If a secure connection is important, this technology is the first choice. A satellite telephone provides a connection for voice and / or data for communication in both directions. The connection is made via satellites.
So theoretically anywhere in the world and even in areas without a terrestrial cellular connection, calls can be made, SMS sent and position information transmitted.
The satellite forwards the incoming call to an earth station, which feeds the call into the public telephone network. Some of these devices have an "SOS button" that sends an emergency call, others have the option of counter-speaking as with radio devices. Some satellite telephones also allow the device to be "tracked", i.e. the temporary or continuous retrieval of the position. The satellite telephones are each linked to a satellite operator. Thus, the telephones cannot be used with satellite communication systems from different operators. With the purchase of a terminal, a satellite communication system is also selected. For this reason, before selecting the end device, its performance and the prices of the operator should be compared.