具寬截止帶之雙頻帶通濾波器之設計

Design of a dual-band bandpass filter with a wide rejection band

黃威翔(Wei-Shiang Huang)

指導教授 ： 鄭士康

國立臺灣大學/電機資訊學院/電信工程學研究所/碩士(2009年)

https://doi.org/10.6342/NTU.2009.00416

摘要

本論文提出兩種利用不同抑制方法，完成三個具有抑制倍頻響應之雙頻帶通濾波器。第一個三階雙頻濾波器乃利用步階阻抗共振器所完成的，透過巧妙安排兩個步階阻抗共振器之基頻和倍頻的關係，則可以不需再外加其它元件就可有效達成雙頻帶且具有寬的截止帶；而第二個雙頻濾波器則是引入具有殘段之指叉型電容以及四分之ㄧ波長開路殘段來產生零點，並將這些零點放置於倍頻產生之處以期能夠抑制倍頻並達到寬截止帶；最後一個雙頻濾波器亦是利用四分之ㄧ波長開路殘段所產生的零點來達成寬截止帶。本論文所提出之三個濾波器各有優劣，可視應用之範圍與規格來挑選較符合之濾波器，另外，吾人亦透過實驗數據來驗證濾波器設計理論分析之可行性。

關鍵字

寬截止帶 ； 雙頻 ； 濾波器

並列摘要

We use two methods to suppress the spurious frequency of three dual band bandpass filters in this thesis. The first 3rd dual band filter was composed of stepped impedance resonators. We can achieve dual band and a wide rejection band effectively by arranging the relationship between the base frequency and the spurious frequency skillfully. For the second filter, we introduce interdigital capacitance with stubs and open stubs to produce zeros, and try to locate these zeros in the location of the spurious frequency, therefore we also can achieve a wide rejection band. We also use open stubs to produce zeros and achieve a wide rejection band in the last filter design. The three filters have their pros and cons respectively. Users can choose the best one according to the range and specification of applications. Also, the experimental results show that our filter design is feasible.

並列關鍵字

wide rejection band ； dual band ； filter

參考文獻

[1] C. W. Tang and M. G. Chen, “Wide stopband parallel-coupled stacked SIRs bandpass filters with open-stub lines,” IEEE Microwave and Wireless Components Letters, Vol.16, pp.666-668, Dec.2006.

[2] C. F. Chen, T. Y. Huang and R. B. Wu, “Design of microstrip bandpass filters with multiorder spurious-mode suppression,” IEEE Transactions on Microwave Theory and Techniques, Vol.53, No.12, pp.3788-3793, Dec.2005.

[3] C. W. Tang and Y. K. Hsu, “Design of a Wide Stopband Microstrip Bandpass Filter With Asymmetric Resonators,” IEEE Microwave and Wireless Components Letters, Vol.18, No.2, pp.91-93, Feb.2008.

[4] C. W. Tang and H. H. Liang, “Parallel-Coupled Stacked SIRs Bandpass Filters With Open-Loop Resonators for Suppression of Spurious Responses,” IEEE Microwave and Wireless Components Letters, pp.1-3, 2005.

[5] Q. X. Chu and F. C. Chen, “A Compact Dual-Band Bandpass Filter Using Meandering Stepped Impedance Resonators,” IEEE Microwave and Wireless Components Letters, Vol.18, No.5, pp.320-322, May.2008.