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One wants to approximate the trigonometric polynomial
in
(2.4) by a linear combination of shifted 1-periodic window
functions
as
![$\displaystyle s_1\left(x\right) := \sum_{l \in I_n} g_{l} \; \tilde \varphi\left(x - \frac{l}{n}\right) \, .$](img81.png) |
(2.5) |
With the help of an oversampling factor
, the FFT length is given by
.
Jens Keiner
2006-11-20