MCP being a maritime communications package on some INTELSAT Vs. The two most heavily used systems are the sound powered phone and the Navy style intercom. The sound powered satellite phone is very desirable aboard ship as it continues to function under all operating conditions and can be relied on during times of power outage.

A number of spaces are equipped with ordinary telephones which can be used to call other spaces within the ship or to call out from the ship. The ship's telephone system is also linked to the Inmarsat system. From any telephone on the ship one can direct dial any other telephone in the world.