48t.m

来自「包含50个数字信号处理方面的matlab程序」· M 代码 · 共 16 行

N=31;alpha=(N-1)/2;k=0:N-1;wk=(2*pi/N)*k;
Hk=[ones(1,5),0.5,zeros(1,20),0.5,ones(1,4)];
angH=-alpha*(2*pi)/N*k;H=Hk.*exp(i*angH);
h=real(ifft(H,N));
[db,mag,pha,grd,w]=freqz_m(h,1);
[Hr,ww,a,L]=Hr_Type1(h);
subplot(221);plot(ww/pi,Hr,wk(1:31)/pi,Hk(1:31),'o');axis([0,1,-0.5,1.5]);
subplot(222);plot(w/pi,db);axis([0,1,-130,10]);
N=32;alpha=(N-1)/2;k=0:N-1;wk=(2*pi/N)*k;
Hk=[ones(1,5),0.58,0.12,zeros(1,19),-0.12,-0.58,-ones(1,4)];
angH=-alpha*(2*pi)/N*k;H=Hk.*exp(i*angH);
h=real(ifft(H,N));
[db,mag,pha,grd,w]=freqz_m(h,1);
[Hr,ww,a,L]=Hr_Type2(h);
subplot(223);plot(ww/pi,Hr,wk(1:32)/pi,Hk(1:32),'o');axis([0,1,-0.5,1.5]);
subplot(224);plot(w/pi,db);axis([0,1,-150,10]);