{"title":"Códigos Universais Adaptativos para Representação de Números Inteiros","authors":"Márcio Lima, V. D. Rocha Jr., B. T. Ávila","doi":"10.14209/sbrt.2008.42428","DOIUrl":"https://doi.org/10.14209/sbrt.2008.42428","url":null,"abstract":"— For a given arbitrary list of integer numbers, in general there is no known single universal code which is an overall optimum in the sense of representing the whole list with the shortest average codeword length. This is the main motivation in this paper to introduce adaptive universal codes based on pattern codes. The construction of a class of adaptive universal codes based on Fibonacci codes is given for integer representation which perform well over a wider range of integer values in comparison to known universal code constructions.","PeriodicalId":340055,"journal":{"name":"Anais do XXVI Simpósio Brasileiro de Telecomunicações","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125829800","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Grafos conexos e controle em códigos de treliça","authors":"J. Arpasi, E. Carvalho, L. Tibola","doi":"10.14209/sbrt.2008.42127","DOIUrl":"https://doi.org/10.14209/sbrt.2008.42127","url":null,"abstract":"—The trellis of a binary convolutional code is a connected graph, that is, all the states are connected by some path that is compounded by the concatenation of transitions labeled by encoded bits. When the convolucional code is not binary, then its trellis can be a disconnected graph. In this work it is shown the equivalence between connectedness of graphs and controllability of group codes which are generated from extensions of groups. More precisely; given a group G as an extension U by S , i","PeriodicalId":340055,"journal":{"name":"Anais do XXVI Simpósio Brasileiro de Telecomunicações","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126245004","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Banco de Filtros e Wavelets Cíclicos sobre Corpos de Característica Dois","authors":"G. D. Silva Jr., R. Souza","doi":"10.14209/sbrt.2008.42738","DOIUrl":"https://doi.org/10.14209/sbrt.2008.42738","url":null,"abstract":"","PeriodicalId":340055,"journal":{"name":"Anais do XXVI Simpósio Brasileiro de Telecomunicações","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127538944","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Implementação dos Principais Algoritmos de um Sistema OFDM em Plataforma de Desenvolvimento DSP-FPGA","authors":"Marcos O. Prates, M. Ribeiro","doi":"10.14209/sbrt.2008.42554","DOIUrl":"https://doi.org/10.14209/sbrt.2008.42554","url":null,"abstract":"—This paper aims at to discuss the implementation of the main algorithm of an OFDM system in an Altera‘s DSP-FPGA development platform. First, a brief review about OFDM system is provided, giving an special attention on its basic principles. A introduction on the development board used by the authors is made after that. After that, the implemented OFDM system is detailed. Some results and discussions highlight the potential of DSP-FPGA development platform for multicarrier system implementation.","PeriodicalId":340055,"journal":{"name":"Anais do XXVI Simpósio Brasileiro de Telecomunicações","volume":"324 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133139330","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Pellenz, A. Oliveira, R. D. Souza, Manoel Camillo de Oliveira Penna Neto
{"title":"Avaliação de Desempenho do TCP em Sistemas VBLAST Codificados","authors":"M. Pellenz, A. Oliveira, R. D. Souza, Manoel Camillo de Oliveira Penna Neto","doi":"10.14209/sbrt.2008.42487","DOIUrl":"https://doi.org/10.14209/sbrt.2008.42487","url":null,"abstract":"—The next generation of wireless communications systems will likely incorporate MIMO techniques in order to provide higher data rate multimedia services. Moreover, the transmission control protocol (TCP) is generally employed at the transport layer for reliable data communication. Thus, the optimization of TCP performance over MIMO systems is currently an important research area. In this paper","PeriodicalId":340055,"journal":{"name":"Anais do XXVI Simpósio Brasileiro de Telecomunicações","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133997134","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Estudo de estimadores de Impulsividade em Amostras de Sinais de Comunicações","authors":"E. Ferraz, R. Coelho","doi":"10.14209/sbrt.2008.42897","DOIUrl":"https://doi.org/10.14209/sbrt.2008.42897","url":null,"abstract":"Resumo— Nota-se cada vez mais a presenca de fenomenos impulsivos ou de cauda-pesada em diferentes areas, o que sugere que estes nao possam ser mais modelados como se fossem Gaussianos. Ao mesmo tempo, a modelagem destes processos como nao-Gaussianos motiva a necessidade de uma melhor caracterizacao dos parâmetros que os definem. Neste trabalh o, foram estudados e avaliados os metodos de McCulloch e o QQ plot que estimam impulsividade e indice de cauda. Alem disso, foi proposto um metodo que transpoe as restricoes dos dois primeiros. Os estimadores foram aplicados em sequencias amostrais obtidas de comunicacoes moveis e tambem de geracao de amostras com distribuicoes Pareto e �-estaveis. Palavras-Chave— Processos de cauda-pesada, processos �estaveis, impulsividade, metodo de McCulloch, QQ plot.","PeriodicalId":340055,"journal":{"name":"Anais do XXVI Simpósio Brasileiro de Telecomunicações","volume":"213 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122432043","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Rádio Cognitivo como um Meio de Aumentar a Capacidade de Redes em Malha sem Fio","authors":"R. C. Pereira, R. D. Souza, M. Pellenz","doi":"10.14209/sbrt.2008.42362","DOIUrl":"https://doi.org/10.14209/sbrt.2008.42362","url":null,"abstract":"","PeriodicalId":340055,"journal":{"name":"Anais do XXVI Simpósio Brasileiro de Telecomunicações","volume":"74 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128821506","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
W. Queiroz, Francisco Madeiro Bernardino Junior, M. Alencar
{"title":"Probabilidade de Erro de Bit em Receptor MRC com Modulação QAM sob Desvanecimento Generalizado: Parte II","authors":"W. Queiroz, Francisco Madeiro Bernardino Junior, M. Alencar","doi":"10.14209/sbrt.2008.42825","DOIUrl":"https://doi.org/10.14209/sbrt.2008.42825","url":null,"abstract":"","PeriodicalId":340055,"journal":{"name":"Anais do XXVI Simpósio Brasileiro de Telecomunicações","volume":"59 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128757826","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Projeto e Otimização de Redes TCP/IP com o Dimensionamento de Enlaces e Buffers com Garantia de Qualidade de Serviço","authors":"C. R. C. Bento, E. Wille","doi":"10.14209/sbrt.2008.42783","DOIUrl":"https://doi.org/10.14209/sbrt.2008.42783","url":null,"abstract":"","PeriodicalId":340055,"journal":{"name":"Anais do XXVI Simpósio Brasileiro de Telecomunicações","volume":"68 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114591897","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Uma Arquitetura em Dois Niveis para o Suporte de Comunicação de Tempo-Real em Redes CSMA","authors":"R. Moraes, F. Vasques, Paulo Portugal","doi":"10.14209/sbrt.2008.42527","DOIUrl":"https://doi.org/10.14209/sbrt.2008.42527","url":null,"abstract":"In this paper, a new approach to support real-time (RT) communication in IEEE 802.11 networks is proposed. It is based on a 2-tier architecture. In the lower layer (MAC layer), a forcing collision resolution mechanism enforces a higher priority level to the RT stations. In the upper layer, a coordination mechanism ensures a collision-free access among the set of RT stations. The proposed architecture prioritizes the RT traffic over non-RT traffic, without the need to strictly control the timing behavior of every communication device.","PeriodicalId":340055,"journal":{"name":"Anais do XXVI Simpósio Brasileiro de Telecomunicações","volume":"68 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116237197","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}