Digital Signal Processing Reference
In-Depth Information
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Figure 12.20
(a) Hamming window;
(b) Hanning window.
(b)
gradually approach zero at the limits of the sequence rather than cut off abruptly, as
the rectangular window does. This gradual change in the time domain results in a
narrower bandwidth in the frequency domain and, therefore, less spectrum-leakage
distortion in the DFT. The next example demonstrates the effect of spectrum-leakage
distortion and the difference in spectrum-leakage distortion that is made by changing
the shape of the window.
