paper 150205065215

Published: 2015-07-09

A Compact Tunable Dual-band Bandpass Filter Using Varactor-loaded Step-impedance Resonators

Chang Chen,

Chang Chen

The 38th Research Institute of China Electronic Technology Group Corporation, China

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Mingkang Li,

Mingkang Li

Chinese Academy of Sciences, University of Science and Technology of China, China

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Bin Liu,

Bin Liu

Chinese Academy of Sciences, University of Science and Technology of China, China

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Xiang Zhang,

Xiang Zhang

Chinese Academy of Sciences, University of Science and Technology of China, China

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Lingyun Zhou

Chinese Academy of Sciences, University of Science and Technology of China, China

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Proceedings of 2015 Photonics & Electromagnetics Research Symposium, Prague, July 6 - 9，Page(s)2642-2645

Abstract

This paper presents a novel design of a compact tunable dual-band bandpass filter (BPF) using varactor-loaded step-impedance resonators(SIRs). The proposed filter structure offers the possibility of two tunable passbands. Compared to uniform impedance resonator (UIR), the SIR has more excellent performance such as compact size, and adjustable harmonic resonant frequency etc. The harmonic resonant frequency of SIR is determined by the length of SIR and the ratio of the two characteristic impedances. By choosing proper ratio of the two characteristic impedances, the length of SIR can be shorter than UIR with the same resonance frequency. So the proposed filter using varactor-loaded SIRs can be compact. Both theory and experiment are provided to validate the proposed filter. A prototype tunable dual-band filter is fabricated and measured. From the experimental results, the first passband center frequency tunable range is from 0.7 GHz to 1.2 GHz and the second passband center frequency tunable range is from 1.4 GHz to 2.15 GHz.

Citation

Chang Chen, Mingkang Li, Bin Liu, Xiang Zhang, and Lingyun Zhou, "A Compact Tunable Dual-band Bandpass Filter Using Varactor-loaded Step-impedance Resonators," Proceedings of 2015 Photonics & Electromagnetics Research Symposium, Prague, July 6 - 9，Page(s)2642-2645

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