INTEGRAL-EQUATION SCALAR GREEN-FUNCTION FORMULATION FOR COMPUTATION OF CUTOFF WAVE-NUMBERS AND MODAL FIELDS IN WAVE-GUIDES

A scalar formulation for cutoff wavenumber and modal field calculation s is presented. Integral equations are used with a scalar Green's func tion for a two dimensional rectangular resonator for both TE and TM mo des. These are transformed into matrix equations by the Galerkin metho d. The electric TE held is calculated from the scalar potential and is written in the form of a contour integral. The advantage of the scala r formulation is the simple form of the matrix eigenvalue equations wh ich are used in the moment method solution, and the economy in CPU tim e in the determination of TE cutoff wavenumbers.