The 2D Nonpenetrable Parallel Plate Waveguide

This chapter deals with high frequency electromagnetic wave propagation in guiding environments. After an introductory overview of issues and physical interpretations pertaining to this broad subject area, detailed attention is given to the simplest canonical, thoroughly familiar, test environment: a (time-harmonic) line-source-excited two-dimensional (2D) infinite waveguide with perfectly electrical conducting (PEC) plane-parallel boundaries. After formulating the Green's function (GF) problem within the framework of Maxwell equations, alternative field representations are presented and interpreted in physical terms, highlighting two complementary phenomenologies: progressing (ray-type) and oscillatory (mode-type), culminating in the self-consistent hybrid ray-mode scheme which is usually not included in conventional treatments at this level. This provides the analytical background for two educational MATLAB packages which explore the dynamics of ray fields, mode fields, and the ray-mode interplay: RAYMODE package and HYBRID package. Finally, the chapter focuses on eigenvalue extraction from propagation characteristics and tilted beam excitation.