Hi Folks,
I need to modify the code so that I am reporting the correct frequencies calculated from the fft
Fs=9827.2*2;t=0:1/Fs:0.06756;f=14.8;f_1=1228.4;x=cos(2*pi*t*f)+cos(2*pi*t*f_1);nfft=664;X=fft(x,nfft);X = X(1:nfft/2); mx=abs(X);f=(0:nfft/2-1)*Fs/nfft/2;figure(1);plot(t,x);title('Cosine wave Signal');ylabel('Amplitude');figure(2); plot(f,mx);title('Power Spectrum of a sine wave');xlabel('Frequency(hz)');ylabel('Power')
I expect to see the 2 fundamental frequencies 14.8Hz and 1228.4Hz (83*14.8) in the frequency window, however, it reports 14.8Hz and 621.9Hz( 14.8*42)instead.
Thanks
Best Answer