Sinyali Süzme

Fc=100;
Fs=1000;
Fo=25;
Fo2=5;
Fc1=300;
Wn=2*Fc/Fs;
Wn2=2*Fc1/Fs;
t=0:1/Fs:0.5;
ff=linspace(-Fs/2,Fs/2,1024);
%filtre katsayıları oluŞturduk low pass
[b,a]=butter(Fo2,Wn,'low');%5
[c,d]=butter(Fo,Wn,'low');%25
% high pass filtre katsayıları
[e,f]=butter(Fo2,Wn2,'high');%5
[m,n]=butter(Fo,Wn2,'high');%25
%low pass coefficient;
[h1,w1]=freqz(b,a);
[h2,w2]=freqz(c,d);   
h1=freqz(b,a,w1);
h2=freqz(c,d,w2);
%high pass coefficients;
[h3,w3]=freqz(e,f);
[h4,w4]=freqz(m,n);
h3=freqz(e,f,w3);
h4=freqz(m,n,w4);
%%%%


plot(abs(h1));
hold on;
plot(abs(h2));
hold on;
figure(2)
plot(abs(h3));
hold on;
plot(abs(h4));

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x=cos(2*pi*50*t)+sin(2*pi*75*t)+cos(2*pi*120*t)+sin(2*pi*385*t);
y1=filter(c,d,x);
y2=filter(m,n,x);
xf=fftshift(fft(x,1024))/1024;
subplot(3,1,1)
y1f=fft(y1,1024);
plot(ff,abs(fftshift(y1f)/1024));
xlabel('Y1');
subplot(3,1,2);
y2f=fft(y2,1024);
plot(ff,abs(fftshift(y2f))/1024);
xlabel('Y2');
subplot(3,1,3);
plot(ff,abs(xf));
xlabel('XF');