Electromagnetic Scattering from Periodic Arrays of Two Circular Cylinders Per Unit Cell

Abstract

A very efficient and accurate method to characterize the electromagnetic scattering from periodic arrays of two-dimensional composite cylindrical objects with internal eccentric cylindrical scatterers is presented, using the lattice sums formula and the aggregate T-matrix for cylindrical structures. The method is quite general and applies to various configurations of two-dimensional periodic arrays. The dielectric host cylinder per unit cell of the array can contain two or more eccentric cylindrical scatterers (we call them inclusions in this paper), which may be dielectric, conductor, gyrotropic medium, or their mixture with different sizes. The power reflection coefficients from one-layer or one-hundred-layered periodic arrays of composite cylinders with up to two inclusions have been numerically studied. The effect of the presence of inclusions on the properties of resonance peaks or the stopband's width will be discussed.

Electromagnetic Scattering From Periodic Arrays of Composite Circular Cylindrer With Internal Cylindrical Scatterers

“…Using the recurrence formula and Fourier integral representation for Hankel functions, the scattered field can be finally obtained in terms of the Floquet space-harmonic waves in the xOy coordinate system. After several manipulations, the reflected field Ψ r l (x, y) of the l-th space-harmonic in the upper half-space y > 0 and the corresponding transmitted field Ψ t l (x, y) in the lower half-space y < 0 for downgoing incident plane wave are deduced as follows [8]:…”

Hybrid Technique for the Analysis of Scattering From Periodic Structures Composed of Irregular Objects

“…In order to determine these parameters the investigated structure is divided into layers (surfaces for a fixed y) which constitute two dimensional (2D) periodic FSSs. Each layer can be described by a multimodal scattering matrix, which relates the incident space-harmonics to the scattered, both reflected and transmitted ones, utilizing authors' technique [22] based on an efficient numerical technique described in [18,23,24]. Assuming the surface periodic in x and z directions the fields consist of set of space harmonics and the z components of the incident and scattered fields can be described as follows:…”

“…The most popular are the cylindrical-harmonic expansion method [18], the finite element method [19], the finitedifference method [20], and Fourier modal method [21]. Here we calculate the scattering parameters of periodic arrangements of metalodielectric or ferrite scatterers assuming a plane wave excitation of the structure.…”

“…In order to obtain the scattering parameters we first calculate the multimodal scattering matrices of each layer (each FSS), utilizing authors' numerical technique [22], and then use cascading formulas to obtain the results for the entire structure. The proposed approach utilizes an efficient numerical technique described in [18,23,24], which is based on the transmission matrix (T-matrix) method [25] and uses the lattice sums technique [26]. The obtained scattering matrix relates the incident space-harmonics to the scattered, both reflected and transmitted ones.…”

Two-Dimensional Electromagnetic Scattering of Non-Plane Incident Waves by Periodic Structures

“…Here we use a calculation technique of RTMA developed by Roussel [10] and Yasumoto et al [11][12][13][14] to derive the T-matrices of periodic cylinder array for plane wave incidence. Following these methods, the scattering relation of the wave amplitudes is calculated in the following form…”