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EquirippleFilter

EquirippleFilter[N, {f₁, f₂, ...}, {v₁, v₂, ...}] returns a 1D linear-phase FIR filter of length N with band edge frequencies given by f₁, f₂, ... and desired magnitude values given by v₁, v₂, ... and that exhibits equiripple behavior in the frequency range of interest.

EquirippleFilter[N, {f₁, f₂, ...}, {v₁, v₂, ...}, {w₁, w₂, ...}] returns a 1D linear-phase FIR filter of length N with band edge frequencies given by f₁, f₂, ..., desired magnitude values given by v₁, v₂, ..., and relative weights in each band given by w₁, w₂, ... and that exhibits equiripple behavior in the frequency range of interest.

EquirippleFilter[N, {f₁, f₂, ...}, {v₁, v₂, ...}, {w₁, w₂, ...}, type] returns a 1D linear-phase FIR filter of length N and type given by type, with band edge frequencies given by f₁, f₂,..., desired magnitude values given by v₁, v₂, ..., and relative weights in each band given by w₁, w₂, ... and that exhibits equiripple behavior in the frequency range of interest.

EquirippleFilter implements an algorithm commonly known as the McClellan, Parks, and Rabiner algorithm [McC73b].

The band edge frequencies must increase monotonically, so that 0≤f₁≤f₂≤...≤ 0.5.

The length of the lists of band edge frequencies and magnitude values must satisfy Length[{f₁,f₂, ...}] = 2Length[{v₁,v₂, ...}].

Filter types may be "bandpass" (default), "differentiator", and "Hilbert".

See also User's Guide 9.3.

Examples

This loads the package.

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This returns a lowpass filter.

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Here we verify the frequency response of the filter.

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Here is the same lowpass filter with improved stopband attenuation.

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Here we verify the frequency response of the filter.

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Here is a differentiator.

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Here we verify the frequency response of the filter.

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