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Digital Filtering

Zero-phase filtering, median filtering, overlap-add filtering, transfer function representation

Lowpass, highpass, bandpass, and bandstop filter multichannel data without having to design filters or compensate for delays. Perform zero-phase filtering to remove delay and phase distortion. Use median or Hampel filtering to remove spikes and outliers. Convert transfer functions to different representations, such as second-order sections or poles and zeros.


Signal AnalyzerVisualize and compare multiple signals and spectra


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bandpassBandpass-filter signals
bandstopBandstop-filter signals
highpassHighpass-filter signals
lowpassLowpass-filter signals
fftfiltFFT-based FIR filtering using overlap-add method
filter1-D digital filter
filter22-D digital filter
filtfiltZero-phase digital filtering
filticInitial conditions for transposed direct-form II filter implementation
hampelOutlier removal using Hampel identifier
latcfiltLattice and lattice-ladder filter implementation
medfilt11-D median filtering
residuezZ-transform partial-fraction expansion
sgolayfiltSavitzky-Golay filtering
sosfiltSecond-order (biquadratic) IIR digital filtering
convConvolution and polynomial multiplication
conv22-D convolution
convmtxConvolution matrix
deconvDeconvolution and polynomial division
cell2sosConvert second-order sections cell array to matrix
eqtflengthEqualize lengths of transfer function numerator and denominator
latc2tfConvert lattice filter coefficients to transfer function form
sos2cellConvert second-order sections matrix to cell array
sos2ssConvert digital filter second-order section parameters to state-space form
sos2tfConvert digital filter second-order section data to transfer function form
sos2zpConvert digital filter second-order section parameters to zero-pole-gain form
ssConvert digital filter to state-space representation
ss2sosConvert digital filter state-space parameters to second-order sections form
ss2tfConvert state-space representation to transfer function
ss2zpConvert state-space filter parameters to zero-pole-gain form
tfConvert digital filter to transfer function
tf2latcConvert transfer function filter coefficients to lattice filter form
tf2sosConvert digital filter transfer function data to second-order sections form
tf2ssConvert transfer function filter parameters to state-space form
tf2zpConvert transfer function filter parameters to zero-pole-gain form
tf2zpkConvert transfer function filter parameters to zero-pole-gain form
zp2sosConvert zero-pole-gain filter parameters to second-order sections form
zp2ssConvert zero-pole-gain filter parameters to state-space form
zp2tfConvert zero-pole-gain filter parameters to transfer function form
zpkConvert digital filter to zero-pole-gain representation
dspfwizCreate Simulink filter block using Realize Model panel
filt2blockGenerate Simulink filter block