Discrete Fourier Transform and Signal Spectrum - Digital Signal Processing: Fundamentals and Applications - page 118

5 x 10 5

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Time index n Frequency (Hz)

4 x 10 5

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FIGURE 4.24
Comparison of a one-sided spectrum without using a window function and a one-sided spectrum using the
Hamming window for seismic data.

10000

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60-Hz interference

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Time index n Frequency (Hz)

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Time index n Frequency (Hz)

FIGURE 4.25
Comparison of a one-sided spectrum without using a window function and a one-sided spectrum using the
Hamming window for electrocardiogram data.