I am working on a very simple voice recognition system using the msp430. In my research I've read that for real life audio signals its necessary to apply a window to the FFT data because the audio signals won't be periodic. In my code, I've applied the hamming window and plotted it against the non-windowed FFT spectrum. It appears that the hamming attenuates the signal in the lower valued N data points.
I think this makes sense based upon the equation of the hamming window, but why would I want this attenuate for my signal? It seems that identifying the spectral characteristics would be more difficult after the window. Any thoughts?