Development of the past decade have confirmed that ATM technology has the potential of becoming the transport mechanism in many multimedia networks where high-speed traffic and Quality of Service guarantees must be provided. More recently, we have witnessed a surge of interest in Low Earth Orbiting (LEO) satellite networks with on-board ATM switches, which hold the promise of offering an econom...

Communication via satellite begins when the satellite is positioned in the desired orbital position. Ground stations can communicate with LEO (Low Earth Orbiting) satellites only when the satellite is in their visibility region. The visibility region is in fact the horizon plane. Because of natural barriers or too high buildings in urban areas, practical horizon plane differs from the ideal one...

the radar tracking is one of the best leo satellite tracking methods. while the tracking filters which are mostly linear, and them are not able to have a precise estimation of the objects with nonlinear motion dynamic such as satellite, we should use nonlinear filters. in this paper , firstly, we deal with the problem of the leo satellites motion path modeling according to the satellite motion ...

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...

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 ...

LEO satellite networks play a very important role in broadcasting Internet and connecting remote places at the time of natural calamities. Routing plays a very important role in faster data transfer by taking shortest path. LEO satellite networks are the preferred choice due to less propagation delay and packet loss as compared to GEO satellite network. The multimedia applications and live tran...

A three-dimensional ray tracing model with aiming algorithms for global positioning system (GPS) signal is proposed to make simulations conform to the realistic radio occultation (RO) signal propagation. The two aiming algorithms used in this study ensure the initial and end point ray trajectories are located in the prescribed region. In past studies, the ray tracing techniques applied to the R...

The tropospheric channel models developed for earth-GEO satellite links are not directly applicable for LEO satellites. In the absence of significant propagation datasets, reasonable models are developed for the simulation of earth-LEO link. This paper presents preliminary models for the simulation of the effect of turbulence on earth-LEO links.

Notwithstanding the limited commercial success of the first narrowband Low Earth Orbit (LEO) satellite systems, the interest of the scientific community in this type of systems has been revived on the basis of the current trend toward the migration to all IP-based services. LEO systems can play a pivotal role in providing services to areas where there is no substantial terrestrial infrastructur...

Low-Earth-Orbit satellite access network (LEO-SAN) can realize real-time and three-dimensional broadband on the earth anywhere any time. It has become a major development trend of Internet mobile communication networks, attracted more attention research from academia industry. LEO satellites achieve global coverage through giant constellations. Compared with medium- high-orbit satellites, have ...