Exact Solution to Electromagnetic Scattering by an Impedance Sphere Coated With a Uniaxial Anisotropic Layer

Abstract

Abstract-Electromagnetic fields in uniaxial anisotropic media can be obtained based on spherical vector wave functions in isotropic media. Applying the boundary conditions of electromagnetic fields on each interface of an impedance sphere coated with a uniaxial anisotropic layer, the expansion coefficients of electromagnetic fields in the uniaxial anisotropic medium and free space can be derived. The present method is very general, which can be reduced to many isotropic subcases. The present method has been validated in those subcases. Scattering by an impedance sphere with an anisotropic coating is presented and discussed.Index Terms-Anisotropy ratio, electromagnetic scattering, impedance sphere, spherical vector wave functions, uniaxial anisotropic media.

Anisotropic Scattering Characteristics of a Radially Multilayered Gyrotropic Sphere

“…Four cases with different electrical dimensions are depicted in Figure 4. It can be seen that the truncated series converge well when the summation index is truncated at the value given by (15), and the convergence accuracy is at least 10 −5 . To verify the correctness of the formulations derived for the multilayered gyrotropic sphere in this paper, two numerical experiments are conducted.…”

“…The convergence criteria (15) are commonly used for homogeneous spherical scatterers [35,36]. As for the gyrotropic case considered in this work, the validation of truncation number has been checked by computing the relative error of truncated series of the scattering efficiency factor sca = (4/ sca is the truncated series and sca is the converged value (calculated for a sufficiently large ).…”

“…For studying the interactions of EM waves and gyrotropic media, the most important and challenging task is to solve the vector wave equation characterizing EM fields in gyrotropic media. In the last several decades, a few analytical approaches have been developed based on the Cartesian coordinate expression of permittivity and permeability tensors, such as the perturbation expansion method [10,11], the method of expanding EM fields in gyrotropic media using a complete set of VSWFs [12], the method of adopting VSWFs combined with Fourier transform [13][14][15], dyadic Green's functions method [16][17][18], and the -matrix method [19][20][21][22][23]. To study the spherical anisotropy, Qiu et al have investigated the characteristics of radial anisotropic uniaxial and gyrotropic sphere, where the permittivity and permeability tensors are expressed in spherical coordinate [24][25][26][27][28][29][30].…”

Study on the Properties of Surface Waves in Coated Ram Layers and Monostatic RCSR Performances of the Coated Slab

“…Therefore, it is desirable to study the properties of surface waves in coated RAM layers and mono-static RCSR performances of the coated slab. In the past researches of RCSR of a target using RAM, some important electromagnetic scattering problems including the quantitative interrelationships between the coating materials sorts, coating layers, coating thickness and the shaping design such as curvature adjustment, have been extensively investigated by M. Hossein [5], F. C. Smith [6], You-lin Geng [7], et al. Yet the intrinsic electromagnetic characteristics of the coated RAMs are rarely concerned.…”

The Role of Anisotropy Ratio in Backscattering of Spherically Anisotropic Particles: An Analytical Electromagnetic Characterization

“…However, the macroscopic anisotropic response from the ordering of thin oriented molecules on a small spherical particle has received less attention in spite of its importance in the technologies of the embedding of artificial particles and detection of molecules with abnormal protein. A few methods, such as Fourier transform and Mie theory, have been utilized to study the anisotropy's role in the scattering where the anisotropy is defined in Cartesian coordinates [10,11]. However, those methods lead to the complexity in formulating electromagnetic fields in a 3D particle made of orientated molecules whose anisotropy is along radial direction [12][13][14].…”