General approach to the line source electromagnetic scattering by a circular strip: Both E‐ and H‐polarisation cases

Abstract

This study presents a new approach to line-source diffraction by a circular strip. The investigation is obtained by employing both electric and magnetic line sources where the corresponding field components satisfy the Dirichlet and Neumann boundary conditions. The position of the line source in the problem resulted in a very different radiation mechanism. Regarding the boundary condition and the aperture size, the total field characteristics change noticeably. The current density on the circular strip is expressed by Fourier series expansion, and then, orthogonal polynomials including edge condition are utilised to obtain the scattered field. The investigation is done throughout the far-field radiation pattern, near-field distributions, and the total radar cross-section. Then, the results are compared with the analytical and numerical outcomes. For the comparison, the method of moments and the method of auxiliary sources are employed as the numerical tools.

H‐polarized plane wave diffraction by a slotted cylinder with different surface impedances: Solution by the analytical—Numerical approach

“…The edge conditions are satisfied by choosing the proper values of $${\nu }_{1}$$ and $${\nu }_{2}$$ as $${\nu }_{1}=-0.5$$ and $${\nu }_{2}=0.5$$ [13]. Due to having periodicity in $$\phi $$, the Fourier series expansion is achieved as follows [7, 16]: $$${\mu }_{m}^{e}=\frac{\pi \varepsilon }{2\mathrm{j}}\frac{\theta }{{\Gamma}({\nu }_{1}+\frac{1}{2})}\sum\limits _{n=0}^{\infty }{\mathrm{j}}^{n}{x}_{n}{\beta }_{n}^{{\nu }_{1}+\frac{1}{2}}\frac{{J}_{{\nu }_{1}+n+\frac{1}{2}}(-m\theta )}{{(-2m\t...$$…”

“…The edge conditions are satisfied by choosing the proper values of ν 1 and ν 2 as ν 1 ¼ −0:5 and ν 2 ¼ 0:5 [13]. Due to having periodicity in ϕ, the Fourier series expansion is achieved as follows [7,16]:…”

Electromagnetic Scattering from 2-D Conducting Objects with Arbitrary Smooth Shape: Complete Mathematical Formulation of the Method of Auxiliary Sources for E-polarized Case

“…Here, S stands for the actual surface of the scatterer, and S aux corresponds to the auxiliary surface where the current density induced on the actual surface is shifted d amount to eliminate the singularity problem. As it is known from Maxwell's equation, it is possible to express the scattered electric field in terms of Green's function convolved with the current density on the scatterer in the case of TM polarization as given in (1). It should be noted that the time dependency is e −iωt and omitted throughout the study.…”

“…Electromagnetic scattering and the behavior of electromagnetic waves in the vicinity of obstacles have always been of crucial importance in science and engineering [1]. Since electromagnetic waves are employed for noninvasive detection, radar applications, antenna design, and characterization of materials and surfaces with different electromagnetic or periodic properties, numerous analytical, numerical, or analytical-numerical approaches have been developed [2][3][4][5][6].…”

Electromagnetic scattering of H‐polarised cylindrical wave by a double‐sided impedance circular strip

“…As a result, two-dimensional problems play a critical role in the initial validation of the proposed methodology or design [8]. The study points out that previous studies have primarily focused on various geometries, boundary conditions, sources, polarisations, surface characteristics and edge conditions in two-dimensional scattering problems [9][10][11][12][13][14][15]. Traditionally, the perfect electric and magnetic conducting surfaces have been studied with the Dirichlet and Neumann boundary conditions, respectively [16].…”