The current broadband coverage area requisites and the expected user demand is satisfied by the state of the art satellite industry by using multiple spot beams of high throughput satellites with fixed multi-beam pattern and footprint planning. However, in recent years, new mobile broadband users with dynamic traffic demand are requesting for services in remote geographical locations such as air (aeroplanes) and water (ships). Furthermore, the expected demand varies with time and geographical location of the users. Hence, a practical approach to meet such heterogeneous demand is to plan adaptive beams to the satellites equipped with beamforming capabilities. In this paper, we study the state of the art fixed multi-beam pattern and footprint plan and show its drawbacks to support the non-uniformly distributed user terminals and varying traffic demands. To end this, we propose an adaptive multi-beam pattern and footprint plan where we design spot beams with flexible size and position based on the spatial clustering of the users in order to increase the flexibility of the high throughput satellite system. Numerical simulations demonstrate the high system performance of the proposed methodology.

The growing demand for broadband applications has driven the satellite communication service providers to investigate High Throughput Satellite (HTS) solutions. While precoding has been identified as the most promising technique to boost the satellite spectral efficiency, new advanced solutions focus on re-configurable demand-driven systems, where throughput delivered aligns with the time and geographical variations of the traffic demand. For such goal, conventional user scheduling algorithms fail to meet the uneven user traffic demand. In this paper, we propose a novel unicast scheduling algorithm that takes into account both the channel orthogonality required for precoding along with the particular user demands. We name such technique as Weighted Semi-Orthogonal Scheduling (WSOS) methodology. Supporting numerical results are provided that validate the effectiveness of the proposed scheduling and quantify the benefits over conventional scheduling techniques.

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In recent years, dynamic traffic demand requisites have driven the satellite communication service providers to implement reconfigurable demand-driven features to align the delivered throughput with the temporal and geographical variations of the traffic demand. Also, in current interference-limited High Throughput Satellite (HTS) systems, the resulting inter-beam co-channel interference can be mitigated by carefully performing precoding and user scheduling. Unfortunately, the conventional user scheduling algorithms fail to provide demand satisfaction for dynamic traffic demand requisites. Hence, in this paper, we focus on the user scheduling design for precoded satellite systems where both co-channel interference and user demands are taken into account. In particular, we first classify the sectors in each beam according to the interference they may cause to neighboring beams. Next, we formulate the scheduling problem such as the activation of neighboring beam sectors is avoided while proportionally dwelling on the sectors based on their traffic demands. The supporting numerical results for different demand distribution profiles validate the effectiveness of proposed interference-aware demand-based user scheduling over conventional scheduling techniques.INDEX TERMS Multi-beam high throughput satellite systems, beam pattern, beam footprint, DVB-S2X, precoding.

Traditional multi-beam Geostationary (GEO) satellite communication systems provide broadband coverage using a regular grid of fixed spot-beams with uniform 4-colour frequency (4CR) reuse scheme. However, user distribution is non-uniform on ground and, consequently, the demand distribution varies geographically. One potential solution to address high-demand regions is to enhance the satellite beam gain only in those areas. In this paper, we propose the so-called demand driven beam densification approach, which leverages the recent advances in on-board active antenna technologies to generate a higher number of beams over high demand hot-spot areas. Increasing the number of beams result in higher beam overlapping which needs to be carefully considered within the beam frequency planning. In this context, we propose a combination of beam densification, where the number of beams and beam placement is optimized targeting the demand satisfaction objective, followed by frequency-color coding strategy for efficient spectrum and interference management. Supporting results based on numerical simulations show the benefits of the proposed demand driven beam densification in terms of demand matching performance compared with non-densified schemes and regular densification schemes.