cheby2
Chebyshev Type II filter using specification object
Syntax
chebTwoFilter= design(d,'cheby2','SystemObject',true)
chebTwoFilter = design(d,'cheby2',designoption,value,designoption,
value,'SystemObject',true)
Description
chebTwoFilter= design(d,'cheby2','SystemObject',true) designs
a Chebyshev II IIR digital filter using the specifications supplied
in the object d.
chebTwoFilter = design(d,'cheby2',designoption,value,designoption, returns a Chebyshev
II IIR filter where you specify design options as input arguments.
value,'SystemObject',true)
To determine the available design options, use designopts with the specification object
and the design method as input arguments as shown.
designopts(d,'method')
For complete help about using cheby2, refer
to the command line help system. For example, to get specific information
about using cheby2 with d, the
specification object, enter the following at the MATLAB prompt.
help(d,'cheby2')
Examples
Design a Chebyshev Type II Filter
Construct a default lowpass filter specification object and design a Chebyshev Type II filter.
d = fdesign.lowpass;
Use matchexactly option to ensure the performance of the filter in the passband.
LowpassCheb2 = design(d,'cheby2','matchexactly','passband',... 'SystemObject',true);
Use fvtool to view the resulting filter
fvtool(LowpassCheb2)
Construct a highpass filter specification object and design a Chebyshev Type II filter. Specify the filter order, stopband edge frequency, and the stopband attenuation to get the filter exactly as required.
d = fdesign.highpass('n,fst,ast',5,20,55,50); HighpassCheb2 = design(d,'cheby2','SystemObject',true);
Use fvtool to view the resulting filter
fvtool(HighpassCheb2)
By design, cheby2 returns filters that use second-order sections (SOS). For many applications, and for most fixed-point applications, SOS filters are particularly well-suited.