ex8p19.m

来自「关于数字信号处理的一些matlab例程」· M 代码 · 共 16 行

%Digital Filter Specifications:
wp=0.2*pi;              %       digital Passband freq in rad
ws=0.3*pi;              %       digital Stopband freq in rad
Rp=1;                   %       Passband ripple in dB
As=15;                  %       Stopband attenuation in dB
% Analog Prototype Specifications:Inverse mapping for frequencies
T=1;Fs=1/T;               %          Set T=1
OmegaP=(2/T)*tan(wp/2);   %          Prewarp Prototype Passband freq
OmegaS=(2/T)*tan(ws/2);   %          Prewarp Prototype Stopband freq 
% Analog Chebyshev-2 Prototype Filter Calculation:
% ***Chebyshev-2 Filter Order=4
% Bilinear transformation:
[cs,ds]=afd_chb2(OmegaP,OmegaS,Rp,As);
[b,a]=bilinear(cs,ds,Fs);
[C,B,A]=dir2cas(b,a)