利用時域有限差分法解微帶線之結構

Abstract

摘要 本論文使用有限差分時域法探討微帶線之散射參數，且使用PML-ABC 作為FDTD 之吸收邊界條件。論文中探討激發源發射位置置於邊界面若干格距，有別於激發源置於邊界面上，造成邊界面既為信號面亦為吸收邊界面，此種切換的麻煩。此外，亦証實在50 ohm 微帶線上，PML ABC 之吸收率較Mur ABC 來得好。論文模擬及實作出微帶線之其他結構。

Abstract In this thesis, the Finite-Difference Time-Domain (FD-TD) is employed to study the scattering parameters of microstrip structures, based on the use of Berenger's perfectly matched layer (PML) boundary condition. To begin with, a simple and efficient source excitation scheme for the FD-TD analysis of microstrip structures is developed. In this scheme, by moving the source plane several cells inside the near-end boundary, the interaction between the excitation and reflected waves are totally separated in time domain. In addition, the thesis verifies Berenger's PML ABC is more accurate than the Mur ABC for a 50ohm infinitely long microstrip line. The FD-TD method employing Berenger's PML is applied to analysis the coupled-line couplers, nonuniform coupled microstrips, and three-line microstrips. The simulated and measured S-parameters are shown and discussed in this thesis.