[KSCI] Korea Science Citation Index Service

http://dx.doi.org/10.5515/JKIEES.2008.8.4.144

Tunable Combline Bandpass Filter Using Cross-Coupled Stepped-Impedance Resonators with Enhanced Characteristics

Kim, Yoon-Hong (Dept. of Electronic Engineering, Sogang University)
Cho, Young-Ho (Dept. of Electronic Engineering, Sogang University)
Yun, Sang-Won (Dept. of Electronic Engineering, Sogang University)

Publication Information

Journal of electromagnetic engineering and science / v.8, no.4, 2008 , pp. 144-147 More about this Journal

Abstract

This paper proposes a tunable combline bandpass filter with high selectivity, constant bandwidth, and good stopband performances. A filter with these characteristics is obtained by applying cross-coupling to the conventional combline bandpass filter using stepped-impedance resonators(SIRs). For high selectivity and constant bandwidth, cross-coupling is utilized and the SIR configuration is used for enhanced stopband performances. The proposed combline tunable bandpass filter with 5% of fractional bandwidth at 1.6 GHz was fabricated and tested. The measured results showed 11.6% tunability with constant bandwidth, high selectivity and enhanced stopband characteristics.

Keywords

Combline Filters; Stepped-Impedance Resonator; Cross-Coupling; Microstrip Filters; Transmission Zeros; Tunable Filters;

Citations & Related Records

Reference

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