Download Two-Dimensional Fourier Processing of

(a) Rectangular Window
(b) Hamming Window
Figure 4.7: Window Function Time and Frequency Representations
The Matlab Signal Processing toolbox provides a window analysis tool which was used to
observe the frequency response of a rectangular window, as shown in figure 4.7a. Figure
4.7b shows a Hamming window in the time and frequency domains to serve as a comparison.
Both window functions have a frequency domain form that resembles a sinc function, with
a main frequency lobe with many lower magnitude side lobes. The rectangular window
has a narrower main lobe but at the expense of much higher magnitude side lobes. These
side lobes cause the spectral representation of a non-synchronised sinusoidal component to
leak energy into adjacent frequency bands, reducing the clarity of its representation.
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