Satellite phone
A satellite phone connects for voice or data for satellite communication in both directions ready. The connection to the terminal ( telephone, " mobile " ) is via radio directly to a satellite. So theoretically can be made anywhere in the world and even in areas without terrestrial mobile coverage calls. The satellite passes the incoming call to an earth station on which connects the call in the public telephone network.
History of Satellite Phones
Starting at the end of the 1970s, satellites have been used for communication over long distances. The transmitting and receiving equipment of these systems, however, were very large and stationary. Only the International Maritime Satellite Organization ( Inmarsat ) introduced from 1982, a system for mobile devices ready, which was mainly used in maritime shipping. From 1989 the first units for land mobile use.
In the late 1980s, Canada took the opportunity to provide satellite phones large, sparsely populated areas with telecommunication without having to provide a sophisticated, ground-based infrastructure as the first country. Shortly thereafter, a similar system was launched in the United States. The satellites used in this case were on geostationary positions.
In 1985 Motorola developed the Iridium communications system, their satellites revolve the earth from pole to pole. This also allows the polar regions are covered, which are not served by the always stood above the equator geostationary satellites.
Through the establishment of networks with satellites in low earth orbit (LEO, MEO ), the distance between the satellite and the terminal was significantly reduced and thus the necessary transmission power can be reduced in the terminal. It is this generation of devices could be measured in weight and size to the recently established mobile phones, it has, however, can not be out of the market, because both the terminals and the connection fees of these networks it is much too expensive, and on the other entirely different conditions, such as z. B. unobstructed view of the sky are necessary. Meanwhile, could extremely powerful satellites reduce (eg, Thuraya ) in a geosynchronous / geostationary orbit, the size of the devices even further.
Meanwhile dare first provider balancing act " mobile phone and satellite phone ". One of the pioneers of this approach is the company Spot LLC, a subsidiary of the satellite operator Globalstar, has recently unveiled a device name " SPOT Connect". This makes possible satellite links over a normal, modern smartphone. This is made possible via a Bluetooth connection between the device and a commercially available smartphone and a mobile app that is installed on the phone.