Deep and frequent GPS signal fading due to strong ionospheric scintillation is major concern for aircraft navigation in the equatorial region during solar maximum periods. Deep signal fading can break a receiver’s carrier tracking lock on a satellite channel and the satellite cannot be used for position solution until a receiver reacquires the lost channel. Frequent signal fading also causes fr...

Broadband satellite access (BSA) systems can form an alternative path for the provision of Internet access in areas with poor network infrastructure. The DVB-RCS standard introduced the specifications of an interaction channel for two-way BSA networks. In this study, a new dynamic scheduling strategy for the interaction channel of GEO satellite networks is proposed, evaluated and compared with ...

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...

this study seeks to examine how a company can select the best intermediary for its marketing channels with minimum of criteria and time. a theoretical framework is proposed based on the most important tasks of intermediary and the criteria to measure them. there are four basic tasks and thirty criteria in three independent levels. subsequently, an exploratory case study in iranian food industry...

This paper proposes a method of improving reception of digital satellite broadcasting in a moving vehicle. According to some studies, the antennas used for mobile reception will be smaller in the next generation and reception will be more difficult because of a fading multipath channel with delays in a low carrier-to-noise ratio. Commonly used approaches to reduce the inter symbol interference ...

The quantum based systems could be the next steps in improving the satellite communication. The actual implementation of quantum cryptography systems would be invaluable, allowing for the first time the practical possibility of one-time-pad-encrypted, undecipherable communication, which will offer an essentially new degree of security in future satellite communications. They offer secure key di...

NASA is interested in using commercial satellites to provide broadband communications support for future space missions. In this paper, we describe a large-scale simulation model that we plan to use for detailed performance studies of critical parameters. We focus on the unique challenges we face and how we plan to use simulations to investigate: • the feasibility of using proposed commercial c...

Geostationary satellite networks are currently considered as one of the most promising broadband access network technology for narrowing the digital divide. Though technically attractive and cost effective, the provisioning of endto-end QoS services in satellite access remains largely undefined. In order to bridge this gap, the European SATIP6 project defines a complete QoS architecture involvi...