Convergence study of cutoff frequencies of the finline structure for different types of trial functions by the transverse resonance method

The purpose of this work concerns the modeling of a microwave planar structure which is the "finline" structure. We have used a numerical method called the "transverse resonance method" using the formalism of mathematical operators applied to the electromagnetism. We have established a computer program permitting the calculation of the matrix elements necessary to determine the parameters characterizing the dispersion effect and therefore leading to the calculation of the values of the cutoff frequencies in the dispersive mode. We have obtained results up to a frequency of 50 GHz which are in agreement with those in international publications.