TW 477

Steven Delvaux, Marc Van Barel
Rank-deficient submatrices of Kronecker products of Fourier matrices

Abstract

We provide a set of maximal rank-deficient submatrices of a Kronecker product of two matrices AB$, and in particular the Kronecker product of Fourier matrices F=Fn1⊗...⊗ Fnk. We show how in the latter case, maximal rank-deficient submatrices can be constructedas tilings of rank-one blocks. Such tilings exist for any subgroup of a suitable Abelian group associated to the matrix F. These maximal rank-deficient submatrices are also related to an uncertainty principle for Fourier transforms over finite Abelian groups, for which we can then obtain stronger versions.

report.pdf (375K) / mailto: M. Van Barel