Electromagnetic Simulation of New Tunable Guide Polarizers with Diaphragms and Pins

Abstract

In this article we present the results of electromagnetic simulation, development and optimization of a guide polarizer with a diaphragm and pins. An original mathematical model was obtained using the wave matrix approach for a guide polarizer with one diaphragm and two pairs of pins. The discontinuity elements were modeled as inductive or capacitive conductivities for two kinds of linear perpendicular polarizations of the electromagnetic waves. The theoretical model is based on wave scattering and transfer matrices. The total matrix of a polarizer was developed using wave matrices of transmission of separate elements of a polarizer’s structure. Using elements of the general S-parameters the electromagnetic characteristics of a considered polarizer were obtained. In order to test the performance of a suggested mathematical model, it was simulated in a software based on the finite elements method in the frequency domain. The presented design of a polarizer is adjustable due to possibility of mechanical tuning of the heights of applied pins. Considered guide polarizer with one diaphragm and two pairs of pins provides a reflection coefficient of less than 0.36 and a transmission coefficient of more than 0.93 for both linear perpendicularly polarized modes. Therefore, a new theoretical technique was developed in the research for fast electromagnetic simulation of wave matrix elements of a guide polarizers with diaphragms and pins. Developed simulation approach can also be widely used for the development of new tunable guide filters, polarizers, rotators and other microwave components with diaphragms and pins.