A Complex Geometric Approach to the Discrete Gabor Transform and Localization Operators on the Flat Torus

Abstract

In a recent paper, the discrete Gabor transform was connected to a Gabor transform with a time frequency domain given by the flat torus. We show that the corresponding Bargmann-Fock spaces can be expressed as theta functions (or equivalently line bundles on Abelian varieties). We give applications of this viewpoint to frame results for the discrete Gabor transform. In particular, we get necessary conditions which hold in higher dimensions and can expand the known results in the one dimensional case, the primary tool being the theorem of the square. We also give an application to asymptotics of restriction operators which arises via the asymptotic behavior of Bergman kernels and Toeplitz operators for high tensor powers of line bundles and find that discrete time frequency restriction operators will exhibit "plunge" behaviors similar to those of time frequency restriction operators in other contexts.

arXiv comment24 pages, 3rd version, Theorem B has been changed from the last version