Precoded Cluster Hopping for Multibeam GEO Satellite Communication Systems

Abstract

Beam hopping (BH) and precoding are two trending technologies for high-throughput satellite (HTS) systems. While BH enables the flexible adaptation of the offered capacity to the heterogeneous demand, precoding aims at boosting the spectral efficiency. In this study, we consider an HTS system that employs BH in conjunction with precoding in an attempt to bring the benefits of both in one. In particular, we propose the concept of cluster hopping (CH), where a set of adjacent beams are simultaneously illuminated with the same frequency resource. On this line, we propose an efficient time–space illumination pattern design, where we determine the set of clusters that shall be illuminated simultaneously at each hopping event along with the dwelling time. The CH time–space illumination pattern design formulation is shown to be theoretically intractable due to the combinatorial nature of the problem and the impact of the actual illumination design on the resulting interference. For this, we make some design decisions on the beam–cluster design that open the door to a less complex still well-performing solution. Supporting results based on numerical simulations are provided which validate the effectiveness of the proposed CH concept and a time–space illumination pattern design with respect to benchmark schemes.

The Next Generation of Beam Hopping Satellite Systems: Dynamic Beam Illumination With Selective Precoding

“…Monte Carlo simulations are conducted to evaluate the performance of the proposed three algorithms in terms of demand matching, the total computation for precoding and average number of active beams per TS, comparing with two benchmarks: conventional beam hopping (BH) and cluster hopping (CH). In particular, the conventional BH method is given in Appendix A while CH benchmark solution is proposed in [29,30].…”

“…2) Cluster Hopping: The activation of an adjacent set of beams (referred as cluster) was investigated within the European Space Agency (ESA) [28] and proposed in [29,30] with the so-called Cluster Hopping (CH) scheme, where linear precoding [14] was considered to mitigate the resulting intracluster interference. The downside of the works in [29,30] is the fact that the overall virtual multi-beam grid is split into a set of non-overlapping clusters of fixed size and shape. This is done to reduce the search space and exclude the cluster design from the optimization problem.…”

“…This is done to reduce the search space and exclude the cluster design from the optimization problem. While some practical guidelines about the clustering design have been discussed in [30], the problem remains largely unsolved, especially when considering the complexity added by the precoding within the clusters.…”

“…Regarding the same approach analyzing the convergence of the MP method given in [33], one can prove the convergence of the proposed algorithm by addressing two facts: i) for given η [ℓ] , ρ [ℓ] , the MM procedure converges to the global optimum of x [ℓ] ; ii) the sequence {η [ℓ] } updated as in (30) converges to a fixed Lagrangian multiplier of P1 . Ãj,n + Ãn,j x bin j,t , ∀(n, t).…”

A Survey on Nongeostationary Satellite Systems: The Communication Perspective

“…1) Resources Management and Optimization: In order to satisfy the growing traffic demand a thorough design of the resource allocation strategies with respect to power, bandwidth, time interval, beam and antenna (to exploit spatial diversity), needs to be done, cf. [202]. Nevertheless, the demand satisfaction is much more challenging with NGSO compared to GSO satellites because of less available resources due to a much smaller payload [203], [204].…”