Abstract
Future internet demands are constantly increasing, and terrestrial systems are unable to satisfy economically these demands in all geographical areas and thus broadband by satellite is a key potential service provision platform. Key technologies for a future broadband satellite system to provide services to the "unserved" and "underserved" areas are the generation of even smaller beams, with high accuracy and enhanced ACM for Ka band - Q/V band and flexible payloads to cope with the non-homogeneity of the traffic. The research problem involves the studying and modelling of a future broadband satellite system capable of meeting the users’ demands. Firstly, we evaluate and compare the performance of different configurations and how they affect the performance of the system in terms of capacity and QoS. In addition to this, the implications on the payload will be investigated. Secondly, diversity schemes, to cope with the high precipitation fades at the feeder links, are studied. A conceptual overview takes place, and different aspects are examined and evaluated with respect to their effect on the payload. It is concluded that the design of such a system needs to consider both ground and space segment in order to result in an optimised design in terms of cost/bit. Thirdly, flexible options for a high throughput satellite system are investigated and evaluated. For the feeder link, a switching type transparent payload is also considered for the first time and a novel framework is introduced which aims to reduce the capacity losses by tuning the interconnections between feeder links and user links. For the user side and adopting the switching type payload architecture, a method to enhance the system’s flexibility and to better match the users traffic demands by combing flexible bandwidth allocation (Beam Hopping) with irregular beams sizes across the coverage area is proposed. Finally, the results of this study are sum up, and future research topics are proposed.