Design of Multi-Band Microstrip Bandpass Filter of Cross-Coupled Structure with Tunable Transmission Zeros

• Main Authors: Jyun-ShuChen, 陳俊樹
• Other Authors: Bing-Jing Li
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/17111185885160679164

碩士 === 國立成功大學 === 電機工程學系碩博士班 === 98 === A multi-band microstrip band-pass filter using cross-coupled structure is presented in this paper. We investigated two kinds of multi-band microstrip band-pass filter structures ,including a dual-band filter and a tri-band filter. For the dual-band filter, we implemented the novel dual-band filters based on coupled open loop resonator and uniform impedance ring resonator with cross-coupled structure. The tri-band band-pass filter was referred to a periodic step impedance resonator structure with ring resonator. By using the theory of tri-section step impedance resonator, we calculated the ratio of fundamental and spurious frequency by SIR for the design of dual-band filters, as well as the correct design ratio for the ring structure. The location of spurious response can be adjusted, which contributed to the tri-band characteristics of the band-pass filter. The measurements were in good agreement with the simulation for the design of dual-band and tri-band filters.