20t.m

来自「包含50个数字信号处理方面的matlab程序」· M 代码 · 共 22 行

%可抽象成一低通或带阻滤波器。抽象成低通来设计
%抽样频率取fs=1000Hz；
%验证看指标

fp=100;
fs=130;
Rp=2;
Rs=50;
T=0.001; 
wp=2*pi*fp*T;
ws=2*pi*fs*T; 
wp1=(2/T)*tan(wp/2);
ws1=(2/T)*tan(ws/2); 
[n,wn]=cheb1ord(wp1,ws1,Rp,Rs,'s');
[b,a]=cheby1(n,Rp,wn,'low','s'); 
[bz,az]=bilinear(b,a,1/T);
[db,mag,pha,grd,w]=freqz_m(bz,az);
grid on
plot(w/pi,db);
axis([0,1,-80,5]);