寬度具週期變化微帶線之波導特性分析

Abstract

本論文主要探討具週期變化之微帶線，其結構包含兩種:(1)微帶線之導線寬度在傳播方向上具週期變化﹔(2)基板之介質材料於傳波方向上具週期變化。本論文利用有效介電常數方法計算週期變化傳輸線結構之色散特徵解，配合簡單的圖解法與波模耦合理論，除了能夠確實掌握該結構中通，禁帶分布的物理機制外，並且能夠提供工程設計法則，以作為電路設計之參考依據。

In this thesis, the single mode approximation is employed to investigate the guiding characteristics of the microstrip line with periodic variation. The structure under consideration contains two types: one is the width-modulated microstrip structure and the other is that of substrate-modulated one. The numerical results are displayed in the form of the Brillouin diagram with the phase and attenuation constants both. On the other hand, the scattering of guided-wave by the finite size periodic microstrip has also been carried out in this thesis. In addition, the passband and stopband behavior is verified by the measured data. Thus, the numerical results provide not only the clear physical picture for the phenomena involved in the periodic structure but also the design criterion for practical considerations.