Estimation of the electrodynamics parameters of the multilayer strip-slot transition based on the approximation of its equivalent circuit by the chebyshev filter of the first kind

The basic structural element of volume-modular microwave devices is a multilayer strip-slot transition, which provides electromagnetic coupling between its layers in a wide frequency range. The mathematical model of the multilayer strip-slot transition is known. It is based on the use of circuit analogies of its design elements. However, in the papers related to the study of its equivalent circuit only the amplitude-frequency dependences are reflected without analyzing other electrodynamics parameters, such as: phase-frequency characteristics and dependences of the input impedance on frequency. The purpose of this paper is to estimate the electrodynamics parameters of the multilayer strip-slot transition based on its equivalent circuit, approximated by the Chebyshev filter of the first kind and to conduct a comparative analysis of the results of its circuit and electrodynamics simulations. At the same time, the following simulation results are compared: 1) amplitude-phase characteristics of the functions of the reflection coefficient and transmission coefficient; 2) change in input impedance in the frequency range. As a result of the study it has been established that the equivalent circuit of the multilayer strip-slot transition can be approximated by the Chebyshev filter of the first kind. It allows to determine the necessary characteristic impedances of strip and slot resonators by given return/insertion losses in the pass band and their cutoff frequencies, while reflecting all electrodynamics characteristics correctly.