PHENOMENOLOGICAL DESCRIPTION OF THE SURFACE COHERENT IMAGE IN THE OPTICAL-ELECTRONIC AND RADIO ENGINEERING SYSTEMS OF REMOTE SENSING

Abstract

The basic principles of the scalar theory of diffraction, Huygens-Fresnel principle and fundamental theorems of calculation of the field in any point of volume according to the field and its first derivative on the surface encloses this volume are analyzed. It follows from the analysis that the general definition of the coherent image is Kirchhoff boundary conditions, in other words the spatial distributed boundary conditions specified in the form of continuous functions of spatial coordinates of the field on a surface with continuous first and second derivatives. The specification of these conditions for real terrestrial covers, such as roughness surfaces or two-scale surfaces, considerably complicates the solution of diffraction problems. That is why the phenomenological description of the scattered fields is suggested. The examples of phenomenological definition of the field in Fresnel and Fraunhofer zones are given. It's shown that complete recovery of coherent images can be achieved by applying inverse transforms with infinitive limits of integration. However infinite limits can't be provided even for the big sizes of scattering and receiving areas. The process of coherent images recovery in radio engineering system with finite antenna size is shown and limit resolution of such images is analyzed. Both recovered images, in Fresnel and Fraunhofer zones, have the same Green function. This fact corresponds to the theory of resonant scattering.