83 citations · 515 across the 58 of their papers we have counts for
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Time-Frequency Partitions and Characterizations of Modulation Spaces with Localization Opertors
Monika Doerfler, Karlheinz Groechenig
We study families of time-frequency localization operators and derive a new characterization of modulation spaces. This characterization relates the size of the localization operat…
Frame Constants of Gabor Frames near the Critical Density
A. Borichev, K. Gröchenig, Yu. Lyubarskii
We consider Gabor frames generated by a Gaussian function and describe the behavior of the frame constants as the density of the lattice approaches the critical value.
Representation and Approximation of Pseudodifferential Operators by Sums of Gabor Multipliers
Karlheinz Groechenig
We investigate a new representation of general operators by means of sums of shifted Gabor multipliers. These representations arise by studying the matrix of an operator with respe…
Isomorphism properties of Toeplitz operators and pseudo-differential operators between modulation spaces
Karl-Heinz Gröchenig, Joachim Toft
We investigate the lifting property of modulation spaces and construct explicit isomorpisms between them. For each weight function and suitable window function $\fy $, the Toep…
Noncommutative Approximation: Inverse-Closed Subalgebras and Off-Diagonal Decay of Matrices
Karlheinz Gröchenig, Andreas Klotz
We investigate two systematic constructions of inverse-closed subalgebras of a given Banach algebra or operator algebra A, both of which are inspired by classical principles of app…