W頻段矩形波導管至基板整合波導轉換器與基板整合波導混成耦合雙工器之改進

Abstract

本論文前半部主要在討論如何設計轉換器將W-頻段的矩形波導管的能量導入一般PCB製成的基板整合波導中，得到出符合需求、穩定性高的轉換器；後半部則著重於將基板整合波導混成耦合雙工器改進並使用本篇論文所開發出來的轉換器進行量測。 本論文使用的板材皆為損耗較低的Rogers RT-Duroid 5880TM，其介電常數為2.2，論文中將討論板材厚度與品質因子(Q值)的關係，最後我們採用Q值較高的10mil厚板材做為實作與模擬的板材厚度，並以此厚度的板材設計本篇論文裡所有基板整合波導電路，而轉換器的結構大小也將以此基板厚度作為設計基準進行設計與開發。 在W-頻段中，所有的元件對機械尺寸都非常敏感，本論文研究了轉換器中對反射損耗具影響力的機械與PCB製程參數，並將機械結構予以改進，及比較其改進前後的結果。最後再配合開發完成的矩形波導管至基板整合波導轉換器組合設計出來的幾種電路進行量測，並討論其與模擬結果不同的原因。

In the first part of this thesis, we design and implement a W-band highly stabile and repeatable transition to guide the electromagnetic wave from rectangular waveguide to substrate integrated waveguide (SIW). The second part of the thesis describes the study of a W-band quadrature hybrid coupled diplexer in cooperated with the transition developed in the first part of this thesis. The substrate used in the circuits of this thesis is a low dielectric loss Rogers RT Duroid 5880TM substrate with a dielectric constant of 2.2. A study on the unloaded quality factor value (Q-value) of a SIW resonator with respect to the substrate thickness shows that a thicker substrate has a better Q-value. Therefore a 10 mil other than 5mil thick substrate is chosen to implement all of the transitions and circuits. The mechanical dimensions of a W-band circuit should be very accurate. In this thesis, we have studied the most critical mechanical dimensions and PCB processes on the performance of the proposed transition. The mechanical housing of the transition has been modified after several runs of the prototype circuits. The performances of the transition before and after the modification have been discussed. Finally, several circuits combined with this newly developed transition have been realized, measured, and discussed.