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Estudio de técnicas de gestión de recursos para mejorar la eficiencia de sistemas WLAN

Source: OAI

ABSTRACT El presente trabajo de fin de carrera se sitúa en el ámbito de las comunicaciones inalámbricas y concretamente en las redes WLAN basadas en el estándar IEEE 802.11. Los objetivos del trabajo han sido proponer y estudiar técnicas basadas en el diseño Cross-Layer con el fin de mejorar la eficiencia y el aprovechamiento de los recursos disponibles en redes WLAN. La idea fundamental del diseño Cross-Layer consiste en permitir un intercambio de información entre las capas del modelo OSI que forman el sistema de comunicaciones. En el presente trabajo se han propuesto técnicas Cross-Layer que utilizan la información proveniente de la capa física en la capa MAC, adaptando las transmisiones según el estado del canal radio. Haciendo uso de un protocolo MAC de alta eficiencia llamado DQCA (Distributed Queueing Collision Avoidance), se han llevado a cabo simulaciones por ordenador con tal de evaluar y cuantificar las mejoras que las técnicas propuestas ofrecen en distintos escenarios significativos. Además, se ha verificado la consistencia de resultados teóricos previos acerca del protocolo DQCA a través de la comparación con resultados obtenidos mediante simulación por ordenador. El análisis de los resultados obtenidos ha permitido concluir que las técnicas propuestas ofrecen mejoras significativas en los distintos escenarios de trabajo considerados, especialmente en términos de throughput y retardo medio. Sus principales virtudes son la sencillez de implementación y los buenos resultados que ofrecen en cuanto al aprovechamiento de los recursos del sistema. Tras el estudio realizado concluimos que las técnicas propuestas permiten mejorar la eficiencia de sistemas WLAN de forma significativa y por tanto se trata de propuestas interesantes a tener en cuenta en el diseño de futuras redes inalámbricas.

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