Filter Design Toolbox™

Function Reference

Adaptive Filter Constructors

Least Mean Squares (LMS) Based FIR Adaptive Filters	Filter with LMS techniques
Recursive Least Squares (RLS) Based FIR Adaptive Filters	Filter with RLS techniques
Affine Projection (AP) FIR Adaptive Filters	Filter with affine projection
FIR Adaptive Filters in the Frequency Domain (FD)	Filter in the frequency domain
Lattice Based (L) FIR Adaptive Filters	Filter with lattice filters

Least Mean Squares (LMS) Based FIR Adaptive Filters

adaptfilt.adjlms	FIR adaptive filter that uses adjoint LMS algorithm
adaptfilt.blms	FIR adaptive filter that uses BLMS
adaptfilt.blmsfft	FIR adaptive filter that uses FFT-based BLMS
adaptfilt.dlms	FIR adaptive filter that uses delayed LMS
adaptfilt.filtxlms	FIR adaptive filter that uses filtered-x LMS
adaptfilt.lms	FIR adaptive filter that uses LMS
adaptfilt.nlms	FIR adaptive filter that uses NLMS
adaptfilt.sd	FIR adaptive filter that uses sign-data algorithm
adaptfilt.se	FIR adaptive filter that uses sign-error algorithm
adaptfilt.ss	FIR adaptive filter that uses sign-sign algorithm
adaptfilt.swftf	FIR adaptive filter that uses sliding window fast transversal LMS

Recursive Least Squares (RLS) Based FIR Adaptive Filters

adaptfilt.ftf	Fast transversal LMS adaptive filter
adaptfilt.hrls	FIR adaptive filter that uses householder (RLS)
adaptfilt.hswrls	FIR adaptive filter that uses householder sliding window RLS
adaptfilt.qrdrls	FIR adaptive filter that uses QR-decomposition-based RLS
adaptfilt.rls	FIR adaptive filter that uses direct form RLS
adaptfilt.swrls	FIR adaptive filter that uses window recursive least squares (RLS)

Affine Projection (AP) FIR Adaptive Filters

adaptfilt.ap	FIR adaptive filter that uses direct matrix inversion
adaptfilt.apru	FIR adaptive filter that uses recursive matrix updating
adaptfilt.bap	FIR adaptive filter that uses block affine projection

FIR Adaptive Filters in the Frequency Domain (FD)

adaptfilt.fdaf	FIR adaptive filter that uses frequency-domain with bin step size normalization
adaptfilt.pbfdaf	FIR adaptive filter that uses PBFDAF with bin step size normalization
adaptfilt.pbufdaf	FIR adaptive filter that uses PBUFDAF with bin step size normalization
adaptfilt.tdafdct	Adaptive filter that uses discrete cosine transform
adaptfilt.tdafdft	Adaptive filter that uses discrete Fourier transform
adaptfilt.ufdaf	FIR adaptive filter that uses unconstrained frequency-domain with quantized step size normalization

Lattice Based (L) FIR Adaptive Filters

adaptfilt.gal	FIR adaptive filter that uses gradient lattice
adaptfilt.lsl	Adaptive filter that uses LSL
adaptfilt.qrdlsl	Adaptive filter that uses QR-decomposition-based LSL

Discrete-Time Filter Constructors

dfilt.allpass	Allpass filter
dfilt.calattice	Coupled-allpass, lattice filter
dfilt.calatticepc	Coupled-allpass, power-complementary lattice filter
dfilt.cascade	Cascade of discrete-time filters
dfilt.cascadeallpass	Cascade of allpass discrete-time filters
dfilt.cascadewdfallpass	Cascade allpass WDF filters to construct allpass WDF
dfilt.df1	Discrete-time, direct-form I filter
dfilt.df1sos	Discrete-time, SOS direct-form I filter
dfilt.df1t	Discrete-time, direct-form I transposed filter
dfilt.df1tsos	Discrete-time, SOS direct-form I transposed filter
dfilt.df2	Discrete-time, direct-form II filter
dfilt.df2sos	Discrete-time, SOS, direct-form II filter
dfilt.df2t	Discrete-time, direct-form II transposed filter
dfilt.df2tsos	Discrete-time, SOS direct-form II transposed filter
dfilt.dfasymfir	Discrete-time, direct-form antisymmetric FIR filter
dfilt.dffir	Discrete-time, direct-form FIR filter
dfilt.dffirt	Discrete-time, direct-form FIR transposed filter
dfilt.dfsymfir	Discrete-time, direct-form symmetric FIR filter
dfilt.farrowfd	Fractional Delay Farrow filter
dfilt.farrowlinearfd	Farrow Linear Fractional Delay filter
dfilt.latticeallpass	Discrete-time, lattice allpass filter
dfilt.latticear	Discrete-time, lattice, autoregressive filter
dfilt.latticearma	Discrete-time, lattice, autoregressive, moving-average filter
dfilt.latticemamax	Discrete-time, lattice, moving-average filter with maximum phase
dfilt.latticemamin	Discrete-time, lattice, moving-average filter with minimum phase
dfilt.parallel	Discrete-time, parallel structure filter
dfilt.scalar	Discrete-time, scalar filter
dfilt.wdfallpass	Wave digital allpass filter

