Physical agents, such as robots, are generally constrained in their communication capabilities. In a multi-agent system composed of physical agents, these constraints have a strong influence on the organization and the coordination mechanisms. Our multi-agent system is a satellite constellation for which we propose a collaboration method based on incremental coalition formation in order to opti...

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...

In this paper the design of a mobile antenna system consisting of a transmitting and receiving sub-systems for Ku band geo-stationary satellite broadcasting and communication is mentioned. A transmitting sub-system plays the role of sending the signal toward the satellite while the receiving sub-system plays the role of receiving signal from the satellite and tracking the target satellite. The ...

Adaptive modulation is a powerful technique to improve the energy efficiency and increases the data rate over a fading channel. The ground station transmitter and the satellite receiver adapt the modulation scheme and the transmitter power to the state of the channel. In this paper, we study adaptive multi-level quadrature amplitude modulation (M-QAM) schemes for LEO satellite over a Rayleigh f...

This paper provides the network synchronization of an orthogonal CDMA geostationary satellite system for fixed service communications. It includes the synchronization procedures, the system architecture and the performance evaluation. The main objective is to provide network wide synchronization of all uplink orthogonal CDMA transmissions. This is achieved in steps; first by providing coarse sy...

Recent evolutions in the context of aeronautical communications have changed the landscape and the role of the different systems that allow aircrafts to maintain a link with the ground while in flight. The increase in capacity needed to support the growth of worldwide air traffic and the need for increased communication safety are driving a transition from voice-centric procedures aided by slow...

Satellite handover happens frequently in Low Earth Orbit (LEO) satellite network due to satellite’s high mobility. In this paper, we propose a novel call admission control scheme which utilizes both the geographical information and the distance between the new call’s position and the preparing handover user’s position in the previous plot beam to intelligently decide whether to block a new call...