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arXiv · 1511.04007

Separation of zeros and a Hermite interpolation based frame algorithm for band limited functions

A. Antony Selvan·R. Radha
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Abstract

It is shown that if a non-zero function $f\in B_σ$ has infinitely many double zeros on the real axis, then there exists at least one pair of consecutive zeros whose distance apart is greater than $\dfracπστ^{1/4}$, $τ\approx5.0625$. A frame algorithm is provided for reconstructing a function $f\in B_σ$ from its nonuniform samples $\{f^{(j)}(x_i):j=0,1,\dots, k-1, i\in\mathbb{Z}\}$ with maximum gap condition, $\sup\limits_i(x_{i+1}-x_i)=δ<\dfrac{1}σc_k^{1/2k}$, where $c_k$ is a Wirtinger-Sobolev constant, using Hermite interpolation.

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A. Antony Selvan, R. Radha. 2015-11-02. Separation of zeros and a Hermite interpolation based frame algorithm for band limited functions. https://arxiv.org/abs/1511.04007

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