Low earth orbit (LEO) satellite systems gained considerable interest in the past decade and were expected to be instrumental in future telecommunications systems. Nevertheless, the first two LEO satellite networks that are currently in operation have not come to fruition on account of the limited spectrum of services that they provide. In this context, future LEO satellite networks will be gear...

In this paper, we discuss on two important issues through the realization of global personal communication networks with low earth orbital (LEO) satellites. The first issue is the selection of an effective multiple access scheme which can utilize the limited spectrum allocated to these systems. In this way, we focus on the schemes based on spread spectrum techniques and explain their unique cha...

The Internet Engineering Task Force (IETF) is working on extending the traditional TCP/IP model for supporting multimedia and real-time applications on the Internet. Thus, new protocols have been developed such as the Resource Reservation Protocol (RSVP). At the same time, there has been a growing interest in using Low Earth Orbit (LEO) satellites. In the near future, when the Internet with mul...

in this paper, new features of satellite configuration, such as ip network  based infrastructure and separated signaling and media  are considered to propose a variety of satellite configurations in different orbits. because of their  different altitude in space such as low earth orbit(leo) and geostationary orbit (geo). a test bed used to test call setup delay in a one space link to process th...

In this paper we present a model to study the end-to-end delay performance of a satellite-ATM network. We describe a satellite-ATM network architecture. The architecture presents a trade-off between the on-board switching/processing features and the complexity of the satellite communication systems. The end-to-end delay of a connection passing through a satellite constellation consists of the t...

GPS radio occultation technique has been developed resulting from remote sensing applications in planetary atmospheric limb sounding pioneered by JPL and Stanford University in 1960s. Since the launch of the experimental satellite MicroLab1 on April 3 1995, the primary results from this Low Earth orbiter (LEO) satellite demonstrated potential scienti:c values and practical signi:cance of this i...

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...

Routing in Low-earth-orbit (LEO) satellite system involves the choice of inter-satellite links (ISLs) that connects two home satellites of the mobile terminals. We use a mesh model to formulate the LEO system and proposed 4 mesh-based algorithms. The objective is to minimize the new call blocking probability and the forced termination probability. Also, due to the dynamic topology of the LEO sy...

This paper describes the essential segments of a satellite based communication and asset management system. The Low Earth Orbit satellite used for such a system is the ORBCOMM low earth orbit (LEO) constellation. The architecture and network structure of the satellite system is described. The satellites themselves are very small and are launched using the Pegasus launch vehicle. This makes the ...

To reduce the sampling rate in global navigation satellite system (GNSS)-radio occultation receivers, it is essential to establish a suitable estimation of Doppler frequency from the received signal in the satellite onboard receiver. This receiver is usually located on low earth orbit satellite and receives GNSS satellites signal in the occultation situation. The occurred Doppler on the signal ...