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Filter Design

Design and analyze FIR and IIR filters

You can design and analyze a variety of digital FIR and IIR filters using DSP System Toolbox™ functions, apps, and blocks. Some of these filters include advanced filters such as Nyquist filters, halfband filters, CIC filters, advanced equiripple filters, and quasi-linear phase IIR filters.

The design techniques compute the filter coefficients based on the filter design specifications. Certain blocks such as Bandpass IIR Filter Design and Bandstop IIR Filter Design have tunable filter specifications, so you can change the filter specifications and redesign the filter while the simulation is running.


Filter BuilderDesign filters starting with frequency and magnitude specifications (filterBuilder)

Live Editor Tasks

Design FilterDesign a digital filter or implement a System object in the Live Editor (Since R2021b)


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filterDesignerOpen Filter Designer app
filterBuilderInteractive filter design
fvtoolVisualize frequency response of DSP filters
designfiltDesign a digital filter or implement a System object
butterButterworth IIR digital filter design
cheby1Chebyshev Type I filter using specification object
cheby2Chebyshev Type II filter using specification object
designApply design method to filter specification object
designmethodsMethods available for designing filter from specification object
designoptionsShow all options available for specified design
designoptsValid input arguments and values for specification object and method
ellipElliptic filter using specification object
equirippleEquiripple single-rate FIR filter from specification object
freqsampReal or complex frequency-sampled FIR filter from specification object
helpHelp for design method with filter specification
setspecsSpecifications for filter specification object
validstructuresStructures for specification object with design method
fdesignFilter design specification object
fdesign.bandpassBandpass filter design specification object
fdesign.bandstopBandstop filter design specification object
fdesign.highpassHighpass filter specification object
fdesign.lowpassLowpass filter specification
fdesign.decimatorDecimator filter specification object
fdesign.interpolatorInterpolator filter specification
fdesign.rsrcRational-factor sample-rate converter specification
fdesign.arbgrpdelayArbitrary group delay filter specification object
fdesign.arbmagArbitrary response magnitude filter specification object
fdesign.arbmagnphaseArbitrary response magnitude and phase filter specification object
fdesign.ciccompCIC compensator filter specification object
fdesign.combIIR comb filter specification object
fdesign.differentiatorDifferentiator filter specification object
fdesign.fracdelayFractional delay filter specification object
fdesign.halfbandHalfband filter specification object
fdesign.hilbertHilbert filter specification object
fdesign.isinchpInverse sinc highpass filter specification
fdesign.isinclpInverse sinc lowpass filter specification
fdesign.notchNotch filter specification
fdesign.nyquistNyquist filter specification
fdesign.peakPeak filter specification
fdesign.polysrcConstruct polynomial sample-rate converter (POLYSRC) filter designer
designLowpassFIRDesign and implement lowpass FIR filter (Since R2023b)
designHighpassFIRDesign and implement highpass FIR filter (Since R2023b)
designBandpassFIRDesign and implement bandpass FIR filter (Since R2023b)
designBandstopFIRDesign and implement bandstop FIR filter (Since R2023b)
designHalfbandFIRDesign and implement halfband FIR filter (Since R2023b)
designMultirateFIRDesign and implement antialiasing and anti-imaging lowpass FIR filter
designMultistageDecimatorMultistage decimator design
designMultistageInterpolatorMultistage interpolator design
designFracDelayFIRDesign and implement band-limited fractional delay FIR filter (Since R2021a)
fircbandConstrained-band equiripple FIR filter
firceqripConstrained equiripple FIR filter
fireqintEquiripple FIR interpolators
firgrParks-McClellan FIR filter
firlpnormLeast P-norm optimal FIR filter
firlsLeast-square linear-phase FIR filter design
firminphaseMinimum-phase FIR spectral factor
firnyquistLowpass Nyquist (Lth-band) FIR filter
firpr2chfbTwo-channel FIR filter bank for perfect reconstruction
ifirInterpolated FIR filter design
normalizefreqSwitch filter specification between normalized frequency and absolute frequency
designLowpassIIRDesign and implement lowpass IIR filter (Since R2023b)
designHighpassIIRDesign and implement highpass IIR filter (Since R2023b)
designBandpassIIRDesign and implement bandpass IIR filter (Since R2023b)
designBandstopIIRDesign and implement bandstop IIR filter (Since R2023b)
designHalfbandIIRDesign and implement halfband IIR filter in the form of a coupled allpass filter (Since R2023b)
designNotchPeakIIRDesign and implement high-order Butterworth notch or peak IIR filter (Since R2023b)
ca2tfConvert coupled allpass filter to transfer function form
cl2tfConvert coupled allpass lattice to transfer function form
iircombIIR comb notch or peak filter
iirgrpdelayOptimal IIR filter with prescribed group-delay
iirlpnormLeast P-norm optimal IIR filter
iirlpnormcConstrained least Pth-norm optimal IIR filter
normalizefreqSwitch filter specification between normalized frequency and absolute frequency


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dsp.DifferentiatorDirect form FIR fullband differentiator filter
dsp.HampelFilterFilter outliers using Hampel identifier
dsp.HighpassFilterFIR or IIR highpass filter
dsp.LowpassFilterFIR or IIR lowpass filter
dsp.MedianFilterMedian filter
dsp.NotchPeakFilterSecond-order tunable notching and peaking IIR filter
dsp.VariableBandwidthFIRFilterVariable bandwidth FIR filter
dsp.VariableBandwidthIIRFilterVariable bandwidth IIR filter
dsp.CICCompensationDecimatorCompensate for CIC decimation filter using FIR decimator
dsp.CICCompensationInterpolatorCompensate for CIC interpolation filter using FIR interpolator
dsp.FIRHalfbandDecimatorHalfband decimator
dsp.FIRHalfbandInterpolatorHalfband interpolator
dsp.IIRHalfbandDecimatorDecimate by factor of two using polyphase IIR
dsp.IIRHalfbandInterpolatorInterpolate by a factor of two using polyphase IIR


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Analog Filter DesignDesign and implement analog filters
Digital Filter DesignDesign and implement digital FIR and IIR filters
Filter Realization WizardConstruct filter realizations using digital filter blocks or Sum, Gain, and Delay blocks
Lowpass FIR Filter DesignDesign lowpass FIR filter with tunable filter specifications (Since R2023b)
Lowpass IIR Filter DesignDesign lowpass IIR filter with tunable filter specifications (Since R2023b)
Highpass FIR Filter DesignDesign highpass FIR filter with tunable filter specifications (Since R2023b)
Highpass IIR Filter DesignDesign highpass IIR filter with tunable filter specifications (Since R2023b)
Bandpass FIR Filter DesignDesign bandpass FIR filter with tunable filter specifications (Since R2023b)
Bandpass IIR Filter DesignDesign bandpass IIR filter with tunable filter specifications (Since R2023a)
Bandstop FIR Filter DesignDesign bandstop FIR filter with tunable filter specifications (Since R2023b)
Bandstop IIR Filter DesignDesign bandstop IIR filter with tunable filter specifications (Since R2023a)
Differentiator FilterDirect form FIR fullband differentiator filter
Hampel FilterFilter outliers using Hampel identifier
Highpass FilterDesign FIR or IIR highpass filter
Lowpass FilterDesign FIR or IIR lowpass filter
Median FilterMedian filter
Notch-Peak FilterDesign second-order tunable notching and peaking IIR filter
Variable Bandwidth FIR FilterDesign tunable bandwidth FIR filter
Variable Bandwidth IIR FilterDesign tunable bandwidth IIR filter