Ttl Method Applied To the Fin-Line Resonators

Abstract

This work makes use of the full wave method for the calculation of the resonance frequency of a rectangular resonator finline. Another important innovation is to use Fortran Powerstation for the calculation of the resonance frequency. The results are presented in graphs in three dimensions. The computational time for the execution of the programs is relatively small. A slot resonator in a unilateral fin line is the basic circuit element that is extensively used as a building block in the design of fin-line filters. It is also useful in other millimeter-wave circuits, such as oscillators and mixers. In the direct and concise TTL method, the Maxwell equations in Fourier transform domain, are firstly used to obtain the electromagnetic fields in terms of the transversal electromagnetic fields. By applying the boundary conditions, the fields in all dielectric regions are determined as functions of the electric fields in the resonant slot. An inhomogeneous equation system is obtained, in which the current densities in the conductor fins are related to the electric fields in the slot. By expanding these fields in terms of suitable basis functions and using the moment method and the Parseval's theorem, the current densities are eliminated, and a homogeneous equation system is obtained with two variables. The complex resonant frequency is obtained by setting the determinant of the system matrix equal to zero. The results for the unilateral fin line resonator are presented for different parameters including substrate thickness, permittivity, length and width of the slot resonator.