具阻抗轉換功能之耦合線耦合器

Coupled-Line Coupler with Impedance Transforming Characteristic

王文萍(Wen-Ping Wang)

指導教授 ： 張志揚

國立交通大學/電機學院/電信工程系所/碩士(2018年)

摘要

本論文利用四分之波長阻抗轉換傳輸線理論和耦合線耦合器理論為基礎，設計出寬頻具阻抗轉換特性之耦合線耦合器。本論文之耦合線耦合器是利用微帶線及增強耦合結構之耦合線所組成之平面電路，故在電路的實作上是容易實現的。
為了證實本論文所提出之四分之波長耦合線耦合器具寬頻阻抗轉換之特性，本論文實作兩個增強耦合結構之耦合線耦合器，分別為三截式耦合線耦合器具阻抗轉換耦合器與兩截耦合線耦合器串接四分之波長阻抗轉換耦合線之耦合器，使用板材為介電常數3.55的Rogers RO4003，板材厚度為 20 mil，操作中心頻率為 1.5GHz，輸入阻抗50歐姆以及輸出阻抗20歐姆；另一方面，由於有一端的阻抗為20歐姆，故在量測時須克服輸出阻抗與夾具間不同而產生的反射、相移問題。

關鍵字

阻抗轉換 ； 耦合線 ； 耦合器 ； 傳輸線 ； 被動電路

並列摘要

In this thesis, coupled-line coupler with impedance transforming characteristics is proposed using quarter-wavelength transformer and coupled-line coupler. It is a planar circuit consisted of microstrip lines and coupled line with enhanced coupling structures, which makes it simple to manufacture and reliable.
In order to generalize the concept with broadband impedance transforming characteristics, two coupled-line couplers with different constructure are designed and measured. The proposed coupled-line couplers, with center frequency 1.5GHz,input impedance 50 Ohm and output impedance 20 Ohm, are manufactured on a Rogers RO4003 substrate with dielectric constant of 3.55 and thickness of 20 mil. On the other hand, this thesis also emphasizes on overcoming the problem of measuring the circuit with input and fixture that cause the reflection and phase shift.

並列關鍵字

Impedance Transforming ； coupled-line ； coupler ； transmission line ； passive circuit

參考文獻

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