- 學位論文
具寬截止頻帶或寬頻帶之微波帶通濾波器設計
Design of A Microwave Bandpass Filter with A Wide Stopband or Passband
摘要
本論文提出一種具有抑止混附波，並改善截止帶特性之帶通濾波器設計。此濾波器架構是由傳統微小化髮夾式諧振腔加入步階式阻抗諧振腔，以及波浪狀耦合線結構所組成。 本論文之內容主要可分為電路設計與成品製作兩部分。在電路設計部分，首先決定濾波器之規格，再根據濾波器的基本理論求出所需之參數。在模擬軟體部分，乃利用Agilent公司的ADS設計軟體計算出外部品質因數，耦合係數及調整諧振腔之間的最佳距離。最後將此改良式濾波器分別設計並實現在RC4003C基板、FR4基板與WIN 0.15 μm pHEMT積體電路製程上。對RC4003C基板及FR4基板，其中心頻率為2.48GHz，對pHEMT製程，則為13.5GHz。 此濾波器設計之優點為，除具有相當寬之截止頻帶或通帶，對混附波有相當好之抑止效果，並具有相當小之電路尺寸。在成品的製作方面，實際量測與模擬的結果十分吻合。 此外，由於上述被動式濾波器會因電路中的電感、高頻共振器等，產生較大的寄生電阻，造成插入損耗變大。為了使插入損耗減少，本論文亦同時設計一Ku-band主動式濾波器來與高插入損耗的被動式濾波器進行比較。
並列摘要
This thesis presents a design of a bandpass filter with the suppression of spurious modes to improve stopband characteristics. To suppress the spurious modes, the configuration of this proposed bandpass filter adopted the structures of miniaturized hairpin resonator filter, stepped impedance resonators and wiggly-lines. Both the circuit design and implementation of the proposed bandpass filter were discussed in this study. First of all, we determine specifications of the bandpass filters. And then according to the basic design theory, the structure of filter is obtained with the parameters of the bandpass filters. For simulation, external quality factor, real coupling coefficient and optimum distance of the adjacent designed resonators was computed using Agilent’s ADS design software. Finally, the proposed bandpass filter were fabricated on RO4003C and FR4 substrates with center frequency of 2.48GHz, and by WIN 0.15 μm pHEMT Process with center frequency of 13.5GHz. In this design, advantages of the proposed bandpass filter are not only a wide stopband or passband, but also a good effect for suppression of spurious resonances and a compact size of the bandpass filter. For implementation of the proposed bandpass filter, the measured responses have close agreement with the simulation responses. Moreover, inductors and resonators of passive filters produce bigger spurious resistant resulting in a large insertion loss. In order to reduce this insertion loss, we also design a Ku-band active filter to compare with high insertion loss passive filters in this thesis.