In 2005 the (F1) and (F2) of Inmarsat’s recent series of satellites was launched known as the “I4” satellites. The third and final satellite (F3) was launched on August 18, 2008. These are the largest commercial satellites ever launched. Each satellite has a global beam, 228 narrow spot beams and 19 regional spot beams.
Global beam coverage is a single global beam that covers one third of the earth’s service excluding the poles.
Narrow spot beams overlap creating a coverage pattern. The Narrow spot beams provide Inmarsat’s broadband services including the BGAN service.
Wide spot beams also are overlapping providing most of the areas interested to Inmarsat’s customers which are smaller areas compared to the global beam coverage.Network Performance
Most of Inmarsat’s networks provide multiple services including voice, data and fax satellite service. Their existing and evolved services are offered through land earth stations not owned or operated by Inmarsat, but through companies with a commercial agreement with Inmarsat. IP based services are provided by distribution partners. The satellite gateways are owned by Inmarsat.
IP based services include Broadband Global Area Networks (BGAN). They use the new I-4 satellites offering a shared channel IP packet switched service up to 492 kbits and streaming IP service from 32 to 256 kbits. Some terminals offer mobile ISDN service at 64 Kbits while also offering voice service at 4.8 kbits.
Also part of the IP service of the BGAN family is they Fleet Broadband offering similar services to the BGAN. Fleet Broadband provides voice and data services to Maritime users.
Serving aeronautical users with BGAN service is the Swift Broadband designed for military, commercial and private aircraft.
Existing and Evolved services including the following:
Aeronautical providing voice, data and fax services for aircraft: There are three terminals, Aero-L used for packet data, Aero-h for voice, fax and data up to 9600 bits, and Aero-I for low quality voice and fax/data up to 2400 bits.
Inmarsat B provides voice and fax/data services at 9.6 kbits as well as high speed data at 56, 64, and 128 kbits.
Inmarsat M providing voice and fax/data services at 2.4 kbits.
Inmarsat Mini M using Inmarsat’s zonal ray technology providing voice and fax/data at 2.4 kbits.
GAN (Global Area network) providing voice, fax/data at 2.4 kbits, ISDN at 64 kbits and IP packet switched data at 64 kbits.
Fleet providing services similar to the GAN uses the Inmarsat Fleet77, Inmarsat Fleet55 and Inmarsat Fleet33 hardware.
Swift 64 providing services similar to the GAN for using on aircraft.
MPDS (Mobile Packet Data) where several users share a 64kb/s carrier which is a service sold with the GAN family of terminals.
Inmarsat’s handheld satellite phone called the Isatphone provides satellite voice service at 4.8 kbits and fax/data service at 2.4 kbits. The IsatPhone service covers Europe, Asia, Africa, and Western Australia. IsatPhone service will be available in the U.S. in 2009.