Study on Circular MEO Satellite Constellation for Global Mobile Communication
- Paper number
IAC-08.B2.1.4
- Author
Dr. Hongyan Xu, China Academy of Space Technology (CAST), China
- Coauthor
Mr. Cao Guixing, China Academy of Space Technology (CAST), China
- Year
2008
- Abstract
The choice of satellite constellation is usually a compromise of all kinds technical and non-technical factors. In early study of satellite constellation and systems, GEO satellite systems were given bigger weight due to the inability of inter satellite link, network forming and etc. And with the development of cell communication, multiple access, dot beam antenna, frequency multiplexing and other techniques, the emphasis turns to LEO satellite constellations, which become hot on account of the higher estimation on the accepted time delay in communication. MEO constellation was then paid less attention and without in-depth study, despite it might be the cheapest one with fewer satellites, lower time delay, and easier network and handover control. With an overview of the InmarSat-P, Odyssey, MAGSS-14 and other similar systems, circular orbit MEO constellations are studied and compared in detail with the ground elevation of 10º. First, several well-known satellite constellations with single coverage globally were summarized including polar orbit constellation, near polar orbit constellation, optimized Walker’s Delta constellation, and optimized Ballard’s Rosette constellation. Then, two kinds of circular MEO constellation are put forward. The first one is a constellation with m satellites in equator orbit and n satellites in polar orbit. With the calculation of the width of the coverage belt in the equator orbit, and the minimum latitude of the polar cap, a "6+4" constellation is advanced with 6 satellites in the equator orbit and 4 in the polar orbit, the coverage of which is analyzed and the amount and location of the earth station are studied and with the inter satellite link. On the basis the "6+4" constellation is improved to "5+4", which is analyzed correspondingly. The second one is a circular MEO constellation with same ground track. The constellations with 10 or 9 or 8 satellites are studied respectively on the coverage on the ground and the coverage on the space, the location of the earth station, and the inter satellite link. Finally the two kinds of satellite constellation are compared in the average angle of the latitude elevation, the minimum average angle of the latitude elevation, and the coverage rate globally. The conclusion is drawn with comparison between the two kinds of satellite constellations that the "6+4" circular MEO constellation is the best one in general and the constellations with same ground track are better with coverage in the middle latitude in south and north hemisphere.- Abstract document
- Manuscript document
(absent)