Future satellite communication systems proposed use geosynchronous (GEO) satellites, medium earth orbit (MEO), and low earth orbit (LEO) constellations. Most of the next generation satellite systems will use fast packet switching with onboard processing to provide full two-way services to and from earth stations. One of the major service drivers is a high data rate internet access carried over ...

In the near future low earth orbit (LEO) satellite communication networks will partially substitute for fixed terrestrial multimedia networks especially in sparsely populated areas. Unlike fixed terrestrial networks, ongoing calls may be dropped if satellite channels are shadowed. Therefore, in most LEO satellite communication networks more than one satellite need to be simultaneously visible i...

A satellite, in its orbit, is affected by perturbing forces, such as atmospheric drag, solar radiation pressure, Earth oblateness, and gravity of the celestial masses (other than the Earth). In this paper, the effects of these forces on the trajectories of different types of LEO satellites and a sample satellite (Z-SAT) are discussed. A few analyses are done on these orbits and the relevant res...

1 0-7803-7651-X/03/$17.00 © 2003 IEEE 2 IEEEAC paper #1197, Updated December 10, 2002 Abstract—Proposed satellite constellation networks, based on Geostationary Earth Orbit (GEO) satellites, Medium Earth Orbit (MEO), and Low Earth Orbit (LEO) systems, will be required to transport IP traffic and to provide quality of service (QoS). This paper proposes a new Diffserv-based scheme of IP bandwidth...

The area accessible from a spaceborne imaging radar, e.g. a synthetic aperture radar (SAR), generally increases with the elevation of the satellite while the map coverage rate is a more complicated function of platform velocity and beam agility. The coverage of a low Earth orbit (LEO) satellite is basically given by the ground velocity times the relatively narrow swath width. The instantaneousl...

The challenge of future mobile multimedia networks is to provide worldwide tetherless communication services. Low Earth Orbit-Mobile Satellite Systems (LEO-MSSs) will play a significant role by filling the coverage gaps of future generation terrestrial cellular networks. This lecture presents research results on demand-assignment Medium Access Control (MAC) schemes able to share efficiently LEO...

Low Earth Orbit (LEO) satellites are used for public networking and for scientific purposes. Communication via satellite begins when the satellite is positioned in its orbital position. Ground stations can communicate with LEO satellites only when the satellite is in their visibility region. The duration of the visibility and the communication vary for each LEO satellite pass over the station, ...

Based on the study of HLA (High Level Architecture) and OPNET-HLA interface, the dynamic control of simulation process and the real-time update of simulation for LEO (Low-Earth-Orbit) satellite communication system were achieved on multiple computers. In the distributed interactive simulation, a satellite’s location is controlled, then the end-to-end delay time and the routing table of Iridium ...

Space is an unforgiving environment – one of harshest known to mankind. Yet, space is far less understood than other service environments in which DOD systems operate. It has been known to limit the useful life of satellites, with 20 to 25% of all mission failures being attributed to the effects of the space environment.[1] Since access to space is so costly, materials and components must funct...

Abstract The role of N 2 in the upper atmosphere on atomic oxygen (AO)-induced erosion polyimide low Earth orbit (LEO) and sub-LEO is investigated through ground-based experiments flight data. experiment performed by adding an Ar beam at same collision energy as undecomposed O component AO formed laser detonation to simulate physical effect simultaneous sub-LEO. added dual-pulsed supersonic val...