Perfect Electric Conductor Plane Research Articles

Scattering from a semi‐elliptical cavity with arbitrary orientation placed in a perfect electric conductor plane

AbstractA semi‐analytic solution for scattering from a semi‐elliptical cavity with arbitrary orientation placed in a perfect electric conductor plane is suggested. By imposing the boundary conditions at an elliptical border, three independent equations containing the Mathieu functions series are extracted. Finally, the solution of the problem is reduced to the solution of a simple system of linear equations by using Mathieu function addition theorem and the orthogonal properties of the angular Mathieu functions. Some examples are presented to demonstrate the reliability and the accuracy of the proposed solution.

TM Scattering by a Shallow Elliptical-Shaped Cavity

In this letter, the problem of electromagnetic scattering by a shallow elliptical-shaped cavity in a perfect electric conductor plane is considered. We propose an efficient modal approach based on the region-matching technique that can calculate scattered fields without the use of the Mathieu functions. By enforcing boundary conditions at a semicircular auxiliary border, a system of linear equations is constructed. The results obtained by this method are compared with those provided by the method of moment. Finally, the effect of the shape of the cavity on the scattering signature is investigated.

Loop-to-Loop Magnetic Coupling Through a Circular Aperture in a Planar PEC Screen of Finite Thickness

An analytical formulation for magnetic field penetration through a circular aperture in a thin perfect electric conductor (PEC) screen with finite-thickness is developed. Especially, we propose an analytical formula for the magnetic coupling between two circular loops separated by the screen and placed coaxially with the aperture. The formula is verified by finite element simulations and experimental data. The thickness effect is explained by the cut off attenuation of TE01 mode in the aperture. The influences of loop-screen-loop distance and loop radius on the coupling intensity are also investigated.

Semi-analytical solution of electromagnetic scattering of a slit in PEC plane located in TI medium

The electromagnetic scattering of a slit in the perfect electric conductor (PEC) plane embedded in the topological insulator (TI) medium is analyzed in this paper. The problem is solved by utilizing Kobayashi Potential method, which is a rapid semi-analytical approach with decent accuracy. In solving process, scattered fields are consist of some variables known as weighting functions. By applying boundary conditions, unknowns will be found. Also, discontinuous properties of Weber-Schafheitlin integrals and Rodriguez representation of Jacobi polynomials are employed to satisfy some of the boundary conditions and edge conditions of the problem simultaneously. By performing convergence analysis and error analysis, validation of the proposed approach is confirmed. Finally, by sweeping some parameters, the scattering behavior of the structure is investigated.

Near-field effects on partially coherent light scattered by an aperture

We investigate how the near field affects partially coherent light scattered from an aperture in an opaque screen. Prior work on this subject has focused on the role of surface plasmons, and how they affect spatial coherence is well documented. Here, we consider other near-field effects that might impact spatial coherence. We do this by examining the statistics of the near-zone field scattered from an aperture in a perfect electric conductor plane—a structure that does not support surface plasmons. We derive the near-field statistics (in particular, cross-spectral density functions) by applying electromagnetic equivalence theorems and the Method of Moments. We find, even in the absence of surface plasmons, that near-field physics can affect the coherence of the scattered field. The analysis and findings presented herein complement the existing coherence-related surface plasmons literature, and could find use in the design of photonic devices built to engineer spatial coherence.

High isolation circularly polarized (CP) antennas using compact soft surface

ABSTRACTA compact soft surface is proposed to improve an isolation of circularly polarized patch antennas in this article. The soft surface is generally made up of a periodically alternating perfect electric conductor and perfect magnetic conductor. The perfect magnetic conductor is implemented by the corrugation with a depth of quarter wavelength. The proposed compact soft surface is designed by a folded corrugation with a length of a quarter wavelength and the folded part is located below perfect electric conductor plane. Thus, the compact soft surface can be designed without any additional area above the ground plane. To verify its feasibility, mutual coupling and axial ratio of two circularly polarized antenna elements without and with the compact soft surface have been compared. This improved isolation results in small active reflection coefficient and wide beamwidth of active element pattern which would help to design wide scanning angle array.

