Perfect Electric Conductor Cylinder Research Articles

DIRECTIVE EM RADIATION OF A LINE SOURCE IN THE PRESENCE OF A COATED PEMC CIRCULAR CYLINDER

Electromagnetic scattering of a line source from a perfect electromagnetic conductor (PEMC) circular cylinder coated with double positive (DPS) material or double negative (DNG) material is investigated theoretically. The response of the coated PEMC circular cylinder is observed and it is noted that how the results obtained for this configuration differ from those of a coated perfect electric conductor (PEC) circular cylinder. It is assumed that both the PEMC cylinder and the coating layer are infinite along the cylinder axis. The comparison of directivity of coated PEMC cylinder and coated PEC cylinder is presented.

Reshaping the perfect electrical conductor cylinder arbitrarily

A general method is proposed to design a cylindrical cloak, concentrator and superscatterer with an arbitrary cross section. The method is demonstrated by the design of a perfect electrical conductor (PEC) reshaper which is able to reshape a PEC cylinder arbitrarily by combining the concept of cloak, concentrator and superscatterer together. Numerical simulations are performed to demonstrate its properties.

Superscatterer: Enhancement of scattering with complementary media

Based on the concept of complementary media, we propose a novel design which can enhance the electromagnetic wave scattering cross section of an object so that it looks like a scatterer bigger than the scale of the device. Such a "superscatterer" is realized by coating a negative refractive material shell on a perfect electrical conductor cylinder. The scattering field is analytically obtained by Mie scattering theory, and confirmed by full-wave simulations numerically. Such a device can be regarded as a cylindrical concave mirror for all angles.

Electromagnetic Scattering from Parallel Perfect Electromagnetic Conductor Cylinders of Circular Cross-Sections Using an Iterative Procedure

Electromagnetic scattering from an array of parallel perfect electromagnetic conductor (PEMC) circular cylinders, illuminated by a TM z plane wave, is investigated using an iterative procedure. Both the near and far fields, due to any number of interactions between the cylinders, may be determined. The technique applies the boundary conditions on the surface of each cylinder in an iterative procedure in order to solve for the field expansion coefficients. Numerical verifications are presented to prove the validity of the derived results and the numerical code, by comparison with the published literature for perfect electric conductor cylinders.

Achieving transparency and maximizing scattering with metamaterial-coated conducting cylinders

In this work, the electromagnetic interaction of plane waves with infinitely long metamaterial-coated conducting cylinders is considered. Different from "conjugate" pairing of double-positive (DPS) and double-negative (DNG) or epsilon-negative (ENG) and mu-negative (MNG) concentric cylinders, achieving transparency and maximizing scattering are separately achieved by covering perfect electric conductor (PEC) cylinders with simple (i.e., homogeneous, isotropic, and linear) metamaterial coatings. The appropriate constitutive parameters of such metamaterials are investigated for Transverse Magnetic (TM) and in particular for Transverse Electric (TE) polarizations. For TE polarization it is found out that the metamaterial-coating permittivity has to be in the 0<epsilonc<epsilon0 interval to achieve transparency, and in the -epsilon0<epsilonc<0 interval to achieve scattering maximization. However, unlike the "conjugate" pairing of DPS-DNG or ENG-MNG cases, when the transparency for metamaterial-coated PEC cylinders are considered, the analytically found relation between epsilonc and the ratio of core-coating radii, gamma, should be modified in a sense that scattering from the PEC core is canceled by the coating. Furthermore, replacing epsilon by mu (and vice versa) does not lead to the same conclusions for TM polarization unless the PEC cylinder is replaced by a perfect magnetic conductor (PMC) cylinder. On the other hand, scattering maximization can also be achieved in the TM polarization case when coating permeability muc<0, whereas transparency requires large |muc| for this polarization. Numerical results in the form of normalized monostatic and bistatic echo widths, which demonstrate the transparency and scattering maximization phenomena, are given and possible application areas are discussed.

TRANSIENT MULTIPATH ANALYSIS OF CIRCULAR CYLINDERS ABOVE SINUSOIDAL SURFACES USING A RAY TRACING METHOD

The deterministic problem of transient, short-pulse scattering from a perfect electric conductor cylinder above flat and sinusoidal surfaces is undertaken. Previous work for the ultra-wide band analysis of both TE (vertical) and TM (horizontal) polarizations are utilized to solve this scattering problem. The possible paths traveled by the reflected waves are calculated and the multiple reflections are identified by using timing analysis. Transient multipath effects for a cylinder above a sinusoidal surface are contrasted with those for a cylinder above a flat surface.

Finite elements and absorbing boundary conditions for scattering problems on a parallel distributed memory computer

An efficient finite element method is presented to compute time harmonic microwave field in three dimensional configurations. Nodal-based finite elements have been coupled with an algorithm boundary condition to solve open boundary problems. Modeling real devices is made possible using parallel computation. This paper describes first the time harmonic formulation with the absorbing boundary condition and the sequential code. A new algorithm is then proposed to implement this formulation on a cluster of workstations (10 DEC ALPHA 300X). Analysis of efficiency is performed using simple problems. The electromagnetic scattering of a plane wave by a perfect electric conductor cylinder is finally given as example.