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arXiv · 2401.12387

Coorbit Theory for Coefficients in Weighted Lebesgue Spaces, and its Application to the Wavelet Transform and the Short-Time Fourier Transform

Jan Zimmermann
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Abstract

Starting with an integrable unitary representation of a locally compact group and its associated voice transform, coorbit theory describes the construction and investigation of the so-called coorbit spaces. A coorbit space consists of distributions of which the voice transform is contained in a given function space. We construct coorbit spaces which elements have voice transforms in weighted Lebesgue spaces. By applying this construction to the wavelet transform and short-time Fourier transform, we obtain special cases of the homogeneous Besov spaces and the modulation spaces, respectively. We also discretize the coorbit spaces in terms of Banach frames, where the frame vectors are contained in the orbit of some suitable element under the group action. For the two examples of the wavelet transform and the short-time Fourier transform, we derive sufficient conditions for a wavelet respectively a Gabor window to be suitable to generate such a Banach frame in the respective context.

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Jan Zimmermann. 2024-01-22. Coorbit Theory for Coefficients in Weighted Lebesgue Spaces, and its Application to the Wavelet Transform and the Short-Time Fourier Transform. https://arxiv.org/abs/2401.12387

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