EquirippleFilterKernel
EquirippleFilterKernel[{{{ωL1,ωR1},{ωL2,ωR2},…},{a1,a2,…}},n]
creates a finite impulse response (FIR) filter kernel of length n with an equiripple amplitude response, given the specified left and right band edge frequencies {ωLi,ωRi} and amplitudes ai.
EquirippleFilterKernel[{{{ωL1,ωR1},{ωL2,ωR2},…},{a1,a2,…},{w1,…}},n]
uses relative weights wi for each frequency band.
EquirippleFilterKernel[{"type",{{{ωL1,ωR1},…},…}},n]
creates a filter of the specified "type".
Details and Options
- EquirippleFilterKernel returns a numeric list of length n of the impulse response coefficients of an FIR filter that has the minimum Chebyshev (minimax) error.
- Possible filter specification types are:
-
"Multiband" multiple passband and stopband filter specification (default) "Differentiator" differentiator filter "Hilbert" Hilbert filter - Frequencies should be given in an ascending order such that 0≤ωL1<ωR1<ωL2<ωR2<…<ωRk≤π.
- The lengths of the lists of frequency bands, amplitudes, and weights should be the same.
- Amplitude values should be non-negative. Typically, values ai=0 specify a stopband, and values ai=1 specify a passband.
- The kernel ker returned by EquirippleFilterKernel can be used in ListConvolve[ker,data] to apply the filter to data.
- The following options can be given:
-
"GridDensity" 8 frequency domain sampling density factor WorkingPrecision MachinePrecision precision to use in internal computations
Examples
open allclose allBasic Examples (1)
Scope (6)
An equiripple highpass FIR filter:
Bode plot of the frequency response of the filter:
Create an equiripple bandpass kernel:
Specify different band weights:
Create an even-length, full-band differentiator:
Phase plot of a Hilbert transformer:
Create an equiripple half-band lowpass filter:
Magnitude plot of the filter and the half-band frequency :
Options (1)
Applications (4)
Properties & Relations (2)
Text
Wolfram Research (2012), EquirippleFilterKernel, Wolfram Language function, https://reference.wolfram.com/language/ref/EquirippleFilterKernel.html.
CMS
Wolfram Language. 2012. "EquirippleFilterKernel." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/EquirippleFilterKernel.html.
APA
Wolfram Language. (2012). EquirippleFilterKernel. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/EquirippleFilterKernel.html