Ultra-wideband bandpass filters with a controllable and highly selective notch-band

✍ Scribed by Liang Zhou; Shao-bin Liu; Xiang-kun Kong; Hai-feng Zhang; Ya-nan Guo

• Publisher: John Wiley and Sons
• Year: 2011
• Tongue: English
• Weight: 202 KB
• Volume: 53
• Category: Article
• ISSN: 0895-2477
• DOI: 10.1002/mop.26376

✦ Synopsis

Abstract

In this letter, a novel band‐notched ultra‐wideband (UWB) bandpass filter (BPF) is investigated. A structure of complementary two turns spiral resonator (CSR2) is proposed to improve notch performance of the UWB BPF. The single CSR2 unit cell has a size of 0.08λ~g~ × 0.08λ~g~(what is λ~g~) at stop‐band center frequency (5.7 GHz). With respect to the resonance nature of the miniaturization and high Q value, a compact UWB BPF with multiple CSR2s is designed. The proposed filter demonstrates band‐stop‐filter‐like response with high frequency selectivity and controllable bandwidth at rejection band. We assess the filtering behavior of structures from two aspects: the return loss and the group delay. The measured notched band frequency is range from 5.05 to 5.85 GHz(|S11|<−10dB). The maximum attenuation is more than 28 dB at the central frequency of 5.37 GHz. The measured and simulated results are well‐complied with each other. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:2920–2922, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26376