![](v3_space.gif) |
![](v3_space.gif) |
![](v3_space.gif) |
![](v3_space.gif) |
![](v3_space.gif) |
(1)
Direct Method (a more popular method)
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Step 1: Perform Fourier
transform of y(t) to get C2(k)
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Step 2: smooth C2(k) by averaging a few adjacent
frequencies together.
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or by
averaging the spectra of a few time series together.
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è both ways smooth a line spectrum to a continuous
spectrum and
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increase the degrees
of freedom of the spectrum.
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