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A 'satellite telephone', 'satellite phone', or 'satphone' is a mobile phone that communicates directly with orbiting communications satellites. Depending on the architecture of a particular system, coverage may include the entire Earth, or only specific regions.

The mobile equipment, also known as a terminal or earth station, varies widely. A satellite phone handset has a size and weight comparable to that of a late 1980s or early 1990s mobile phone, but usually with a large retractable antenna. These are popular on expeditions into remote areas where terrestrial cellular service is unavailable.
A fixed installation, such as used shipboard, may include large, rugged, rack-mounted electronics, and a steerable microwave antenna on the mast that automatically tracks the overhead satellites.
Satellite phones are usually issued with numbers in a special country calling code. For example, Inmarsat satellite phones are issued with codes +870 through +874, while Iridium satellite phones are issued with codes +881 6 and +881 7. Some satellite phones are issued with ordinary phone numbers, such as Globalstar satellite phones issued with U.S. telephone numbers.

Contents

Geostationary services

Low Earth orbit

Calling costs

Satellite phones in popular culture

References

Geostationary services

Some satellite phones use satellites in geostationary orbit. These systems can maintain near-continuous global coverage with only three or four satellites, reducing the launch costs. The major satellite systems in civilian use are Inmarsat and Thuraya.
The disadvantage of geostationary satellite systems is that because the satellite is so far away (approx. 22,000 miles), a comparatively large antenna system is required for signal transmission and reception. The physical phone system must therefore be quite large compared to current terrestrial mobile phones. They are similar in size to terrestrial mobile phones of the past.
One serious disadvantage of satellite phones is that the handheld units need a clear view of the sky. Thus they will not work inside buildings, cars or boats. External antennas are required for these uses.

Low Earth orbit

LEO telephones utilizes LEO (low Earth orbit) satellite technology. The advantages include providing worldwide wireless coverage with no gaps. Newer satellite phones tend to be LEOs. LEO satellites orbit the earth at high speed, low altitude orbits with an orbital time of 70–90 minutes, an altitude of 640 to 1120 kilometres (400 to 700 miles), and provide coverage cells. Since the satellites are not geosynchronous, they must fly complete orbits and thus further guarantee complete coverage over every area by at least one satellite at all times. Blimps are being considered as an alternative to satellites.
The two deployed LEO satellite systems are Iridium and Globalstar. Customer numbers for both systems never matched the levels required to fund the large number of satellite launch costs, and both went into bankruptcy. They are now operated by new owners who bought the assets for a fraction of their original cost.
There are several models of satellite phones available.

Calling costs

The cost of making calls from a satellite phone is usually quite high, while calling them from landlines and regular mobile phones is extremely expensive. Rates from landlines and mobile phones range from $3 to $14 per minute with Iridium and INMARSAT being some of the most expensive networks to call. The receiver of the call pays nothing, unless they are being called via a special reverse-charge service.
Making calls between different satellite phone networks is also notoriously expensive with calling rates of up to $15 per minute.
Calls from satellite phones to landlines are usually around 80c to $1.50 per minute unless special offers are used. Such promotions are usually bound to a particular geographic area where traffic is low. Globalstar is currently offering unlimited calling plans until 2009 - something almost unheard of with satellite phones but their current network is highly unreliable and could be out of service sometime in 2008 ^[1].
All satellite phone networks have pre-paid plans, with vouchers ranging from $10 to $5000.

Satellite phones in popular culture

Satellite phones are said to be difficult to trace, making them a popular favorite for criminals. ^[2]

★ Within the film ''Jurassic Park III'', Paul Kirby lends his Globalstar satellite phone to mercenary M.B. Nash after a plane crash on Isla Sorna. A ''Spinosaurus'' eats Nash and the phone is later found in its feces.

★ The satellite phone was also used many times on the show ''Relic Hunter''. The main character, Sydney Fox, would use it to communicate back home when she found interesting relics.

★ Phones both identified as satellite phones and those that appear to be satellite phones are often used on the television drama ''24''.

★ A satellite phone appeared in the episode of ''Lost'' entitled "Catch-22".

★ Similar phones appear in the action film ''Miami Vice''.

★ The satellite phone is also used in the film-based video game .

★ A satellite phone is used several times in Die Hard 4

★ A satellite phone is used in the movie Jurassic Park 2, both by the Ingen operations(seen with a large dish) and by the Hammond researchers, when Ian Malcolm attempts to reach the boat because his daughter Kelly has snuck on the island without his permission.

★ A satellite phone is used in the TV show ''Alias'' as a plot device in the first season.

★ A satellite phone is used in the action film "Under Siege" to contact military officials.

★ A satellite phone is also used in the Anime Digimon Adventure: Children's Wargame. It was used by Izzy to connect his computer to the net after Infermon modified the NTT system.

★ A satellite phone is used in the movie "Blood Diamond" by the film's main character played by Leonardo DiCaprio.

References

1. http://www.sec.gov/Archives/edgar/data/1366868/000110465907007275/a07-3495_18k.htm
2. http://www.space.com/businesstechnology/technology/satellite_phones_030321.html