banh
Advanced Member level 1
For an N-point computation of FFT, we have the frequency resolution as (1/N)*fs where fs is the sampling frequency.
Say we have a discrete signal (of length N) with a signal frequency component f0, and X[k] would have one of its peaks at index k0 (i.e. k0 corresponds to f0). In this case, k0 = (f0/fs)*N;
Now, still the same data sequence but appended 0 up to length M (M>N).
We perform M-point FFT on the new padded sequence. Where is the new index of the new peak ?
Say we have a discrete signal (of length N) with a signal frequency component f0, and X[k] would have one of its peaks at index k0 (i.e. k0 corresponds to f0). In this case, k0 = (f0/fs)*N;
Now, still the same data sequence but appended 0 up to length M (M>N).
We perform M-point FFT on the new padded sequence. Where is the new index of the new peak ?