Carpet Cloak Design for Rough Surfaces

Conventional carpet cloak structures have been utilized to conceal the objects located on a planar perfect electric conductor surface. We systematically investigate hiding arbitrarily shaped objects on a rough surface, as a more general and practical scenario. In addition, the required cloak is designed considering different boundary conditions for the surface beneath the object, despite the previous studies. To achieve an invisibility cloak, taking advantage of linear coordinate transformation, a simple homogeneous material is obtained to realize the cloak structure, facilitating the fabrication processes. Numerical simulations validate the performance of the proposed cloaking method. Therefore, the proposed structure is capable of cloaking in more general and complicated scenarios.

Spoof Surface Plasmon Polariton Leaky-Wave Antennas Using Periodically Loaded Patches Above PEC and AMC Ground Planes

This paper proposes two spoof surface plasmon polariton (SSPP) leaky-wave antennas using periodically loaded patches above perfect electric conductor (PEC) and artificial magnetic conductor (AMC) ground planes, respectively. The SSPP leaky-wave antenna is based on a SSPP transmission line, along which circular patches are periodically loaded on both sides to provide an additional momentum for phase matching with the radiated waves in the air. The PEC and AMC ground planes underneath the antenna reflect the radiated waves into the upward space, leading to an enhanced radiation gain. Both PEC- and AMC-grounded antenna prototypes are fabricated and measured in comparison with the one without any ground plane. The experimental results show that the PEC and AMC ground planes increase the radiation gain by approximately 3 dB within the operational frequency range 4.5-6.5 GHz. It also demonstrates that the AMC-grounded leaky-wave antenna, with a thickness of 0.08\lambda at 6 GHz, features more compact profile than the PEC-grounded one (with a thickness of 0.3\lambda at 6 GHz).

Metal Grid Mesh 인쇄를 이용한 투명 전파 흡수구조 설계

ABSTRACT In this paper, we designed the transparent circuit analog radar absorbing structure using printed metal grid mesh for enhanced optical transmittance. To obtain wideband electromagnetic absorption and enhanced optical transparency at X-band, we proposed the resistive FSS(Frequency Selective Surface) using printed metal mesh pattern on transparent glass with PEC(Perfect Electric Conductor) plane using ITO(Indium Thin Oxide) coating. We then fabricated the proposed structure to verify the simulation results obtained from commercial EM simulator. The comparisons between the simulation and measured results show good agreements. The results also show that the proposed radar absorbing structure can provide wideband reflection as well as better optical transparency. We can apply this proposed structure to the canopy of stealth aircraft and other stealth and security applications for visible transparency.Key Words : Electromagnetic Absorbing Structure(전파 흡수구조), Frequency Selective Surface(주파수 선택표면구조), Metal mesh(메탈 메쉬), Optical Transmittance(광투과율)

High-Contrast Gratings based Spoof Surface Plasmons.

In this work, we explore the existence of spoof surface plasmons (SSPs) supported by deep-subwavelength high-contrast gratings (HCGs) on a perfect electric conductor plane. The dispersion relation of the HCGs-based SSPs is derived analyt- ically by combining multimode network theory with rigorous mode matching method, which has nearly the same form with and can be degenerated into that of the SSPs arising from deep-subwavelength metallic gratings (MGs). Numerical simula- tions validate the analytical dispersion relation and an effective medium approximation is also presented to obtain the same analytical dispersion formula. This work sets up a unified theoretical framework for SSPs and opens up new vistas in surface plasmon optics.

13.56 MHz 무선 에너지 전송 시스템의 효율적인 전자파 장해(EMI) 예측 및 분석 방법

The effective way of estimation and analysis of EMI(Electromagnetic Interference) in Wireless Power Transfer System operating at 13.56 MHz is proposed. In this paper methodology of driving magnetic field strength and electric loop current of two antennas which are in free space and on PEC plane using image theory and duality is proposed. Perfect electric conductor(PEC) is planar, infinite in extent, and perfectly conducting plane. And we will refer it as PEC plane. A equivalent circuit model is used to analyze. Using this theoretical analysis, we can derive maximum magnetic field strength of the far-field region numerically using measured data of near-field maximum magnetic field strength. The experimental results using commercial numerical simulation tool are in agreement with the theoretical results. Also, using the derivation of maximum magnetic field strength in the far-field region, we can easily estimate the maximum allowable power dissipation that meets EMI regulations.

