[ES] El objetivo de esta tesina es la implementación de un scheduler de paquetes para en enlace descendente en un sistema de comunicaciones por satélite DVB-S2 en las bandas Ka/Ku. Este scheduler aprovechará las ventajas ...[+]
[ES] El objetivo de esta tesina es la implementación de un scheduler de paquetes para en enlace descendente en un sistema de comunicaciones por satélite DVB-S2 en las bandas Ka/Ku. Este scheduler aprovechará las ventajas de la técnica de Adaptive Coding and Modulation para optimizar al máximo la transmisión de los paquetes.
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[EN] The standard DVB-S2 promises an efficiency gain of around 30% in comparison with the first
specification. This is achieved thanks to several advanced techniques such as Forward Error Correction
(FEC), new high-order ...[+]
[EN] The standard DVB-S2 promises an efficiency gain of around 30% in comparison with the first
specification. This is achieved thanks to several advanced techniques such as Forward Error Correction
(FEC), new high-order modulations, a wide range of coding rates, new roll-off factors or the technique
known as Adaptive Coding and Modulation (ACM). ACM allows to optimize individually the physical layer
protection of each frame containing packets of users that match in the payload according to the measured
SNIR in the receivers. Each user reports periodically its channel conditions by means of a return channel.
However, all of these efficiency improvements could be suppressed due to an inadequate management of the
resources. The goal of this thesis is to design a packet scheduler in the gateway for the forward link, hereafter
known as Pool Scheduler. This scheduler will use the information provided by the return channel in order to
manage and optimize the resources while providing certain quality of service (QoS) to the users, which are in
general conflicting goals. The performance of the Pool Scheduler is compared to a Benchmark, which is
based on the architecture approach proposed in the DVB-S2 implementation guidelines. Results in terms of
achieved throughput, system efficiency, delay or jitter conclude that the Pool Scheduler performance is better
than the Benchmark one and can work in a real satellite system
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