On the Independence of the Excitation of Complex Modes in Isotropic Structures

Author

Islam, Rubaiyat ; Eleftheriades, George V.

Author_Institution

Edward S. Rogers Sr. Dept. of Electr. & Comput. Eng., Univ. of Toronto, Toronto, ON, Canada

Volume

58

Issue

5

fYear

2010

fDate

5/1/2010 12:00:00 AM

Firstpage

1567

Lastpage

1578

Abstract

We investigate the independence of the excitation of complex modes in lossless and isotropic structures. We clarify some of the ideas in literature regarding the excitation of complex mode pairs. In particular, we show in this work that it is practically possible to independently control the excitation amplitude of an individual mode in a pair of conjugate complex modes. Theoretical clarification of the claim that such modes in a complex pair must be excited with equal amplitudes, as suggested by some authors, is also provided. The eigenmodes of a coupler comprising a regular forward-wave and a metamaterial backward-wave or negative-refractive-index transmission-line (NRI-TL) provides a representative platform to investigate our assertions which are verified using a commercial microwave circuit simulator.

Keywords

eigenvalues and eigenfunctions; metamaterials; waveguide theory; NRI-TL; complex mode pairs; conjugate complex modes; eigenmodes; excitation amplitude; isotropic structures; lossless structures; metamaterial backward-wave; microwave circuit simulator; negative-refractive-index transmission-line; regular forward-wave; Attenuation; Circuit simulation; Coupling circuits; Dielectrics; Iron; Loaded waveguides; Metamaterials; Microstrip; Microwave circuits; Plasma waves; Slabs; Transmission lines; Backward waves; complex modes; coupled-mode theory; metamaterials;

fLanguage

English

Journal_Title

Antennas and Propagation, IEEE Transactions on

Publisher

ieee

ISSN

0018-926X

Type

jour

DOI

10.1109/TAP.2010.2044341

Filename

5422691