SELF-COMPLEMENTARY EM FIELDS IN SELF-COMPLEMENTARY STRUCTURES

摘要

This paper analyzes electromagnetic fields in complementary and self-complementary structures. As is well known, Maxwell's equations exhibit a symmetry between the electric and magnetic fields. Self-complementary field solutions (when these exist) on self-complementary structures have particular properties of constant impedance (resistance) associated with pure traveling wave fields. The contribution of this paper is that it rigorously treats the electromagnetic field in a waveguide self-complementary structure, and it shows a self-complementary field solution as a pure traveling TEM wave. A new waveguide structure is devised that illustrates circumstances when a self-complementary field solution fails to exist in a self-complementary structure. A computer model was developed to analyze a family of waveguide structures that differ only in an aspect ratio parameter, an aspect ratio of 1.0 corresponding to the self-complementary case. At low frequencies (one mode propagating), field solutions for the input TEM mode exhibit discontinuous behaviour as the aspect ratio approaches 1.0 from above and below. No self-complementary field solution exists for the precisely self-complementary waveguide structure, and the input impedances for aspect ratios greater and less than 1.0 do not, in any sense, approach the value predicted for a self-complementary solution.