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Filter
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Passband Behavior
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Stopband Behavior
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Roll-off Sharpness
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Phase Response
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Typical Use Case
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Butterworth
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Flat (no ripples)
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Smooth decay
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Moderate
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Nonlinear
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General-purpose filtering with minimal distortion in amplitude.
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Elliptic
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Ripple allowed
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Ripple allowed
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Steepest for given order
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Nonlinear
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When very sharp cutoff is needed despite ripple in both bands.
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Bessel
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Flat
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Gentle decay
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Very gradual
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Nearly linear
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Preserving waveform shape and timing (time-domain analyses).
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Chebyshev Type I
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Ripple allowed
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Flat
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Steeper than Butterworth
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Nonlinear
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Applications needing sharper cutoff with acceptable passband ripple.
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Chebyshev Type II
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Flat
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Ripple allowed
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Steeper than Butterworth
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Nonlinear
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Cases where flat passband is critical, but stopband ripple is acceptable.
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.png)
Figure: FFT Spectrum of B-ICC records after applying different filters
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