31t.m

来自「包含50个数字信号处理方面的matlab程序」· M 代码 · 共 19 行

Rp=1;Rs=50;ws1=0.4*pi;ws2=0.48*pi;fs=1000;
ws3=(2*fs)*tan(ws1/2);ws4=(2*fs)*tan(ws2/2);
n=10;
[z,p,k]=ellipap(n,Rp,Rs);[b,a]=zp2tf(z,p,k);
w0=sqrt(ws3*ws4);bw=ws4-ws3;
[b1,a1]=lp2bs(b,a,w0,bw);
[bz,az]=bilinear(b1,a1,fs);
[db,mag,pha,grd,w]=freqz_m(bz,az);
subplot(3,1,1);
plot(w/pi,db);
axis([0,1,-100,2]);
n=0:200;
x=sin(0.44*pi*n);
subplot(3,1,2);
plot(n,x);hold on
subplot(3,1,3);
y=filter(bz,az,x);
plot(n,y);