Compact bandpass filter based on novel hairpin resonator with self-contained triple transmission zeros

• Main Authors: Wang, Yun Xiu, Zhu, Lei, Zhang, Songbai
• Other Authors: School of Electrical and Electronic Engineering
• Format: Article
• Language: English
• Published: 2014
• Subjects: DRNTU::Engineering::Electrical and electronic engineering
• Online Access: https://hdl.handle.net/10356/98623; http://hdl.handle.net/10220/18434; http://www.jpier.org/PIERL/pier.php?paper=13080906
• Institution: Nanyang Technological University

A compact coupled-line hairpin resonator is proposed and analyzed for designing a novel bandpass filter (BPF) in this letter. Compared with conventional stepped-impedance and stub-loaded resonator, the proposed resonator can produce three transmission zeros, which can be applied to achieve a wide and highly-attenuated upper stopband. To validate this attractive feature, a microstrip BPF is designed and fabricated with the center frequency at 2.4 GHz and a fractional bandwidth of 6%. Measured frequencies responses show a wider upper stopband up to 6.9 GHz (2.9f0) with insertion loss higher than 20 dB.