Analysis of Regular Pentagonal Waveguide Using Conformal Mapping

The metallic regular pentagonal waveguide (RPWG) is investigated using the conformal mapping technique (CMT). A regular pentagonal cross-section is transformed into the simple circular one using conformal mapping (CM). The Galerkin method is applied to obtain the cutoff frequency from the wave equation in the transformed domain for the dominant TM mode. The internal E and H fields pattern for dominant TM mode of a regular pentagonal metallic waveguide is obtained using the CMT. The cutoff frequency is obtained for dominant TM mode of a RPWG is compared with the conventional 3D HFSS simulator. It is found that our theory can predict the cutoff frequency of RPWG with less than 0.5% error. Internal field patterns of the RPWG for the dominant TM mode are shown using the CMT. The dispersion diagram of RPWG is plotted using our theory. It is found that our theory has excellent agreement with the 3D EM simulator