49t.m

包含50个数字信号处理方面的matlab程序

N=241;alpha=(N-1)/2;k=0:N-1;wk=(2*pi/N)*k;
f1=50;f2=250;fs=1000;L=40;
Hk=[ones(1,49),zeros(1,144),ones(1,48)];
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(3,1,1);plot(w/pi,db);axis([0,1,-100,10]);title('frequency domain');
n=0:240;t=0.001*n;
x=sin(2*f1*pi*t)+sin(2*f2*pi*t);
subplot(3,1,2);hold on;stem(n,x,'.');axis([80,240,-2,2]);
y=filter2(h,x);
subplot(3,1,3);stem(n,y,'.');axis([80,240,-1.2,1.2]);