Super Fresnel resolution of phase screen fine structure: tomography-like approach

Abstract

In this paper we study the small scale inhomogeneities at the thin 1D phase screen, using weighted Fourier transform (WFT), which contains quadratic in phase weighted function and represents a simplified version of double weighted Fourier transform (DWFT), suggested earlier [1,2]. The phase screen is assumed to be illuminated by the point source, and the wave field, scattered by the phase screen, is measured by the set of receivers. Integral, performing weighted Fourier transform is shown to contain delta-like function, which localizes inhomogeneities at the thin phase screen and allows their reconstructing. Such tomography-like measurement scheme is shown to provide super Fresnel resolution, close to diffraction limit. These results may serve as basis for developing 2D and 3D tomography system in IR or microwave bands for studying small-scale turbulent inhomogeneities in thermonuclear devices like tokamaks and stellarators.