“Satellite phone work everywhere, so it shouldn’t matter, right?” Generally, that’s true: however, there are some very important considerations about satellite phone coverage.
You must have a clear view of the sky
Different satellite networks have different coverage
Some service plans have regional limitations
You Must Have a Clear View of the Sky
Satellite phones use a small radio signal to communicate with satellites that are miles above us. For example, Inmarsat satellites sit stationary about 20,000 miles above Earth over the equator; Iridium satellites fly overhead about 485 miles above Earth at about 17,000 miles per hour. Because the satellites are so far away, and satellite phones use about the same amount of power as a 1990’s cell phone, anything that blocks the radio signal from your antenna from reaching the satellite will stop your call from getting through.
In the movie “World War Z,” we watched with amusement as Brad Pitt’s wife called him from the inside of a metal aircraft carrier using her prop Iridium satellite phone. Spoiler: it was Hollywood magic. That call wouldn’t have worked in real life.
Different Satellite Networks Have Different Coverage Areas
Because satellite networks are quite different in how the satellites and earth stations work, coverage varies by satellite network.
Inmarsat Satellite Coverage
Because Inmarsat satellites are at the equator, you need a view of the sky over the equator to connect. In practice, this is not an issue, but if you’re blocked from that sky because you’re in a ravine or between skyscrapers, for example, your test call will not work.Inmarsat currently offers service across the entire Earth minus the poles, but they are expanding coverage.
Iridium Satellite Coverage
Iridium satellites are constantly moving, and you should be aware that if you have only a very limited view of the sky you will eventually have coverage, but you might not have it all the time.
Globalstar Satellite Coverage
The Globalstar system relies on many earth stations to pass along the satellite signal, so coverage is dependent on where the earth stations are.
Thuraya Satellite Coverage
Thuraya covers Europe, Africa, Asia and northern Australia but their satellites do not cover the Americas.
Additionally, some service plans offer different rates depending on where you are. If you bought a regional plan and you are not in that region, you may get unexpected charges or be blocked from certain services.