4 papers · 1 filter
Gabor Frames of Totally Positive Functions: A Complete Characterization
Jaume de Dios Pont, Karlheinz Gröchenig, Lukas Liehr +2
We prove that the set of time-frequency shifts with a continuous, integrable totally positive function and lattice parameters $α…
A Characterization of Metaplectic Time-Frequency Representations
Karlheinz Gröchenig, Irina Shafkulovska
We characterize all time-frequency representations that satisfy a general covariance property: any weak*-continuous bilinear mapping that intertwines time-frequency shifts on the c…
Geodesic cycles on the Sphere: -designs and Marcinkiewicz-Zygmund Inequalities
Martin Ehler, Karlheinz Gröchenig, Clemens Karner
A geodesic cycle is a closed curve that connects finitely many points along geodesics. We study geodesic cycles on the sphere in regard to their role in equal-weight quadrature rul…
Benedicks-type uncertainty principle for metaplectic time-frequency representations
Karlheinz Gröchenig, Irina Shafkulovska
Metaplectic Wigner distributions are joint time-frequency representations that are parametrized by a symplectic matrix and generalize the short-time Fourier transform and the Wigne…