Perturbations and Irregular Sampling Theorems for Frames
نویسندگان
چکیده
This paper gives a perturbation theorem for frames in a Hilbert space which is a generalization of a result by Casazza and Christensen. Then this result is applied to the Perturbation of regular sampling in shift-invariant spaces. Irregular sampling theorems for frames in wavelet subspaces are established for which it is easy to derive explicit formulas and algorithms to calculate the ranges of the perturbations for frames. Furthermore, improved estimates for the Perturbations are derived for the Perturbations of regular sampling in shift-invariant spaces.
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