I.Yu. Bratukhin1, Ye.G. Gladkikh2, A.F. Kryachko3

1–3 St. Petersburg State University of Aerospace Instrumentation (St. Petersburg, Russia)

1 JSC «Concern «Automatika» (Moscow, Russia)

3 alex_k34.ru@mail.ru

To solve a number of practical problems related to the identification of defects and damages in materials, the establishment of the state of structures, the identification of inhomogeneities in optically impermeable media and visualization of their structure, it is necessary to process information obtained remotely, which requires an assessment of the material parameters of the objects of study and establish their spatial distribution. The aim of the work is to increase the efficiency of means for estimating the parameters of inhomogeneous media based on the known distribution of the scattered electromagnetic field by solving the inverse scattering problem.

The paper considers a method for solving the inverse problem of scattering by reflection coefficient for lossless multilayer structures, the high accuracy of which is achieved due to a finite number of coefficients of Jost solutions, which makes it possible to avoid calculating coefficients of unlimited trigonometric sequences in the elements of the scattering matrix. The results obtained made it possible to estimate the number of layers of the dielectric structure, to determine the dielectric constant and the width of each layer according to the values of the complex reflection coefficient, which is known from the results of measurements at a discrete set of frequencies in a limited range. The data obtained is sufficient for the analysis of dielectric materials by the non-destructive method and the identification of stratification and deviation of layer parameters from technologically specified values. A method for determining the distribution of the dielectric constant along the transverse coordinate in dielectric planar layered structures has been developed. Algorithms for the identification of interface surfaces by the reflection coefficient of a normally incident plane wave have been developed, which are used as signal processing procedures in subsurface radar, which avoids false detection of inhomogeneities when analyzing the structure of media.

Bratukhin I.Yu., Gladkikh Ye.G., Kryachko A.F. Inverse scattering problem for a layered dielectric based on the values of the measured parameters. Achievements of modern radioelectronics. 2025. V. 79. № 8. P. 6–20. DOI: https://doi.org/10.18127/j20700784-202508-01 [in Russian]

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