On Traffic-demand Based Multi-Beam BandwidthAllocation in Future Satellite Networks Using Beam-Hopping Techniques.

.In this paper we consider adavanced multi-beam satellite communications at the Ka band in GEO satellite systems. In such a scenario an optimum utilization of the limited resources of the network can be achieved by means of beam-hopping techniques, which consist of the selection of a few beams on the overall coverage at each time-slot for transmission, on the basis of the spatial demands for the satellite services. This set of illuminated beams changes on a slot-by-slot basis over the duration of a periodically repeating window. This paper is a preliminary investigation of the implications, trade-offs, and system parameters involved in this new approach, associated with non-uniform bandwidth allocation to the satellite beams. Our target is to match as closely as possible the offered capacity to the traffic demand throughout the satellite coverage region. Since a combined optimization will result in an NP-complete problem, we fix some parameters (e.g. the maximum number of simultaneously illuminated beams in a time-slot) and investigate beam-hopping techniques which consist of a heuristic iterative process. The performance is assessed by means of simulations. We show that beam-hopping techniques, coupled with non-uniform bandwidth and power allocation, are good candidate to enhance mthe performance of the system in terms of bandwidth efficiency and utilization of the limited system resources.