- 學位論文
使用六角型諧振腔之三頻帶通濾波器與高隔離度濾波功率分配器之設計
Design of the Tri-passband Bandpass Filter With Hexagonal Grounded Resonators and Filtering Power Divider With High Isolation
摘要
本論文分為兩個部分，第一部分介紹三頻帶通濾波器之設計，該電路分別是由兩個六角形接地諧振器和一個方形挖槽以及兩個六角形開路殘段來達到三個頻帶的帶通濾波器。驗證理想等效電路與電路佈局的關係，再藉由切奇、偶模分析的方式，驗證零點的位置。 第二部分介紹具高隔離度濾波功率分配器，在此功率分配器中，首先使用步階阻抗耦合線以實現抑制諧波的效果；在輸出端加入L-type開路殘段，分割步階阻抗耦合線產生的模態，並增強頻帶內的匹配；再串接一段短路對稱耦合線使得通帶外產生傳輸零點，加強抑制諧波的效果；並且在輸入端加入L-type短路殘段加強頻帶內的匹配；最後，藉由串接電阻和電容，使得通帶內具有高隔離度之特性。
並列摘要
The thesis includes two parts. The first part will introduce a novel compact tri-passband bandpass filter is proposed and developed. The proposed filter consists of two hexagonal grounded resonators, one rectangular slot, and two hexagonal patches. The resonators, slot and patches can control three passbands with 3, 5.5, and 9.4 GHz for central frequency, respectively. The equivalent circuit and design procedures of the tri-passband bandpass filter are provided as well. The second part will introduce a compact microstrip power divider with wide stopband and high isolation, which use step impedance coupled line to create a transmission zero；use short coupled line to create a extra transmission zero；add a L-type open stub at output port to improve the return loss of passband and also create a extra transmission zero；final add a L-type short stub at input port to impro the in-band’s return loss. And series resistance and capacitance for better isolation performance in passband.