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A Satellite Telephone
1. A satellite telephone, satellite phone, or satphone is a type of mobile phone that connects to orbiting satellites instead of terrestrial cell sites. They provide similar functionality to terrestrial mobile telephones: voice, short messaging service and low-bandwidth Internet access are supported through most systems. 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, varies widely.
2. Early satellite phone handsets had a size and weight comparable to that of a late-1980s or early-1990s mobile phone, but usually with a large retractable antenna. More recent satellite phones are similar in size to a regular mobile phone while some prototype satellite phones have no distinguishable difference from an ordinary smartphone. Satphones are popular on expeditions into remote areas where terrestrial cellular service is unavailable.
3. Since satellite phones are purpose-built for one particular network and cannot be switched to other networks, the price of handsets varies with network performance. If a satellite phone provider encounters trouble with its network, handset prices will fall, then increase once new satellites are launched. Similarly, handset prices will increase when calling rates are reduced.
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Satellite telephony is an advanced mobile telephony technology providing people with different advantageous opportunities improving the quality of their life, work and leisure.
People use satellite phones because of their perfect functionality, unusual design and large area coverage capacity being especially actual in remote areas where terrestrial cellular service is unavailable.
A satellite telephone connects to orbiting satellites instead of terrestrial cell sites but depending on its architecture it may cover the entire Earth, or only specific regions.
Satellite phones possess both some advantageous technical characteristics in comparison with cellular phones and some imperfections connected with dependence from their network provider.
