A NOVEL NUMERICAL SYNTHETIC TECHNIQUE FOR DETERMINATION OF THE TMON DISPERSION-RELATION IN A COAXIAL CORRUGATED CYLINDRICAL WAVE-GUIDE

A novel, highly accurate numerical synthetic technique for determining the complete dispersive characteristics of electromagnetic modes in a spatially periodic structure is presented. The numerical method based on the coupling of the finite difference method in time domain with t he discrete fourier transform is applied to calculate the eigenfrequen cies and eigenfield distribution of a resonant cavity which is an appr opriately shorted periodic slow wave circuit of N periods at both ends . The analytical synthetic technique, which is based on the intrinsic characteristic of spatially periodic structure, is used to derive the complete dispersion relation using the numerically measured resonances . The method was successfully applied for the case of TNon modes in a coaxial corrugated waveguide and is applicable to slow wave structures of arbitrary geometry.