STUDY OF SCATTERING PARAMETERS OF WAVEGUIDE DEVICES USING COMSOL MULTYPHYSICS

Abstract

S-parameters refer to the scattering matrix. The concept was first popularized around the time that Kaneyuke Kurokawa of Bell Labs wrote his 1965 IEEE article Power Waves and the Scattering Matrix. It helped that during the 1960s, Hewlett Packard introduced the first microwave network analyzers. The scattering matrix is a mathematical construct that quantifies how RF energy propagates through a multi-port network. The S-matrix is what allows us to accurately describe the properties of incredibly complicated networks as simple "black boxes. One difficulty associated with transmission parameters is that in a practical high-frequency circuit it is extremely difficult to obtain the perfect opencircuit and short-circuit conditions required to make good measurements. The Sparameter method circumvents the open/short difficulties by always connecting both ports to transmission lines with stable, well-defined impedances. To the extent that such a test setup better represents the actual working conditions of your circuit, the S-parameter method generates a more accurate model. These are the reasons why this thesis topic is chosen. In this thesis paper, an idea about what is S-parameters, it’s classification and usefulness is described elaborately. Then here the mathematical and network based analysis is done which helps to know about S-parameters more accurately. Here Sparameters are expressed with mathematical equations. Examples are being done by the help of the software named FEMLAB. FEMLAB is a powerful, interactive environment for modeling and solving scientific and engineering problems based on partial differential equations. It has helped to know the detailed status of waves in different types of waveguides. These detailed statuses are being described at the end of this thesis.