Quasi-TEM rectangular waveguides with frequency selective surface walls: Part I - Electrical properties and geometrical characteristics
Apr 01, 2014
DOI: https://doi.org/10.1002/jnm.1954
Publisher: John Wiley & Sons, Ltd.
Electrical properties and geometrical characteristics of frequencyâ€selectiveâ€surfaceâ€loaded quasiâ€transverse electromagnetic (TEM) rectangular waveguides are investigated in detail. The properties of electrical field distributions over the cross section of waveguides at various periodical phase shift points are studied. The phenomena, in connection with artificial magnetic conductor (AMC), cavity resonance, and surface resonance, are discussed. A definition of bandwidth for AMC is proposed on the basis of the variation of average zâ€polarized electric fields along zâ€axis between two side dielectric surfaces. Standard deviation technique is used to describe the uniformity of electrical fields and cavity efficiency is defined to represent the percentage of useful cavity with uniform electrical fields. The dispersion relationship, bandwidths of AMC and single mode, and cavity efficiency for various types of AMC surfaces are examined and compared. The geometrical characteristics of quasiâ€TEM waveguides are studied in both theory and experiment. Design rules for highâ€quality quasiâ€TEM waveguides are proposed.