ex8p20.m

关于数字信号处理的一些matlab例程

% 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 Eliptic Prototype Filter Calculation:
[cs,ds]=afd_elip(OmegaP,OmegaS,Rp,As);
% ***Elliptic Filter Order=3
% Bilinear transformation:
[b,a]=bilinear(cs,ds,Fs);
[C,B,A]=dir2cas(b,a)