Offered capacity optimization mechanisms for multi-beam satellite systems

Abstract

In this paper we investigate capacity optimization mechanisms for multi-beam satellite systems built on a realistic payload model. The first proposed mechanism deals with long term traffic variations, for which capacity optimization algorithms are proposed based on per-beam traffic requests. Due to the high asymmetry of the traffic, our algorithms provide time and spatial flexibility illuminating a specific set of beams within a window of several time-slots. Our algorithms maximize the amount of capacity actually offered while providing reduced power consumption. The second proposed mechanism deals with short-term traffic variations, for which we propose Network Coding (NC) based techniques at the link layer. The aim is to increase the offered capacity taking advantage of overlapping beam coverage, usually considered as a source of interference. This technique is meant to be applied not only in classical multibeam systems, but also on top of the per-beam capacity optimization as a method to deal with fast traffic unbalances not evaluated in the first mechanism. Analysis and simulations results show that system capacity can be increased up to 13% in the first case and up to 90% in the second case.

Network coding and its applications to satellite systems

“…In broadband satellite systems where tens of beams can cover large geographical areas, many terminals are indeed within regions where two or more beams overlap. Nonetheless, the network coding gains are bounded by the capacity offered by multibeam satellite systems [16], where the performance gains depend on the unused capacity available from adjacent beams. Nonetheless, if terminals are able to simultaneously receive from different beams, then it is possible to exploit the multipath topologies present in multibeam satellite systems.…”

Frequency Packing for Interference Alignment-Based Cognitive Dual Satellite Systems

“…Due to this phenomenon, adjacent carrier interference is introduced which is described in detail in Section IV. We assume perfect bandpass receive filters for simplicity of analysis 1 . The received signal at the primary receiver i.e., SAT1 can be written as:…”

“…To enhance system capacity, satellite systems have moved from payloads generating a single beam to multi-beam platforms [1]. Multiple beams can be employed instead of a single global beam in order to enhance the capacity through spatial frequency reuse [2].…”

Resource Allocation for Cognitive Satellite Uplink and Fixed-Service Terrestrial Coexistence in Ka-Band

“…In this context, Satellite Communications (SatCom) can play a key role to ensure ubiquitous coverage including remote and rural regions, where terrestrial deployment cannot be guaranteed or its cost is prohibitive. Traditional single-beam satellites operating in C/Ku-band show limitations in supporting the flexible distribution of bandwidth needed for broadband applications [3,4]. Novel multi-beam satellites operating in the Ka-band frequency spectrum have recently gained attention among satellite telecommunication industries because they can significantly enhance the system capacity as a result of higher frequency reuse and multiple narrowly focused beams.…”