A Novel Bandpass Filter Using Asymmetric Open Stub-Loaded SIRs

Abstract:

A novel microstrip bandpass filter using stepped impedance resonators (SIRs) with asymmetric open stub-loaded is proposed in this paper. The filter uses asymmetric open stubs as capacitive loads, resulting in higher-order spurious frequencies suppression and wider upper stopband. Compared with the traditional filter based on stepped impedance resonators at the same design frequency of 2.4 GHz, the proposed filter can significantly reduce the circuit size of 45 %. By changing the geometric dimensions of the asymmetric open stub-loaded SIRs, which can achieve single-band bandpass filter at the centre frequency of 3.5 GHz and dual-band bandpass filter at the centre frequency of 2.4/3.5 GHz.

• Periodical: Applied Mechanics and Materials (Volumes 198-199)
• Pages: 1720-1725
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.198-199.1720
• Online since: September 2012
• Authors: Guo Gao Liu, Li Tian
• Keywords: Asymmetric Open Stub-Loaded, Bandpass Filter (BPF), Compact Size, Harmonics Suppression, Stepped Impedance Resonators (SIRs)

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