Filter Banks Using Series-switching Structure

• Main Authors: Tsai, Hsiu-Min, 蔡秀敏
• Other Authors: 張志揚
• Format: Others
• Language: zh-TW
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/38367551505114704752

碩士 === 國立交通大學 === 電信工程研究所 === 104 === The thesis studies a series-switching filter bank structure that solves the difficulty of fabrication of SPNT switch of the conventional parallel-switching filter bank as the channel number becomes large. At first, use J/K inverters equivalent coupled transmission lines to design a third-order Chebyshev short-ended hairpin comb filter. Next, to insert a PIN diode at the center of first and last resonators finishes the single electronically switchable filter design which can be switched on and off by reverse and forward biasing the PIN diodes. Finally, serially connecting three of the electronically switchable filters by transmission lines with appropriate lengths accomplishes the proposed three channel filter bank. The center frequencies of filter bank are 2.35 GHz, 2.425 GHz and 2.55 GHz that correspond to Band40, WIFI band and Band38 respectively. The circuit are fabricated using Rogers RO4003 substrate with thickness of 20 mil, dielectric constant of 3.55 and dielectric loss tangent of 0.0027, and measured by Agilent E8364B PNA Network Analyze.