Scattering From an Impedance Object at the Edge of a Perfectly Conducting Wedge

Abstract

Abstract-In this study, scattering from impedance bodies positioned at the edge of a perfectly electrically conducting wedge is investigated. In the treatment of the problem, eigenfunction expansion in terms of spherical vector wave functions is employed. A complete dyadic Green's function for the spherical impedance boss at the edge is developed. It is observed that the scattering is highly enhanced by the edge guided waves. Additionally, using T-matrix method, the solution is extended to the general case of irregularly shaped scatterers. The T-matrix solution is verified by applying it to the case of a spherical scatterer and results are compared with the dyadic Green's function solution.Index Terms-Dyadic Green's function, electromagnetic scattering, spherical vector wave functions, T-matrix, wedge scattering.

Analysis of edge waves due to a point source in the presence of a PEC wedge

“…The dyadic Green's function of the wedge and a spherical boss, WB Γ , is derived in [1] where the DGF is expanded in terms of spherical vector wave functions. This solution is valid almost everywhere and gives accurate results in the paraxial region.…”

“…Since the field should be regular at the origin, spherical Bessel functions denoted by superscript (1) are 978-1-4673-5225-3/14/$31.00 ©2014 IEEE As mentioned in [1][2] in the paraxial region scattered field is highly enhanced due to the edge guided waves and the dominant mode is 1, 0 m n = =…”

“…The canonical problem of scattering from impedance objects at the edge of perfectly conducting wedge is of interest in developing propagation models, radar cross section (RCS) calculations. In [1]we have presented a dyadic Green's function (DGF) solution for the spherical impedance scatterer at the edge is presented. In this work we investigate the dyadic Green's function in the paraxial region in order to determine the edge guided waves and their interaction with the scatterer on the edge.…”

Nano‐antenna synthesis for end‐fire and pencil‐beam far‐field radiation patterns using vector spherical wave functions

“…Another useful transformation is based on vector spherical wave functions (VSWF). This transformation is used when dealing with spherical boundaries and structures [23–31]. These vector functions are solutions of the Helmholtz equation.…”

“…Furthermore, they form an orthogonal set of base functions which makes them suitable choices for the expansion of EM waves to VSWFs [23]. There have been some researches on VSWFs for EM applications including calculating resonances of spherical structures, scattering, expansion of specific EM waves like plane‐waves or Gaussian beams and also dyadic Green's functions, antenna design, and so on [24–31]. Numerical optimisation methods are also widely used for antenna design purposes [12–15, 32–35].…”