Civil Engineering Reference
In-Depth Information
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Frequency (Hz)
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Figure 1.7
Frequency spectrum of the nonstationary signal with frequencies 25, 5 and
10 Hz.
These frequencies can be easily identified on taking the Fourier transform
of the signal. The corresponding Fourier transform of the signal is shown
in Figure 1.7. Let us also assume another nonstationary signal as shown in
Figure 1.8. On performing Fourier transform of this signal, we can clearly
see in Figure 1.9 the dominant peaks again at frequencies 5, 10 and 25 Hz.
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Time (s)
Figure 1.8
Nonstationary signal with frequencies 10, 25 and 5 Hz.
