A knowledge of the fields in any waveguide is necessary in order to calculate its power flow, its attenuation and its impedance. The purpose of this chapter is to summarise some approximate closed form relationships for the fields in this type of waveguide and present some calculations based on the finite element method (FEM) procedure. The TE family of solutions is obtained by calculating H_z of the related planar problem region with top and bottom magnetic walls and forming the other components of the field by using Maxwell's equations. The TM family of solutions is obtained by solving the dual planar circuit with top and bottom electric walls. Comparison between the closed form and FEM procedures suggests that the closed form representation is adequate for engineering purposes. Some results on the standing wave solutions of the dominant and higher order modes of this sort of waveguide based on a magnetic field integral equation (MFIE) are also included. The power flow and attenuation are separately summarised.

Inspec keywords: magnetic field integral equations; ridge waveguides; finite element analysis; electromagnetic wave propagation; Maxwell equations

Other keywords: Maxwell's equations; double ridge waveguide; attenuation calculation; magnetic walls; planar problem region; waveguide fields; power flow; dual planar circuit; impedance calculation; finite element method; magnetic field integral equation; propagation

Subjects: Waveguides and microwave transmission lines