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Approximating ideal filters by systems of fractional order. (English) Zbl 1233.92048
Summary: The contributions in this paper are two fold. On the one hand, we propose a general approach for approximating ideal filters based on fractional calculus from the point of view of systems of fractional order. On the other hand, we suggest that the Paley and Wiener criterion might not be a necessary condition for designing physically realizable ideal filters. As an application of the present approach, we show a case in designing ideal filters for suppressing 50-Hz interference in electrocardiogram (ECG) signals.
MSC:
92C55Biomedical imaging and signal processing, tomography
94A12Signal theory (characterization, reconstruction, filtering, etc.)