Advertisement
Not a member of Pastebin yet?
Sign Up,
it unlocks many cool features!
- fs = 48000;
- [xn,fs] = audioread('eric.wav');
- nf=1024;
- Y = fft(xn,nf);
- f = fs/2*linspace(0,1,nf/2+1);
- plot(f,abs(Y(1:nf/2+1)));
- filteredf = lowpass(Y,4000,fs);
- filteredt = ifft (filteredf);
- sound(filteredf,Fs);
- Fc = 100000;
- Fm = 500000;
- [p,q]=rat(fs/Fm);
- filtere=resample(filteredt,p,q);
- filte = fft(filtere,nf);
- x = cos (2*pi*Fc*t);
- z = filte.*x;
- demod = z.*cos(2*pi*Fc*t);
- [b,a] = butter(5,Fc*2/Fm);
- demod = filtfilt(b,a,demod);
- z1= awgn(z , 0 ,'measured');
- demod1 = z1.*cos(2*pi*Fc*t);
- [b,a] = butter(5,Fc*2/Fm);
- demod1 = filtfilt(b,a,demod1);
- z2= awgn(z , 10 ,'measured');
- demod2 = z2.*cos(2*pi*Fc*t);
- [b,a] = butter(5,Fc*2/Fm);
- demod2 = filtfilt(b,a,demod2);
- z3 = awgn(z ,30 ,'measured')
- demod3 = z3.*cos(2*pi*Fc*t);
- [b,a] = butter(5,Fc*2/Fm);
- demod3 = filtfilt(b,a,demod3);
- z1f = fft(z1,nf);
- z2f = fft(z2,nf);
- z3f = fft(z3,nf);
- plot(z1f);title('SNR =0 in frequency');
- plot(z2f);title('SNR =10 in frequency');
- plot(z3f);title('SNR =30 in frequency');
- plot(z1);title('SNR =0 in time');
- plot(z2);title('SNR =10 in time');
- plot(z3);title('SNR =30 in time');
- [p1,q1]=rat(Fm/fs);
- z1fs=resample(z1f,p1,q1);
- z2fs=resample(z2f,p1,q1);
- z3fs=resample(z3f,p1,q1);
- sound(z1fs,fs);
- sound(z2fs,fs);
- sound(z3fs,fs);
- fc2 = 100100 ;
- z4= awgn(z , 10 ,'measured');
- demod4 = z2.*cos(2*pi*fc2*t);
- [b,a] = butter(5,fc2*2/Fm);
- demod4 = filtfilt(b,a,demod4);
- z5= awgn(z , 10 ,'measured');
- demod5 = z2.*cos(2*pi*fc*t+20);
- [b,a] = butter(5,fc*2/Fm);
- demod5 = filtfilt(b,a,demod5);
Advertisement
Add Comment
Please, Sign In to add comment
Advertisement