How do satellite phones work?

Although it is possible to make telephone contact through a landline or mobile phone from almost anywhere in the world, there are certain areas where a satellite phone is the only method of communication.

Unlike mobile phones which use localised phone masts to connect calls, a call made from a sat phone is sent through a satellite constellation until it reaches the nearest satellite gateway on the ground. It is then routed through traditional voice networks to reach its destination.

A call made from one satellite phone to another will be completely routed through satellite constellations to ensure that the call is not affected by any technical difficulties on the ground. This is why satellite phones are essential for communication during disasters such as earthquakes and hurricanes where traditional lines of communication can be destroyed.

Satellite phones rely on a clear view of the satellite to make a call so it is important to ensure that the phones signal is not obstructed by trees, hills, mountains, buildings or other similar structures or geographical features in close proximity.

When choosing a satellite phone you may want to consider the type of satellites that your handset will use. Iridium and Globalstar use LEO (Low Earth Orbiting) satellites whereas Inmarsat and Thuraya use geosynchronous satellites which orbit at a much higher altitude. The higher a satellite orbits the more noticeable the latency or delay in call connection and transmission.