An?lise de desempenho de redes de r?dios cognitivos com sensoriamento espectral perfeito e imperfeito

• Autor(a) principal: Pereira, Gabriel Bearare
• Data de Publicação: 2019
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da INATEL
• Texto Completo: http://tede.inatel.br:8080/tede/handle/tede/181
• topic: Cadeia de Markov; r?dio cognitivo; sensoriamento imperfeito; an?lise de desempenho; Markov chain; cognitive radios; imperfect sensing; performance analysis; Engenharia - Telecomunica??es

The demand for even higher transmission rates coupled with the current scarcity of licensed spectrum in wireless networks underscores the need to optimize spectrum usage in order to support the growing number of connected devices in the networks. The Cognitive Radio networks, object of study in this dissertation, have been studied with the objective of obtaining a better occupation of the spectrum, allowing higher transmission rates to be achieved and to guarantee higher Quality of Service (QoS). Analyzing the performance of Cognitive Radio networks is of paramount importance to ensure the feasibility of implementing such technology. This work analyzes the performance of Cognitive Radio networks for several scenarios, using the concept of queues with priority in the analysis of a Cognitive Radios network where spectral sensing errors are not considered and a continuous- time Markov chain proposed to model the dynamics of a Cognitive Radios network where possible spectral sensing errors occur. Three performance parameters were considered in the analyzes, presenting numerical results, as well as discussions about the results obtained, throughout the dissertation. In addition, the performance parameters are compared between systems where spectral sensing is perfect and imperfect, as well as for some of the possible variations in the parameters of each system.