NEWSKY - A concept for NEtWorking the SKY for civil aeronautical communications

In this paper, an overview of the NEWSKY project is given. This project is funded by the European Commission within the 6th framework program and will start in January 2007. The NEWSKY project is a feasibility study to clarify if it is possible to establish a heterogeneous network for aeronautical communications which is capable to integrate different communications systems as well as different applications into a single global aeronautical network. The envisaged applications comprise not only air-traffic control and management but also airline and passenger communications

Converged Digital TV Services: The Role of Middleware and Future Directions of Interactive Television

The migration from analog to digital of the broadcasting technologies, already well consolidated for satellite systems, is becoming a reality also for terrestrial transmission. Digital Terrestrial Television (DTT) is also evolving to offer interactive services and a degree of flexibility which can be exploited to offer tailored applications to users which include, for instance interactivity, different levels of personalization, and innovative location-based, as well as context-aware, services. A clear example of this trend is given by the rising success of the Internet Protocol Television (IPTV) which allows for a degree of flexibility on offered services unknown to the traditional broadcasting systems. In this framework, several satellite operators are starting to launch IPTV services using direct satellite links, as well as some terrestrial internet service providers are offering digital TV channels embedded in the IP streaming over XDSL. Furthermore, IPTV services are likely to be broadcast also wirelessly, exploiting advanced broadband access technologies such asWiMAX, LTE, or LTEA. Last, but not least, TV and broadcast services for mobile users have also been deployed in many countries using DVBH and will be soon available on an even broader scale thanks to its satellite counterpart, DVB-SH. In the near future, a set of different technologies able to offer personalized and customized services to different classes of users are expected in the area of wireless broadcasting and convergence of technologies is auspicious. This concept entails different levels of convergence, namely, at terminal level (one device fits all), at service level (convergence of traditional fixed, mobile, and broadcast services), and at transport and network level with a common and standardized set of protocols and at access layer thanks to the harmonic coexistence of different radio technologies. This special issue aims to capture the state-of-the-art research work concerning the integration of DTT/Satellite/IPTV systems for the broadcasting of multimedia and interactive services

Méthode de modélisation non supervisée du canal satellite mobile par chaînes de Markov

Nous développons une méthode de modélisation de l'atténuation du canal satellite mobile par chaînes de Markov valable lorsque les conditions de propagation évoluent (fréquence de transmission, environnement). L'estimation des paramètres du modèle du canal satellite est non supervisée contrairement aux modèles existants. Pour cela, nous employons une méthode de type MCMC (Monte Carlo Markov Chain) à sauts réversibles qui permet d'évaluer la moyenne a posteriori des paramètres du modèle ainsi que la segmentation des observations. Un modèle du canal satellite mobile en bande Ku est obtenu pour un contexte urbain. Le modèle présente de très bonnes performances : les données expérimentales et simulées ont les mêmes caractéristiques statistiques

Advanced Fade Countermeasures for DVB-S2 Systems in Railway Scenarios

This paper deals with the analysis of advanced fade countermeasures for supporting DVB-S2 reception by mobile terminals mounted on high-speed trains. Recent market studies indicate this as a potential profitable market for satellite communications, provided that integration with wireless terrestrial networks can be implemented to bridge the satellite connectivity inside railway tunnels and large train stations. In turn, the satellite can typically offer the coverage of around 80% of the railway path with existing space infrastructure. This piece of work, representing the first step of a wider study, is focusing on the modifications which may be required in the DVB-S2 standard (to be employed in the forward link) in order to achieve reliable reception in a challenging environment such as the railway one. Modifications have been devised trying to minimize the impact on the existing air interface, standardized for fixed terminals

Networking the Sky

In this paper, an overview of the NEWSKY project is given. This project is funded by the European Commission within the 6th framework program and will start in January 2007. The NEWSKY project is a feasibility study to clarify if it is possible to establish a heterogeneous network for aeronautical communications which is capable to integrate different communications systems as well as different applications into a single global aeronautical net-work. The envisaged applications comprise not only air traffic control and management but also airline and passenger communications

Performance Assessment of an S-band Return Link for Messaging and Mobile Interactive Broadcasting

Within this paper we examine the performance in terms of aggregate MAC throughput of the return link of a messaging and mobile interactive broadcast system in S-band. More specifically, an analysis is done to investigate the impact of using two different air interfaces (synchronous and asynchronous access) within the same bandwidth on the instantaneous MAC throughput within one beam. All considerations take into account a realistic population density as well as the propagation envrionment and a linguistic pattern over Europe