在射頻前端電路中，濾波器扮演著非常重要的角色，直接影響了整體通訊系統的效能和雜訊，因此，研究並設計高效能的雙頻濾波器為本論文所探討的重點。本論文以開路雙行態共振器(open-circuit dual-behavior resonators, OC-DBRs)為基礎，設計微小化的單頻及雙頻的帶通濾波器，其研究主要分為兩個部分，第一部分為PCB微波濾波器的應用，分別利用兩種不同簡化型的濾波器合成理論設計方法，針對2.4 GHz與5.2 GHz個別的頻帶設計出對稱型與非對稱型濾波器，設計過程中引入三段式步階阻抗共振器來縮小濾波器的面積，將上述分別設計的2.4-GHz與5.2-GHz單頻帶通濾波器結合，最後在Duroid5880，介電係數為2.2的板材上實現雙頻帶通濾波器，第二部分則是利用微帶線的架構來實現TSMC 0.18 μm CMOS製程所設計的24/60-GHz的雙頻帶通濾波器毫米波射頻晶片，引入開路雙行態共振器的概念，每個開路型雙行態共振器皆可獨立地調整，任意的設計出所需的通帶和傳輸零點的位置，但開路端的電容與不連續的電容與電感所造成的影響使得傳輸零點的位置移到更低的頻率，因此需要針對頻率稍作修正。24/60-GHz雙頻帶通濾波器之量測結果顯示: 在23-25 GHz通帶為S21 > -3.7 dB，S11 < -15 dB ，在57-64 GHz通帶為S21 > -2.8 dB，S11 < -10 dB; 在34/40 GHz低頻傳輸零點為 -22/-32 dB與87/88 GHz的高頻傳輸零點為 -46/-48 dB。

This thesis presents the research on dual-band bandpass filters for 2.4-/5.2-GHz WLAN application and 24-/60-GHz vehicular radar system and WPAN applications. The first part presents some designs based on the stepped impedance resonators (SIRs) theory and the dual-behavior resonator (DBR) concept. The SIRs applied to the dual-band filter design can control second passband by adjusting the impedance ratio and electric lengths of SIRs. The SIRs are also applied to the structure of DBRs. DBRs are composed of the parallel combination of several different open-ended stubs structures. The second part presents the design and implementation of a 24/60-GHz millimeter-wave dual-band on-chip bandpass filter using a 0.18-µm standard CMOS process. The concept of quarter-wave-length stepped impedance resonator (λ/4 SIR) is utilized to realize stopband characteristics at desired frequencies and size reduction. The structure of the open-circuited dual-behavior resonators (OC-DBRs) produces one passband with two transmission zeros on either side. The simulated and measured results are in good agreement. The fabricated CMOS filter chip size is 1.03 0.59 mm2. The measured insertion loss of the passband at 24 and 60 GHz is about 3.6 and 2.8 dB, respectively, and the return loss is better than 15 and 10 dB, respectively. The rejections in the stopbands are all lower than -20 dB.

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