This paper presents a programmable measuring platform that integrates a powerful processing unit combining software and hardware modules with a set of powerful signal generation and analysis instruments for realizing realistic evaluations and measurements on receiver subunits and receiver prototypes. The test-bed exploits the telecommunication instruments in order to provide fully controlled ch...

Multi-user traffic prediction is an important issue in broadband satellite communications system. In view of multiple UTs (User Terminal) which are treated by a single ST (Satellite Terminal), a novel NMF-based (Nonnegative Matrix Factorization-based) multi-user traffic prediction method is proposed. Compared with previous prediction schemes, the new method can reduce computational complexity a...

The increasing use of world wide networking facilities for international information exchange and service provision demands for specific applications of machine translation (MT) tools which are beyond their traditional tasks. The new areas of application of MT will have to be centered around various human-to-human communication media taking into account the different cultures inherent in natura...

Satellites have been very successful for digital broadcast, and it is a natural step to develop IP multicast over satellite to explore the potential of the satellite systems. This paper discusses the issues of IP multicast over satellite, based on IP multicast protocols using different satellite communications systems including DVB-S and DVB-RCS. The paper provides an overview of the networking...

The ITU Radiocommunication Assembly, considering a) that one of the principal limitations in achieving greater utilization of the RF spectrum and geostationary orbit for the fixed-satellite service (FSS) is mutual interference among satellite networks operating in common frequency bands and serving the same or adjacent geographical areas; b) that inter-satellite network interference protection ...

The Space Tethered Autonomous Robotic Satellite (STARS) is being developed in Kagawa University and it will be launched by the H-IIA rocket by Japan Aerospace Exploration Agency (JAXA) in summer 2007. The main purpose of the STARS is technical verification for a tethered space robot proposed in 1995. The STARS consists of mother and daughter satellites connected by tether. The mother satellite ...

The aerospace environment imposes straight operative conditions so every electronic system usually needs to be validated for these. The same way, communication systems need to be evaluated before their introduction in aerospace applications. In the paper we present a new methodology for the evaluation of communication systems in space applications. The methodology aims, by abstraction, at ident...

Any subsequent action to ensure safety can be made only when the current safety level is shown quantitatively, and safety cannot be attained if there is any discrepancy in safety recognition between the controlling party and the controlled party. That is, the significance of Assessment Technology, which is an important technology for safety management, cannot be overlooked. Furthermore, it is n...

A novel ultra-wideband (UWB) bandpass filter (BPF) with notched band based on microstrip/slotline ring resonators is presented in this paper. The UWB BPF is fabricated with two microstrip ring resonators on the top copper layer and a slotline ring resonator on the bottom ground layer. Thus, an ultra-wide passband can be achieved owing to the coupling effects and microstrip/slotline transitions ...

In this article, design and analysis of an optimal orbit control for a communication satellite is investigated. It is the challenging task and critical importance to control the orbit of a communication satellite especially the one used for worldwide communication. The main objective of this work is to evolve a design based on modelling and simulation of an optimal orbit controller for a satell...