On the Miniaturized Narrow Bandpass filter for the PHS Communication System

• Main Authors: Chih-Wei Li, 李志偉
• Other Authors: 陳凰美
• Format: Others
• Language: zh-TW
• Published: 2004
• Online Access: http://ndltd.ncl.edu.tw/handle/92089034200532685588

碩士 === 國立臺灣科技大學 === 電子工程系 === 92 === Abstract In this thesis, we use the quasi-elliptic filter synthesis method which produces a pair of zeros at finite frequencies to design highly selective bandpass filters. In addition, we derive the design equation for the miniaturized hairpin resonators. Then we take advantage of the cross coupling property of appropriately arranged resonators to produce a pair of finite frequency zeros. The coupling coefficients for resonators and the quality factors for resonators are then discussed with respect to the specifications. Then, two possible signal-feeding structures are discussed as well. Finally, we implement the miniaturized narrow bandpass filter with the bandwidth of 30MHz at 1.9GHz, and investigate the method to decrease the influence on the center frequency by the harmonic frequencies. In addition, we use the full-wave EM simulator(IE3D) in simulation. By implementing and simulating the full-wave EM simulator, we show that the theoretical and experimental performance are consistent.