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Communications satellites have been around for more than 50 years, and they are often the only way to communicate with remote parts of the world. Considering 70% of the planet is covered by oceans, it's easy to see how life would be very different had satellite connectivity not become both practical and affordable.
Satellite connectivity has also gone broadband in recent years -- although, its performance doesn't yet match that of contemporary landlines. But in situations where satellite-based networking may be the only option for those without access to terrestrial wired or wireless services, the compromises involved can be more than tolerable.
Typical satellite applications include earth resources management; remote sensing for environmental, military or intelligence purposes; voice and video communications; and good old internet and web access. The key variables to consider are mobility -- not all satellite stations are mobile -- required bandwidth and cost, and, occasionally, regulatory and political considerations. In general, though, enough satellite services are available in most parts of the world to assure a solution with the right combination of elements exists. Satellite connectivity is also ideal for many broadcasting applications, as customers of such services at DirecTV and SiriusXM already know.
Bright, shiny objects in the sky
Most communications satellites are geosynchronous, meaning they are parked in an orbit above the equator at an altitude -- 22,500 miles -- synchronized with the rotation of the earth below. They thus appear resident in the same location in the sky at all times. The downside, however, is the distance involved dictates a round-trip delay (latency) of a bit more than a half-second, which is enough to often cause frustration in those trying to communicate via voice, as well as for those looking for snappy internet responsiveness.
Lower-orbit options are also available, but usually with lower net throughput and, often, higher costs. Low-earth-orbit satellites, however, do offer the option of handset-sized terminals, which adds to convenience.
The costs of any satellite system will almost always be -- often significantly -- higher than terrestrial services, for both terminals and service; it isn't cheap to build, orbit and operate a satellite, and the economics often only make sense because there is no option other than not communicating at all. Services costs vary, so shopping around is essential.
While some firms have had visions of constellations of low-orbit communications satellites offering universal availability at landline prices, such has not yet come to pass -- and given the enormous costs of satellite-based services, it's doubtful that such ever will. Satellite networking will thus continue to be limited to specific military, government and associated situations. Still, it's available -- again, almost everywhere -- for a price.
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