I have written a code that samples and quantizes a cosine function and then finds it's FFT. I have got two questions: 1. Why is the output of the FFT shown as a continuous plot ? 2. The FFT doesn't give the correct frequency of my cosine function. Why ?
N=8 m=16 f=m*fs/(2^N); %Frequency of sinusoid
nCyl=16; %generate sixteen cycles of sinusoid
t=0:1/fs:nCyl*1/f; %time index
x=cos(2*pi*f*t); ff=fft(x,256); l=20*log10(ff) plot((20*log10(abs(ff/256))))
Theoretically this code should produce a graph showing a big peak at 16 but that peak is coming at 17 . Why ?
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