COMPUTATION OF CUTOFF WAVE-NUMBERS FOR PARTIALLY FILLED WAVE-GUIDES OF ARBITRARY CROSS-SECTION USING SURFACE INTEGRAL FORMULATIONS AND THE METHOD OF MOMENTS
Sf. Shu et al., COMPUTATION OF CUTOFF WAVE-NUMBERS FOR PARTIALLY FILLED WAVE-GUIDES OF ARBITRARY CROSS-SECTION USING SURFACE INTEGRAL FORMULATIONS AND THE METHOD OF MOMENTS, IEEE transactions on microwave theory and techniques, 41(6-7), 1993, pp. 1111-1118
A procedure for determining the cutoff wavenumbers of partially dielec
tric filled waveguides of arbitrary cross section is presented. A nume
rical approach based on surface integral formulations and the method o
f moments is used to obtain a matrix equation. Muller's method is then
applied to find the wavenumbers that make the matrix determinant vani
sh. These are the cutoff wavenumbers. On the conducting walls of the w
aveguide, perfect electric conductor, perfect magnetic conductor, and
imperfect conductor surfaces are considered. The transverse electric a
nd magnetic cases are treated separately. The impedance boundary condi
tion and the symmetry of the waveguide cross section are used to reduc
e the matrix size in the method of moments. Spurious modes have not be
en observed using this method. To validate the accuracy of this method
, results for circular, partially filled rectangular, and two walled c
orrugated rectangular waveguides are compared to analytical results. E
xamples such as T-septate rectangular, coaxial, and dielectric-loaded
double-ridged waveguide are also considered. Accurate prediction on th
e cutoff wavenumbers is achieved.