Chebyshev Type II filter using specification object
hd = design(d,'cheby2')
hd = design(d,'cheby2',designoption,value,designoption,
To determine the available design options, use designopts with the specification object and the design method as input arguments as shown.
For complete help about using cheby1, 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.
These examples use filter specification objects to construct Chebyshev type I filters. In the first example, you use the matchexactly option to ensure the performance of the filter in the passband.
d = fdesign.lowpass; hd = design(d,'cheby2','matchexactly','passband');
cheby2 also designs highpass, bandpass, and bandstop filters. Here is a highpass filter where you specify the filter order, the stopband edge frequency. and the stopband attenuation to get the filter exactly as required.
d = fdesign.highpass('n,fst,ast',5,20,55,50); hd=design(d,'cheby2');
The Filter Visualization Tool shows the highpass filter meets the specifications.
By design, cheby2 returns filters that use second-order sections. For many applications, and for most fixed-point applications, SOS filters are particularly well-suited for use.