Through-wall electromagnetic scattering by N conducting cylinders

Abstract

A spectral-domain analysis is presented for the scattering by perfectly conducting cylindrical objects behind a dielectric wall. The solution is developed with an analytical-numerical technique, based on the cylindrical wave approach. Suitable cylindrical functions and their spectral representations are introduced as basis functions for the scattered fields, to deal with their interaction with the planar interfaces bounding the wall. The numerical solution is given in TE and TM polarizations states, and in both near- and far-field zones. The model yields an accurate computation of direct scattering that can be useful for through-wall-imaging applications. A stack of three different dielectric media is considered in the theoretical model. In the numerical results, the upper medium, where the incident field is generated, is assumed to be filled by air, the central layer represents the wall, and the lower medium, which contains the scatterers, is air filled, too. Also general problems of scattering by buried objects can be simulated, being the cylinders buried in a medium of arbitrary permittivity, placed below a dielectric layer.

The Cylindrical Wave Approach for the Electromagnetic Scattering by Targets behind a Wall

“…The second is a right-propagating wave, which from medium 0 is scattered back in medium 2, through the fields sr V 2 and sr V 1 . This compact decomposition, presented in detail in [20], leads to a faster approach to the solution of the scattering problem, compared to the one of Figure 2b [19]. In the latter, all the possible interactions of the scattered fields inside the boundary are taken into account, through multiple reflection fields strt…”

“…Such fields are given by infinite and convergent series, which are truncated to a finite number of terms in the numerical implementation depending on the desired accuracy. Decomposition of the scattered fields in the scattering by targets in a through-wall environment: (a) non-iterative approach [19] and (b) iterative approach [20].…”

“…In both approaches in [19,20], the scattered field V s in medium 2 by the cylinders can be defined through an expansion into cylindrical functions of m-th order:…”

A Hybrid Asymptotic-FVTD Method for the Estimation of the Radar Cross Section of 3D Structures

“…Several electromagnetic problems require solvers able to characterize complex and multi-scale structures [1][2][3][4]. To this end, two main classes of approaches can be identified.…”

Simulation of scattering by cylindrical targets hidden behind a layer

“…Through a multiple-reflection ap proach, the method has been extended also to a layered geometry, with scatterers embedded into dielectric slab [11] [12]. The same approach has also turned out to be suitable to deal with the modeling of scattering by objects below a dielectric layer, in the frame of TW problems [13]. Ac cording to the CWA fundamentals, the field radiated by the hidden objects is expanded into cylindrical functions, and its interaction with the interfaces bounding the upper layer is accounted for by multiple reflections, through an infinite and convergent series.…”