Satellites in low Earth orbit (LEO, below ) and medium Earth orbit (MEO, between ) are less common, operate at lower altitudes, and are not fixed in their position above the Earth. Because of their lower altitude, more satellites and launch vehicles are needed to cover a geographical area . This makes the initial required investment very large which initially caused OneWeb and Iridium to declare bankruptcy. However, their lower altitudes allow lower latencies and higher speeds which make real-time interactive Internet applications more feasible. LEO systems include Globalstar, Starlink, OneWeb and Iridium. The O3b MEO constellation is a medium Earth-orbit system with a latency of 125 ms. COMMStellation™ is a LEO system, scheduled for launch in 2015, that is expected to have a latency of just 7 ms.
Satellites in low Earth orbit (LEO, below ) and medium Earth orbit (MEO, between ) are less common, operate at lower altitudes, and are not fixed in their position above the Earth. Because of their lower altitude, more satellites and launch vehicles are needed for worldwide coverage . This makes the initial required investment very large which initially caused OneWeb and Iridium to declare bankruptcy. However, their lower altitudes allow lower latencies and higher speeds which make real-time interactive Internet applications more feasible. LEO systems include Globalstar, Starlink, OneWeb and Iridium. The O3b MEO constellation is a medium Earth-orbit system with a latency of 125 ms. COMMStellation™ is a LEO system, scheduled for launch in 2015, that is expected to have a latency of just 7 ms.
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to cover a geographical area
for worldwide coverage