Re: FFT magnitude trouble

Yes i apply a Hanning window
X[k] = 0.5 * x[k] - 0.25 * x[k-1] - 0.25 * x[k+1] but with or without
window I have different magnitude.
The length of my FFT or FHT is 2048 I m running my program in Visual C++
before to go to the DSP. My input signal length is 2048 too and my
frequency 60 Hz my Ts = 0.0001.
My FFT normalized in frequency is ok. I m still trying to get it, I
analyze a signal with more harmonics (1-42) and I saw that the magnitude
of my harmonics are closely to 1 but never become the same. The highest
harmonic is 1.05 and the lower is 0.88.

Sorry for my foolishness I get that de dc component needs to be the half
to the others components thanks for this I didn?t know, but why all the
components need to be divided by N (including dc)?
If i divide by N my dates are very small and I can´t see them.


Thanks¡¡¡¡¡¡¡¡¡¡¡

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