集總-分散式耦合線帶通濾波器

Parallel-Coupled Bandpass Filters Based on Lumped-Distributed Coupled-Line Sections

楊錫明(Hsi-Ming Yang)

指導教授 ： 陳俊雄

國立臺灣大學/電機資訊學院/電信工程學研究所/碩士(2005年)

https://doi.org/10.6342/NTU.2005.00662

摘要

此論文提出「集總-分散式耦合線帶通濾波器」，以達成縮小化、高止帶衰減率、寄生通帶抑制的目標。
論文中的「集總-分散式耦合線帶通濾波器」，乃藉由在傳統耦合線段的末端接上集總式電容或電感性負載，以縮短耦合線段的長度。此外，由於引入了電容性或電感性交互耦合(cross-coupling)的機制，在通帶的兩側可置入傳輸零點(transmission zero)。而傳輸零點的位置，可簡單地藉由改變產生交互耦合的電容或電感的大小去調整。我們也建立了「傳統耦合線段」與「分散-集總式耦合線段」間的簡易等效模型，並將之應用於「縮小化耦合線帶通濾波器」的設計與研究當中。
另外針對濾波器的倍頻響應，本論文也提出了改善的方法，並且不需額外增加其他元件而增加設計上的困難度。

關鍵字

帶通濾波器 ； 耦合線 ； 交互耦合

並列摘要

In this study, parallel-coupled bandpass filters based on lumped-distributed coupled-line sections have been proposed to possess the merits of compact size, good selectivity, and good stopband rejection.
Novel parallel-coupled bandpass filters are proposed, by using additional lumped capacitors or inductors to reduce the length of coupled-line sections. In addition, by introducing the capacitive or inductive cross-coupling effect, transmission zeros can be achieved to improve the filter selectivity. The locations of transmission zeros may be simply adjusted by varying the cross-coupling capacitance or inductance. Simple equivalent-circuit models and design formulas are also established, from which the proposed parallel-coupled bandpass filters based on lumped-distributed coupled-line sections may be design and investigated.
Furthermore, the approach to suppress the spurious response is also discussed so as to enhance the stopband characteristics.

並列關鍵字

bandpass filters ； coupled-line ； cross-coupling

參考文獻

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