Abstract
Algorithms for moving average, recursive and “Fourier transform” low-pass linear digital filters are described, with reference being made to the methods of design. The characteristics, including frequency, phase and impulse responses, of four specific filters are discussed in detail. In addition, some of the practical problems of programming these filters are considered. Factors such as execution times are evaluated in concluding which designs are most appropriate for filtering electrocardiograms.
Sommaire
Cet article décrit les algorithmes des filtres numériques linéaires pass-bas à moyenne mobile, å répétition et à transformation de ‘Fourier’; l'aubteur se refère aux méthodes de conception de ces filtres. Il examine en détail les caractéristiques telles que la réponse de fréquence, de phase et d'impulsion de quatre filtres spécifiques. En outre, il considère quelques uns des problèmes pratiques que l'on rencontre lors de la programmation de ces filtres. Il évalue des facteurs tels que les temps d'exécution et conclut en sélectionnant les modèles les plus appropriés au fitrage des électrocardiogrammes.
Zusammenfassung
Es werden Algorithmen zum Bewegen durchschnittlicher, rekursiver und linearer Digital-Tiefpaßfilter ‘Fourier Transform’ unter Bezugnahme auf die Konstruktionsverfahren beschrieben. Die Eigenschaften von vier Einzelfiltern wie Frequenz, Phasenabhängigkeit und Impulsverhalten werden genau besprochen. Ferner werden praktische Probleme zur Programmierung dieser Filter berücksichtigt. Faktoren wie Durchführungszeiten werden bewertet. Der Artikel untersucht abschließend, welche Ausführungen sich am besten zum Filtern von Elektrokardiogrammen eignen.
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Taylor, T.P., Macfarlane, P.W. Digital filtering of the e.c.g.—a comparison of low-pass digital filters on a small computer. Med. & biol. Engng. 12, 493–502 (1974). https://doi.org/10.1007/BF02478607
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DOI: https://doi.org/10.1007/BF02478607