運用雙頻帶通濾波器設計雙工器與耦合線結構之180°混成器

Design of Diplexer With Dual-Band Bandpass Filters and Synthesis of 180° Hybrid With Coupled-Line Structure

蔡政儒(CHENG-JU TSAI)

指導教授 ： 湯敬文

國立中正大學/工學院/電機工程學系/碩士(2016年)

摘要

本論文分為兩個部分，第一部分為運用雙頻帶通濾波器設計雙工器，首先利用步階阻抗T型諧振腔產生雙模態，再利用耦合係數法控制輸入/出埠的饋入位置和調整T型諧振腔的間距設計雙頻濾波器，最後運用有諧波抑制效果的結合器合併兩組不同操作頻率的雙頻濾波器形成雙通帶雙工器。
第二部分介紹耦合線結構之180°混成器，運用耦合線結構達到縮小180°混成器之電路面積，並使用奇偶模對稱理論來分析其電路，在端埠1和端埠4加入開路殘段來抑制諧波，耦合線結構之180°混成器相較傳統型180°混成器有較小面積跟較好的頻帶外抑制，上述兩個電路設計，使用電磁模擬軟體IE3D進行模擬輔助，以及實際製作電路進行量測。經由電磁模擬與量測的結果比較，兩者具有良好的一致性。

關鍵字

雙工器 ； 諧波抑制 ； 180°混成器 ； 縮小化

並列摘要

The thesis contains two parts. The first part will introduce a diplexer with dual-band bandpass filters. Dual mode response can be provided by T shape step impedance resonator. The use of tapped input/output and the adjustment of gap between two T shape resonators can achieve dual-band bandpass filters. Last, Dual-band diplexer can be formed by combining two different operating frequency dual-band filters with harmonic suppression combiner.
The second part will introduce an 180° hybrid with coupled-line structure. Coupling structure can reduce 180° hybrid’s area. Analytical equations of the circuit are derived from using the even-odd mode. In order to improve harmonic suppression, we add open stubs at port1 and port4. The 180° hybrid with coupled-line structure’s area is smaller and the harmonic suppression is better than traditional 180° hybrid structure. These two circuits are simulated with electromagnetic simulator software IE3D, and the prototype of these two circuits are fabricated and measured. Comparing the simulated results with the experimental data, we can see that the measured results can match well with the EM simulation.

並列關鍵字

diplexer ； harmonic suppression ； 180° hybrid ； miniaturization

參考文獻

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