Theory of aperture-coupled hemispherical dielectric resonator antennas with radiating elements

A new approach based on hybrid volume-surface integral equation (VSIE) formulation in combination with spherical dyadic Green's function (DGF) is presented in this paper to analyze aperture-coupled multilayer hemispherical dielectric resonator antennas (DRA) with conformal conducting patches. Hybrid VSIE is used for the planar part of the structure and is solved with the aid of spatial-domain method of moments (MoM) in order to compute magnetic surface current in a slot cut in a finite planar perfect electric conductor (PEC) sheet. Multilayer spherical electromagnetic DGFs are used to compute loading effects of hemispherical dielectric resonators and conformal patches on antenna characteristics. The effects of variation in some parameters of the structure on the return loss of the antenna are studied. Accuracy of the presented method is validated by comparing the results obtained from the proposed method with those of CAD simulations.

Propagation of designer surface plasmons in structured conductor surfaces with parabolic gradient index

In this work, we investigate the propagation of designer surface plasmons in planar perfect electric conductor structures that are subject to a parabolic graded-index distribution. A three-dimensional, fully vectorial finite-difference time-domain method was used to engineer a structure with a parabolic effective group index by modulating the dielectric constant of the structure's square holes. Using this structure in our simulations, the lateral confinement of propagating designer surface plasmons is demonstrated. Focusing, collimation and waveguiding of designer plasmons in the lateral direction is realized by changing the width of the source beam. Our findings contribute to applications of designer surface plasmons that require energy concentration, diffusion, guiding, and beam aperture modification within planar perfect electric conductors. .

Experimental and Theoretical Validation for the Incremental Theory of Diffraction

<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> Experimental and theoretical approaches to verify the validity of the incremental theory of diffraction (ITD) are considered. After providing a simple recipe for the application of the ITD, three geometries are examined for its validation. First, the ITD formulation of the diffraction from a perfect electric conductor (PEC) straight wedge is compared with the uniform theory of diffraction (UTD) and with measurement results. Second, the ITD formulation of the diffraction from a PEC disc is compared with measurement results and with the exact solution of a boundary value problem involving oblate spheroidal functions. Third, the ITD formulation of the diffraction from a hole in a PEC plane is compared with the exact solution of a boundary value problem involving oblate spheroidal functions. In particular, this is the first time that ITD results for diffraction from the disc and hole in a plane geometries are validated using exact solutions computed at a caustic. In all cases examined, very good agreement is found. </para>

Zeroth Order Resonance Loop Antenna

A new type of low-profile omnidirectional antenna is proposed in this paper. The proposed antenna has the conceptual configuration of the horizontal magnetic loop current on perfect electric conductor plane, which has been realized by the zeroth-order resonator (ZOR) antenna using mushroom structure. The mushroom structure as a transmission line has negative, zero, and positive propagation constant depending on its operation frequency since mushroom structure is artificial composite right-left handed transmission line. Zeroth-order resonance, of which frequency is independent of physical length, is naturally presented. In particular, mushroom ZOR antenna generates a uniform vertical electric field against ground plane, so that it omnidirectionally radiates in a horizontal plane. Operation frequency, absolute gain, and gain variations for omnidirectional radiation of the designed prototype are 7.9 GHz, 2.6dBi, less than 1.5 dBi, respectively

Electromagnetostatic image theory for the PEMC sphere

The perfect electromagnetic conductor (PEMC) is a generalisation of both perfect electric-conductor (PEC) and perfect magnetic-conductor (PMC) media. Its definition, through differential-form formulation, corresponds to the simplest possible electromagnetic medium definable by a single parameter, the PEMC admittance. Its realisation for time-harmonic fields appears possible by a layer of bi-isotropic material on a PEC plane. As a basic problem, the extension of Kelvin&apos;s electrostatic image theory for the PEC sphere to that for the PEMC sphere is considered here. It is shown that, applying a suitable duality transformation, classical results for the PEC sphere can be applied to find the image solution which, for an electric point charge, involves both electric and magnetic point and line sources. The analytic result is checked by some known special cases.

