China
Africa
Explore chapters and articles related to this topic
Defense Information, Communication, and Space Technology
Published in Anna M. Doro-on, Handbook of Systems Engineering and Risk Management in Control Systems, Communication, Space Technology, Missile, Security and Defense Operations, 2023
Medium earth orbit (MEO; also known as intermediate circular orbit) refers to near-circular orbits with altitudes in the range of about 5000 and 25,000 km above the surface. The orbit period may vary from about 3 to 12 hours (Kramer 2002). The GLONASS (stands for Globalnaya Navigazionnaya Sputnikovaya Sistema; Russia’s GPS) and GPS constellations are MEO examples with periods of 11.25 and 12 hours, respectively, others are LAGEOS (stands for Laser Geodynamics Satellite or Laser Geometric Environmental Observation Survey) with about 6000 km altitude, and the Inmarsat-P (communication satellite) series with altitudes of 10,350 km (Kramer 2002).
Foundations of electromagnetism
Published in Riadh Habash, BioElectroMagnetics, 2020
In addition to the current fleet of geostationary earth orbit (GEO) satellites, the next generation of medium earth orbit (MEO) and low earth orbit (LEO) satellite systems will be highly flexible and up to ten times more powerful than the current constellations. GEO is about 35,800 km above the equator, MEO is between 5,000–12,000 km above the earth, and LEO is between 500–1,500 km above the earth, so the delay is very small and the losses are small. A single GEO satellite can provide communications downlinks over wide areas, such as whole countries or continents, including to areas with no terrestrial connections. Constellations of MEO and LEO satellites can deliver high-capacity services to localized areas with low latency. Several companies (for example, SpaceX, OnWeb, Boing, Spir Global, Telesat) are proposing to provide 5G from space utilizing a combined 20,000 satellites in MEO and LEO that will blanket the earth with powerful, focused, and steerable beams.
Satellite Optical Imagery
Published in Victor Raizer, Optical Remote Sensing of Ocean Hydrodynamics, 2019
Medium low Earth orbit (MEO) takes place at region of space around Earth above low Earth orbit with an altitude of 2,000 km (1,243 mi) above sea level and below GEO with an altitude of 35,786 km (22,236 mi) above sea level. The orbital periods of MEO satellites range from 2 to 12 h. MEO is particularly suited for constellations of satellites mainly used for navigation, communication, and space environment science. A satellite in this orbit travels at approximately 7.3 km/s.
Satellite delivery of high-accuracy GNSS precise point positioning service: an overview for Australia
Published in Journal of Spatial Science, 2019
MEO satellites, such as navigation satellites, orbit the Earth at an altitude above that of a LEO and below that of a GEO. For example, GPS satellites have an altitude of approximately 20,200 km, which gives an orbital period of almost 12 h. Like HEO, the benefit of using MEO satellites for transmission is that they provide better coverage in urban canyons and in extreme latitudes as compared to GEO satellites.