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Digital Filter Design

FIR, IIR, windowing, equiripple, least squares, Butterworth, Chebyshev, elliptic, pulse shaping

Design digital filters using as a starting point a set of specifications (designfilt) or a design algorithm (butter, fir1). Generate FIR differentiators and Hilbert filters.


Filter DesignerDesign filters starting with algorithm selection


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butterButterworth filter design
buttordButterworth filter order and cutoff frequency
cheby1Chebyshev Type I filter design
cheb1ordChebyshev Type I filter order
cheby2Chebyshev Type II filter design
cheb2ordChebyshev Type II filter order
designfiltDesign digital filters
ellipElliptic filter design
ellipordMinimum order for elliptic filters
yulewalkRecursive digital filter design
cfirpmComplex and nonlinear-phase equiripple FIR filter design
designfiltDesign digital filters
fir1Window-based FIR filter design
fir2Frequency sampling-based FIR filter design
firclsConstrained-least-squares FIR multiband filter design
fircls1Constrained-least-squares linear-phase FIR lowpass and highpass filter design
firlsLeast-squares linear-phase FIR filter design
firpmParks-McClellan optimal FIR filter design
firpmordParks-McClellan optimal FIR filter order estimation
gaussdesignGaussian FIR pulse-shaping filter design
intfiltInterpolation FIR filter design
kaiserordKaiser window FIR filter design estimation parameters
maxflatGeneralized digital Butterworth filter design
rcosdesignRaised cosine FIR pulse-shaping filter design
sgolaySavitzky-Golay filter design
digitalFilterDigital filter
doubleCast coefficients of digital filter to double precision
dspfwizCreate Simulink filter block using Realize Model panel
filt2blockGenerate Simulink filter block
infoInformation about digital filter
isdoubleDetermine if digital filter coefficients are double precision
issingleDetermine if digital filter coefficients are single precision
polyscaleScale roots of polynomial
polystabStabilize polynomial
singleCast coefficients of digital filter to single precision

Filter Visualization Tool

FVToolFilter Visualization Tool


IIR Filter Design

Compare classical Butterworth, Chebyshev, and elliptic designs. Explore Bessel, Yule-Walker, and generalized Butterworth filters.

FIR Filter Design

Use windowing, least squares, or the Parks-McClellan algorithm to design lowpass, highpass, multiband, or arbitrary-response filters, differentiators, or Hilbert transformers.

Filter Implementation

Filter signals using the filter function.

Anti-Causal, Zero-Phase Filter Implementation

Eliminate the phase distortion introduced by an IIR filter.

Compensate for the Delay Introduced by an FIR Filter

Use indexing to counteract the time shifts introduced by filtering.

Compensate for the Delay Introduced by an IIR Filter

Remove delays and distortion introduced by filtering, when it is critical to keep phase information intact.

Take Derivatives of a Signal

Use a differentiator filter to differentiate a signal without amplifying the noise.

Filter Builder Design Process

filterBuilder is a graphical interface that speeds up the filter design process.

Generating Guitar Chords Using the Karplus-Strong Algorithm

Generate realistic guitar chords using the Karplus-Strong algorithm and discrete-time filters.

Related Information

Featured Examples