English

On stable reconstructions from nonuniform Fourier measurements

Numerical Analysis 2014-04-08 v2

Abstract

We consider the problem of recovering a compactly-supported function from a finite collection of pointwise samples of its Fourier transform taking nonuniformly. First, we show that under suitable conditions on the sampling frequencies - specifically, their density and bandwidth - it is possible to recover any such function ff in a stable and accurate manner in any given finite-dimensional subspace; in particular, one which is well suited for approximating ff. In practice, this is carried out using so-called nonuniform generalized sampling (NUGS). Second, we consider approximation spaces in one dimension consisting of compactly supported wavelets. We prove that a linear scaling of the dimension of the space with the sampling bandwidth is both necessary and sufficient for stable and accurate recovery. Thus wavelets are up to constant factors optimal spaces for reconstruction.

Keywords

Cite

@article{arxiv.1310.7820,
  title  = {On stable reconstructions from nonuniform Fourier measurements},
  author = {Ben Adcock and Milana Gataric and Anders C. Hansen},
  journal= {arXiv preprint arXiv:1310.7820},
  year   = {2014}
}