Using The Generalized Transmission Line Equation Modeling Microstrip Circuit

The dissertation is supported by the research foundation project of the City University of Hong Kong, is a part of "High-performance Computing for Applied Electromagnetic Problems by Using On-Surface Measured Equations of Invariance method", the aim is to testify the existence of a novel transmission differential equations from numerical validation, by modeling microstrip circuit structure, and exacting the applicable circuit parameters in wide frequency range, radiation efficient can represent the local energy radiation and emission at sampling point.In the first part, the Moment of Methods and software IE3D based on moment of methods are analyzed, Then we derive the novel generalized transmission line equations from arithmetic operators theory and two-port network H parameter circuit matrix.In numerical validation, we first use conventional transmission line equations to model microstrip structure, then we use Generalized transmission line equations to model microstrip structure and compare both circuit parameters ,. When using the exacted circuit parameters to restore voltage and current, considering lack of two boundary conditions, we get another two equations by extrapolating current distribution equations at the excitation and loading ports.In this way, we still can't restore current and voltage distribution well, commonly, we use Liu equations to solve the problem, but another problem occurs, that is the exacted circuit parameters have some subtle changes, when we directly use H parameter matrix to model microstrip line to get circuit parameters and compare with those extracted by Generalized transmission line equations.The goodness of using H parameter matrix modeling is that when restoring current and voltage distribution, don't need extrapolation equations, and Generalized transmission line equations can model microstrip gap structure, surpass the limits of the conventional transmission line equations. Due to our Generalized line equations is based on software IE3D, the precision of software IE3d will take a critical effect on our exacted circuit parameters, so the effect of mesh division is analyzed,Finally, we take the conclusion as follows 1. , circuit parameters exacted by generalized transmission line equations is applicable.2. The existence of is still unknown from the numerical validation and definite physical comprehensions need more discussion.3. When frequency is too high, due to conventional transmission line equation is difficult to model microstrip structure, so the conventional transmission line equations have some improvement maybe.