Fourier frames

We solve the problem of Duffin and Schaeffer (1952) of characterizing those sequences of real frequencies which generate Fourier frames. Equivalently, we characterize the sampling sequences for the Paley-Wiener space. The key step is to connect the problem with de Branges' theory of Hilbert spa...

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Detalles Bibliográficos
Autores: Ortega Cerdà, Joaquim, Seip, Kristian
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2002
País:España
Institución:Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya)
Repositorio:Recercat. Dipósit de la Recerca de Catalunya
OAI Identifier:oai:recercat.cat:2445/164422
Acceso en línea:https://hdl.handle.net/2445/164422
Access Level:acceso abierto
Palabra clave:Anàlisi harmònica
Funcions de variables complexes
Funcions analítiques
Anàlisi funcional
Harmonic analysis
Functions of complex variables
Analytic functions
Functional analysis
Descripción
Sumario:We solve the problem of Duffin and Schaeffer (1952) of characterizing those sequences of real frequencies which generate Fourier frames. Equivalently, we characterize the sampling sequences for the Paley-Wiener space. The key step is to connect the problem with de Branges' theory of Hilbert spaces of entire functions. We show that our description of sampling sequences permits us to obtain a classical inequality of H.~Landau as a consequence of Pavlov's description of Riesz bases of complex exponentials and the John-Nirenberg theorem. Finally, we discuss how to transform our description into a working condition by relating it to an approximation problem for subharmonic functions. By this approach, we determine the critical growth rate of a non-decreasing function $\psi$ such that the sequence $\{\lambda_k\}_{k\in\Z}$ defined by $\lambda_k+\psi(\lambda_k)=k$ is sampling.