Filter Specification Objects (fdesign) — Response Types

fdesign.arbmag	Arbitrary response magnitude filter specification object
fdesign.arbmagnphase	Arbitrary response magnitude and phase filter specification object
fdesign.bandpass	Bandpass filter specification object
fdesign.bandstop	Bandstop filter specification object
fdesign.ciccomp	CIC compensator filter specification object
fdesign.decimator	Decimator filter specification object
fdesign.differentiator	Differentiator filter specification object
fdesign.halfband	Halfband filter specification object
fdesign.highpass	Highpass filter specification object
fdesign.hilbert	Hilbert filter specification object
fdesign.interpolator	Interpolator filter specification
fdesign.isinclp	Inverse-sinc filter specification
fdesign.lowpass	Lowpass filter specification
fdesign.notch	Notch filter specification
fdesign.nyquist	Nyquist filter specification
fdesign.octave	Octave filter specification
fdesign.peak	Peak filter specification
fdesign.rsrc	Rational-factor sample-rate converter specification

Filter Specification Objects (fdesign) — Design Methods

cheby1	Chebyshev Type I filter using specification object
cheby2	Chebyshev Type II filter using specification object
designmethods	Methods available for designing filter from specification object
ellip	Elliptic filter using specification object
equiripple	Equiripple single-rate or multirate FIR filter from specification object
fdesign.polysrc	Construct polynomial sample-rate converter (POLYSRC) filter designer
ifir	Interpolated FIR filter from filter specification
kaiserwin	Kaiser window filter from specification object
multistage	Multistage filter from specification object
window	FIR filter using windowed impulse response

Multirate Filter Constructors

mfilt.cascade	Cascade filter objects
mfilt.cicdecim	Fixed-point CIC decimator
mfilt.cicinterp	Fixed-point CIC interpolator
mfilt.farrowsrc	Sample rate converter with arbitrary conversion factor
mfilt.fftfirinterp	Overlap-add FIR polyphase interpolator
mfilt.firdecim	Direct-form FIR polyphase decimator
mfilt.firfracdecim	Direct-form FIR polyphase fractional decimator
mfilt.firfracinterp	Direct-form FIR polyphase fractional interpolator
mfilt.firinterp	FIR filter-based interpolator
mfilt.firsrc	Direct-form FIR polyphase sample rate converter
mfilt.firtdecim	Direct-form transposed FIR filter
mfilt.holdinterp	FIR hold interpolator
mfilt.iirdecim	IIR decimator
mfilt.iirinterp	IIR interpolator
mfilt.iirwdfdecim	IIR wave digital filter decimator
mfilt.iirwdfinterp	IIR wave digital filter interpolator
mfilt.linearinterp	Linear interpolator

GUI-Based Filter Design Methods

fdatool	Open Filter Design and Analysis Tool
filterbuilder	GUI-based filter design

Filter Analysis Methods

autoscale	Automatic dynamic range scaling
block	Generate block from multirate filter
coeffs	Coefficients for filters
cost	Cost of using discrete-time or multirate filter
cumsec	Vector of SOS filters for cumulative sections
denormalize	Undo filter coefficient and gain changes caused by `normalize`
designmethods	Methods available for designing filter from specification object
designopts	Valid input arguments and values for specification object and method
disp	Filter properties and values
double	Cast fixed-point filter to use double-precision arithmetic
euclidfactors	Euclid factors for multirate filter
fftcoeffs	Frequency-domain coefficients
filter	Filter data with filter object
filtstates.cic	Store CIC filter states
firtype	Type of linear phase FIR filter
freqrespest	Estimate fixed-point filter frequency response through filtering
freqrespopts	`freqrespest` parameters and values
freqsamp	Real or complex frequency-sampled FIR filter from specification object
freqz	Frequency response of filter
grpdelay	Filter group delay
help	Help for design method with filter specification
impz	Filter impulse response
isfir	Determine whether filter is FIR
islinphase	Determine whether filter is linear phase
ismaxphase	Determine whether filter is maximum phase
isminphase	Determine whether filter is minimum phase
isreal	Determine whether filter uses real coefficients
isstable	Determine whether filter is stable
limitcycle	Response of single-rate, fixed-point IIR filter
maxstep	Maximum step size for adaptive filter convergence
measure	Measure filter magnitude response
msepred	Predicted mean-squared error for adaptive filter
msesim	Measured mean-squared error for adaptive filter
noisepsd	Power spectral density of filter output
noisepsdopts	Options for running filter output noise PSD
norm	P-norm of filter
normalize	Normalize filter numerator or feed-forward coefficients
normalizefreq	Switch filter specification between normalized frequency and absolute frequency
nstates	Number of filter states
order	Order of fixed-point filter
phasedelay	Phase delay of filter
phasez	Unwrapped phase response for filter
polyphase	Polyphase decomposition of multirate filter
qreport	Most recent fixed-point filtering operation report
realizemdl	Simulink^® subsystem block for filter
reffilter	Reference filter for fixed-point or single-precision filter
reorder	Rearrange sections in SOS filter
reset	Reset filter properties to initial conditions
scale	Scale sections of SOS filter
scalecheck	Check scaling of SOS filter
set2int	Configure filter for integer filtering
setspecs	Specifications for filter specification object
specifyall	Fixed-point scaling modes in direct-form FIR filter
stepz	Step response for filter
validstructures	Structures for specification object with design method
zerophase	Zero-phase response for filter
zplane	Zero-pole plot for filter

