Low EarthOrbit (LEO) is the orbit of low-flying, fast-orbiting telecommunications satellites that orbit the Earth in circular paths. The flight altitude of Low Earth Orbit satellites is between 500 km and 1,500 km, and the Earth's orbital period is between 1.5 h and 2.5 h. This corresponds to a speed of approximately 27,000 km/h.
Low Earth Orbiter satellites have the advantages of short signal propagation time between ground station and LEO satellite and can therefore be used for voice communication and satellite Internet. The low transmission power with which LEO satellites can be reached from Earth should also be emphasized.
Satellite services based on low-orbit satellites are called LEO-SAT, and more than a dozen global satellite service operators offer such services. In addition to voice services, satellite Internet also provides data services, multimedia services and video services with transmission rates of up to 64 Mbps.
Some earlier projects from the turn of the century, such as Teledesic or Skybridge, have already been discontinued. Other satellite Internet projects are under construction. These include Starlink with over 40,000 LEO satellites, OneWeb with over 6,000, and Amazon 's Kuiper project with over 3,000 LEO satellites, to name a few.