Radiating Systems, Multipole Fields and Radiation — John David Jackson
Physics — E&M · right-triangle-waveguide-modes
Problem
A waveguide is constructed so that the cross section of the guide forms a right triangle with sides of length a, a, 2a, as shown. The medium inside has μr=ϵr=1.
(a) Assuming infinite conductivity for the walls, determine the possible modes of propagation and their cutoff frequencies.
(b) For the lowest modes of each type calculate the attenuation constant, assuming that the walls have large, but finite, conductivity. Compare the result with that for a square guide of side a made from the same material.