We developed a multimedia satellite network system based on the Internet protocol (IP) and personal computers. It enables collaborative distance education between outdoor and indoor environments. Integration of IP technologies and satellite communications enhances the flexibility of the network system. The satellite communication system enables us to communicate to and from outdoor environments...

This paper describes a program of experiments conducted by the CSHCN using ACTS. This program of three experiments commenced in 1992 and utilized the ACTS T1-VSAT terminal. The experiments were motivated by the commercial driver of low-cost receive-only satellite terminals that can operate in a hybrid network environment. The first experiment tested highly adaptive methods of satellite bandwidt...

Since the IETF “TCPSAT” Working Group was chartered in 1997, numerous issues with TCP over satellite have been addressed. Although the difficulties encountered are the same, it seems as though adaptive multimedia communication over satellite has been neglected. We identify the common problems, discuss their impact and introduce a method to deal with some of them — a protocol that queries router...

This paper proposes novel satellite-based wireless sensor networks (WSNs), which integrate the WSN with the cognitive satellite terrestrial network. Having the ability to provide seamless network access and alleviate the spectrum scarcity, cognitive satellite terrestrial networks are considered as a promising candidate for future wireless networks with emerging requirements of ubiquitous broadb...

nowadays, with the advent of new satellite services, the need for resource management in the emerging fifth generation satellite systems (5g-satellite) is inevitable. thus, to solve this problem, the bandwidth manager for resource reservation in satellite link is mandatory. on the other hand, due to limited resources, their resource management­ is essential. in order to resource management in 5...

Redundancy is a major concern to satellite communication amplifier systems. This paper examines the various types of redundant systems used in satellite communication systems from a system reliability viewpoint. To overcome the ambiguities involved with comparing MTBFs, the paper discusses amplifier reliability based on static reliability concepts. Both traditional switched redundant systems an...

There is a trend for mobile satellite system architectures aimed at the deployment of multi-satellite constellations in Non-Geostationary Earth Orbits (NGEOs). This allows the user terminals to be small size, low cost and having low power demand. In present and next generation satellite systems, CDMA has been proposed as the multiple access technique for a number of mobile satellite communicati...

Analysis of satellite-telemetry data mostly occurs long after it has been collected, due to the time and effort needed to collate and interpret such material. Delayed reporting reduces the usefulness of such data for nature conservation where timely information about animal movements is required. To counter this problem, we present a novel approach which combines automated analysis of satellite...

This paper presents a combination of Free Space Optic systems with WLAN and Satellite Communications to provide Video conferencing and data transfer for use in Civil Military Cooperation and disaster recovery applications. A modular communication system developed at TU Graz is described, which facilitates worldwide access to the Internet or any other network (depending on the particular applica...

This paper emphasises on the implementation of the flow control and resource allocation mechanisms of the Medium Access Control (MAC) layer of GPRS. Also, its design for adaptability to the satellite network has been considered. In addition, the two systems have been compared in terms of transmission-time, for different data sizes. The results obtained show a lot of promise for satellite based ...