To see the full listing of analysis methods that apply to the adaptfilt, dfilt, or mfilt objects, enter help adaptfilt, help dfilt, or help mfilt at the MATLAB^® prompt.

Fixed-Point Filter Construction and Properties

`cell2sos`	Convert cell array to SOS matrix
`get`	Properties of quantized filter
`isreal`	Test if filter coefficients are real
`reset`	Reset properties of quantized filter to initial values
`scale`	Scale sections of SOS filters
`scalecheck`	Check scaling of SOS filter
`scaleopts`	Scaling options for second-order section scaling
`set`	Properties of quantized filter
`sos`	Convert quantized filter to SOS form, order, and scale
`sos2cell`	Convert SOS matrix to cell array

Quantized Filter Analysis Functions

freqz	Frequency response of filter
impz	Filter impulse response
isallpass	Determine whether filter is allpass
isfir	Determine whether filter is FIR
islinphase	Determine whether filter is linear phase
ismaxphase	Determine whether filter is maximum phase
isminphase	Determine whether filter is minimum phase
isreal	Determine whether filter uses real coefficients
issos	Determine whether filter is SOS form
isstable	Determine whether filter is stable
noisepsd	Power spectral density of filter output
noisepsdopts	Options for running filter output noise PSD
zplane	Zero-pole plot for filter

SOS Conversion Functions

`cell2sos`	Convert a cell array to a second-order sections matrix
`sos`	Convert a quantized filter to second-order sections form, order, and scale
`sos2cell`	Convert a second-order sections matrix to a cell array

Filter Design Functions

farrow	Farrow filter
fdatool	Open Filter Design and Analysis Tool
filterbuilder	GUI-based filter design
fircband	Constrained-band equiripple FIR filter
firceqrip	Constrained, equiripple FIR filter
fireqint	Equiripple FIR interpolators
firgr	Parks-McClellan FIR filter
firhalfband	Halfband FIR filter
firlpnorm	Least P-norm optimal FIR filter
firminphase	Minimum-phase FIR spectral factor
firnyquist	Lowpass Nyquist (Lth-band) FIR filter
ifir	Interpolated FIR filter from filter specification
iircomb	IIR comb notch or peak filter
iirgrpdelay	Optimal IIR filter with prescribed group-delay
iirlpnorm	Least P-norm optimal IIR filter
iirlpnormc	Constrained least Pth-norm optimal IIR filter
iirnotch	Second-order IIR notch filter
iirpeak	Second-order IIR peak or resonator filter

Filter Conversion Functions

ca2tf	Convert coupled allpass filter to transfer function form
cl2tf	Convert coupled allpass lattice to transfer function form
convert	Convert filter structure of discrete-time or multirate filter
firlp2hp	Convert FIR lowpass filter to Type I FIR highpass filter
firlp2lp	Convert FIR Type I lowpass to FIR Type 1 lowpass with inverse bandwidth
iirlp2bp	Transform IIR lowpass filter to IIR bandpass filter
iirlp2bs	Transform IIR lowpass filter to IIR bandstop filter
iirlp2hp	Transform lowpass IIR filter to highpass filter
iirlp2lp	Transform lowpass IIR filter to different lowpass filter
iirpowcomp	Power complementary IIR filter
set2int	Configure filter for integer filtering
tf2ca	Transfer function to coupled allpass
tf2cl	Transfer function to coupled allpass lattice

Functions — Alphabetical List