Guided wave concept in electromagnetic theory

Abstract

This paper discusses a few engineering applications of the guided wave concept to the solution of electromagnetic problem in waveguide regions. Such problems must be reformulated rigorously as network problems that are generalizations o£ the conventional network problems of lumped circuit theory. The network point of view is particularly apropos for the calculation of the electromagnetic field produced by prescribed current sources; it is likewise applicable in diffraction problems wherein the sources are induced, and hence initially unknown. As an illustration of the former case, known Sommerfeld type problems of the field of a dipole above dielectric structures are treated in network terms. In special cases these become the "ideal troposphere" or the "coated conductor" problem, whence the related question of "trapped" or "surface" waves is viewed in· a network light. As an example of a diffraction problem, the plane wave scattering by two displaced semi-infinite planes is solved in terms of a network formalism that is equivalent to a Fourier transform procedure employing Schwinger's application of the Wiener-Hopf technique.