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On a connection between nonstationary and periodic wavelets

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 Added by Elena A. Lebedeva
 Publication date 2016
  fields
and research's language is English




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We compare frameworks of nonstationary nonperiodic wavelets and periodic wavelets. We construct one system from another using periodization. There are infinitely many nonstationary systems corresponding to the same periodic wavelet. Under mild conditions on periodic scaling functions, among these nonstationary wavelet systems, we find a system such that its time-frequency localization is adjusted with an angular-frequency localization of an initial periodic wavelet system. Namely, we get the following equality $ lim_{jto infty} UC_B(psi^P_j) = lim_{jto infty}UC_H(psi^N_j), $ where $UC_B$ and $UC_H$ are the Breitenberger and the Heisenberg uncertainty constants, $psi^P_j in L_2(mathbb{T})$ and $psi^N_jin L_2(mathbb{R})$ are periodic and nonstationary wavelet functions respectively.

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