PROCEDIMENTO DE PROJETO PARA TRANSFORMADORES DE IMPEDÂNCIAS DE FAIXA LARGA UTILIZANDO LINHAS DE TRANSMISSÃO PARA CIRCUITOS DE RADIOFREQÜÊNCIA

Abstract

This paper shows a procedure for broadbandimpedance transformers design using transmission lines.These devices are widely used in several circuits ofcommunication equipments of radiofrequency andmicrowaves areas. Quarter-wave transformers with manysections are used and the quantity of structures dependson the bandwidth specified in the project. It is shown theequations and the analytical development for the totalreflection coefficient and characteristic impedance foreach section of transformer, based in the binomialtransformer and the theory of multiple reflections. Theinfluence of standing wave ratio coefficient is shown in thequantity of sections used by transformer to attendspecified bandwidth. The results obtained are presentedthrough simulations validating the model presented.Index Terms ⎯ Quarter-wave transmission linetransformer, reflection coefficient, standing wave ratio,multiple reflections.