Realization of the PEMC boundary

Perfect electromagnetic conductor (PEMC) is a nonreciprocal generalization of both the perfect electric conductor (PEC) and the perfect magnetic conductor (PMC). Because PEMC does not allow electromagnetic energy to enter, it can serve as boundary material. Possibilities for the realization of a PEMC boundary are studied in terms of a layer of certain nonreciprocal materials resting on a PEC plane. It is shown that the parameters of a bi-isotropic or a gyrotropically anisotropic medium can be chosen so that the interface of the layer acts as a PEMC boundary to normally incident waves. After a modification of medium parameters, the same is shown to be asymptotically valid for arbitrary plane waves. A structure for the realization of such a boundary is suggested.

Image theory for electromagnetic sources in chiral medium above the soft and hard boundary

The classical image theory valid for electromagnetic (EM) sources in an isotropic medium above a planar perfect electric conductor (PEC) or perfect magnetic conductor (PMC) surface was extended to involve the planar soft-and-hard surface (SHS) boundary that can be realized with tuned corrugations. The image principle is now generalized to EM sources in isotropic chiral medium above an SHS boundary. The problem is solved by two consecutive decompositions of the sources reducing the problem to four classical ones involving electric and magnetic sources above PEC and PMC boundaries; each involving an isotropic nonchiral medium and possessing a known image solution. One of the decompositions is based on the fact that the two eigenwaves of a chiral medium do not couple at a soft-and-hard surface; and, the other one, on the eigenpolarizations of the reflection dyadic.

EM wave simulation: An animated electromagnetic wave teaching package

AbstractThis paper describes EM Wave Simulation, a windows‐based animated electromagnetic wave simulation package, developed as a supplementary tool for teaching electromagnetic field theory at the undergraduate level. For the purpose of rapid display of electromagnetic wave images, the implemented algorithm assumes a structure sandwiched between two perfect electric conductor planes and employs a 2½‐dimensional finite‐difference time‐domain (FDTD) method on a staggered grid, which is suitable for simulating simplified electromagnetic wave propagation in indoor environments. Frequency‐domain spectral information can be extracted with the built‐in one‐ and two‐dimensional discrete Fourier transforms facilities. A user‐friendly mouse‐and‐menu‐driven interface allows user to set up simulations containing complex geometries in a straightforward fashion. Simulated results, in both time and frequency domains, can be displayed in real‐time on the computer screen, which makes the application ideal for use in interactive undergraduate teaching. Some sample simulations are discussed in the paper to illustrate its principal functionality. © 2002 Wiley Periodicals, Inc. Comput Appl Eng Educ 9: 208–219, 2001; Published online in Wiley InterScience (www.interscience.wiley.com.); DOI 10.1002/cae.10001

Asymptotic Green's function of a surface magnetic current element on a perfect electric conductor plane covered by a lossy dielectric substrate

Published analyses of radiation modeling for slot structures on dielectric substrate are empirical or numerical. This paper proposes exact analytical asymptotic expressions of the far-field Green's functions of a surface magnetic current element on a perfect electric conductor plane covered by a lossy dielectric substrate of finite thickness. From these expressions, the radiation pattern of both the space wave and surface wave far away from an arbitrary shaped-slot antenna structure can be calculated, provided the source distribution across the slot is known. The potentials used in the analysis are defined and their boundary conditions are expressed. The Helmholtz equation is solved in the Laplace domain and the solutions are transformed into the space domain using the inverse Hankel transform and steepest descent method. The influences of the substrate thickness and dielectric constant are analyzed using the calculated expressions. The model is validated by comparison with surface wave and space wave measurements and with numerical results obtained from a commercial electromagnetic simulator.