COMPUTER AIDED DESIGN OF STEPPED IMPEDANCE TRANSFORMERS REALIZED IN COAXIAL TRANSMISSION LINE

Abstract

This paper describes computer programs that have been developed to design quarter-wave and short-step impedance transformers. In the literature dealing with these transformers usually there are tables to make designing easier, but in these the fringing capacitances occurring at the steps between lines of different impedances are not taken into considera- tion. The computer programs can calculate these capacitances and compensate for their effects. For short-step impedance transformers they can design dielectric supports as well. These programs are able to design transformers up to ten sections in a structure where the outer conductor has constant diameter and the inner conductor is alternating. At the end of this publication the different matching structures are compared on some examples.