Based On The Straight-line Method Of Finite Conductivity With The Thickness Of The Microstrip Line Performance Analysis And Software Implementation

The Microstrip line is one of the most widely used microwave planar transmission lines in the monolithic microwave integrated circuit (MMIC) and hybrid microwave integrated circuit (HMIC), because of its advantages, such as small volume, light weight, low cost, high reliability, superior performance, application of the photo lithography process, and easily integrated with other passive and active microwave devices. For analyzing the characteristics of the microstrip transmission lines, the most traditional methods are to assume that the strip is infinite thin, and the metals are the perfect electric conductor. With the development of millimeter wave technology and microwave integrated circuit technology, the dimensions of monolithic microwave integrated circuits are decreasing while operating frequency is increasing. The cross-section dimensions of the microstrip line become similar to the wavelength. For the skin effect, considering conduction strips as infinitely thin perfect electric conductors will bring great errors. It is necessary to consider the effect of the finite strip thickness.In this thesis, based on the comprehensive comparison of some methods for analyzing the characteristics of microstrip lines with the finite strip thickness, such as the quasi-static method, the moment method, the spectral domain method, etc., and finally the method of lines has been chosen. The basic principles of the method of lines are introduced and applied to analyzing the characteristics of microstrip lines with the finite strip thickness. The relationship of electromagnetic field components on interfaces of the layers with the inhomogeneous media has been deduced and the homogeneous media has been considered as a special form of the inhomogeneous one. The system equations, which can be solved to get the results of the microstrip transmission characteristics, are obtained. Some improvements and problems with the solutions, which exist in the process of analysis, have also been discussed. Moreover, the accuracy and convergence behavior are discussed by comparing the results obtained by the method of lines with those gotten in the literatures, HFSS and experimental measurements. The effects of strip thickness and metal conductivity are summed up. Finally, the software is finished by developed with the Visual C++ 6.0. The software can analyze a variety of transmission line structures, and the software is easy to use, Full-featured, has fast calculation and higher accuracy. It can use to a separate analysis or to export the results in combination with other software.