firchuanghanshu.m

一个ＤＣＴ函数的程序

passrad=0.2*pi;
w1=boxcar(81);
w2=triang(81);
w3=hanning(81);
w4=hamming(81);
n=1:1:81;
hd=sin(passrad*(n-41))./(pi*(n-41));
hd(41)=passrad/pi;
h1=hd.*rot90(w1);
h2=hd.*rot90(w2);
h3=hd.*rot90(w3);
h4=hd.*rot90(w4);
[MAG1,RAD]=freqz(h1);
[MAG2,RAD]=freqz(h2);
[MAG3,RAD]=freqz(h3);
[MAG4,RAD]=freqz(h4);
subplot(2,2,1);
plot(RAD,20*log10(abs(MAG1)));
grid on;
subplot(2,2,2);
plot(RAD,20*log10(abs(MAG2)));
grid on;
subplot(2,2,3);
plot(RAD,20*log10(abs(MAG3)));
grid on;
subplot(2,2,4);
plot(RAD,20*log10(abs(MAG4)));
grid on;