SPC-Threshold: Uma Proposta de Limiarização para Filtragem Adaptativa de Sinais

F. M. Bayer, A. J. Kozakevicius

Abstract


Neste trabalho é apresentada uma proposta de limiarização para filtragem adaptativa de sinais por meio do truncamento dos coeficientes wavelets do sinal analisado. O parâmetro de corte para limiarização é estimado por analogia à aplicação dos gráficos de controle, que é uma ferramenta do controle estatístico de processo (SPC - Statistical Process Control ). O método proposto, denominado SPC-Threshold, é formulado e para sua validação são realizadas simulações computacionais. Os resultados do SPC-Threshold são comparados com aqueles obtidos com limiares de truncamento já consagrados, como o Universal Threshold, o SURE Threshold e suas variações.

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DOI: https://doi.org/10.5540/tema.2010.011.02.0121

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Trends in Computational and Applied Mathematics

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