Multiscale estimates for the condition number of non-harmonic Fourier matrices

Weilin Li

This paper studies the extreme singular values of non-harmonic Fourier matrices. Such a matrix of size $m\times s$ can be written as $Φ=[ e^{-2πi j x_k}]_{j=0,1,\dots,m-1, k=1,2,\d…