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Unformatted text preview: re (3.1)
we have the original time series and the associated DFT (the real and imaginary part).
In Figure (3.2) the original time series after zero padding ( zeros) is used to compute
the DFT. '
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)(&%" ¤¦¨¨¦¤¢ 41 The FFT is not a new transform; the FFT is just a fast algorithm to compute DFTs. The
FFT is based on the halving trick, that is a trick to compute the DFT of length N time
series using the DFT of two subseries of length N/2. Let’s start assuming that we a have
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This note was uploaded on 11/29/2012 for the course GEOPHYSICS 426 taught by Professor Sacchi during the Winter '12 term at University of Alberta.
 Winter '12
 Sacchi

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