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    <journal-meta>
      <journal-id journal-id-type="nlm-ta">reapress</journal-id>
      <journal-id journal-id-type="publisher-id">null</journal-id>
      <journal-title>reapress</journal-title><issn pub-type="ppub">3042-3058</issn><issn pub-type="epub">3042-3058</issn><publisher>
      	<publisher-name>reapress</publisher-name>
      </publisher>
    </journal-meta>
    <article-meta>
      <article-id pub-id-type="doi">https://doi.org/10.48314/isti.vi.54</article-id>
      <article-categories>
        <subj-group subj-group-type="heading">
          <subject>Research Article</subject>
        </subj-group>
        <subj-group><subject>Shannon sampling, Generalized sinc function, Blaschke product, Ladder shaped filter.</subject></subj-group>
      </article-categories>
      <title-group>
        <article-title>Generalized sinc Functions from Rational Functions and Applications in Signals</article-title><subtitle>Generalized sinc Functions from Rational Functions and Applications in Signals</subtitle></title-group>
      <contrib-group><contrib contrib-type="author">
	<name name-style="western">
	<surname>Niu</surname>
		<given-names>Sen </given-names>
	</name>
	<aff>Department of Mathematics, College of Mathematics and Informatics, South China Agricultural University, Guangzhou, China.</aff>
	</contrib></contrib-group>		
      <pub-date pub-type="ppub">
        <month>12</month>
        <year>2025</year>
      </pub-date>
      <pub-date pub-type="epub">
        <day>07</day>
        <month>12</month>
        <year>2025</year>
      </pub-date>
      <volume>2</volume>
      <issue>4</issue>
      <permissions>
        <copyright-statement>© 2025 reapress</copyright-statement>
        <copyright-year>2025</copyright-year>
        <license license-type="open-access" xlink:href="http://creativecommons.org/licenses/by/2.5/"><p>This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.</p></license>
      </permissions>
      <related-article related-article-type="companion" vol="2" page="e235" id="RA1" ext-link-type="pmc">
			<article-title>Generalized sinc Functions from Rational Functions and Applications in Signals</article-title>
      </related-article>
	  <abstract abstract-type="toc">
		<p>
			The classical Shannon sampling theorem applies exclusively to bandlimited signals. This paper extends the theory to a class of non-bandlimited signals that still permit exact uniform sampling. We introduce a ladder-shaped filter with m real parameters, whose impulse response is a generalized Sinc function obtained from finite Blaschke products. For the corresponding signal space, we establish a generalized sampling theorem that reconstructs any signal from its samples {f(nπ/Ω)}n∈Z using the multi-parameter generalized Sinc kernel. Additionally, we prove that these signals can be analytically extended to a strip in the complex plane, generalizing the Paley–Wiener theorem to the non-bandlimited setting. The proposed framework bridges the gap between classical bandlimited theory and practical non-bandlimited signals, providing both theoretical foundations and tools for signal processing applications.
		</p>
		</abstract>
    </article-meta>
  </front>
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