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Options Region

This region allows you to specify the filter design method options. FIR Equiripple, FIR Window, and some Filter Design Toolbox design methods have settable options.

FIR Equiripple and Complex Equiripple Option

The FIR Equiripple and FIR Complex Equirpple design methods, which uses the firpm and cfirpm functions, respectively, have a Density Factor option. This option controls the density of the frequency grid. Increasing the value creates a filter which more closely approximates an ideal equiripple filter, but the time required for computation increases.

FIR Window Options

The FIR Window design method has four options:

The following windows and settable parameters are available.

Window
Corresponding Function
Parameter
Bartlett
bartlett
none
Bartlett-Hanning
barthannwin
none
Blackman
blackman
none
Blackman-Harris
blackmanharris
none
Bohman
bohmanwin
none
Chebyshev
chebwin
Sidelobe atten.--amount of dB sidelobe is below mainlobe
Flat Top
flattopwin
none
Gaussian
gausswin
Alpha--affects the width of the window. Larger alpha produces a more narrow window.
Hamming
hamming
none
Hann
hann
none
Kaiser
kaiser
Beta--affects sidelobe attenuation. Higher beta widens the mainlobe and decreases the sidelobe amplitude.
Nuttall
nuttallwin
none
Rectangular
rectwin
none
Tukey (cosine-tapered)
tukeywin
Alpha--specifies the ratio of taper to constant sections, affecting the window shape. Alpha is between 0 and 1.
Triangular
triang
none
User defined
user defined function name
user-defined parameter

View Button

The View button launches the Window Visualization Tool (wvtool) where you can view and compare windows.


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