A COMPACT DUAL-PASSBAND FILTER USING STEPPED-IMPEDANCE RESONATORS

摘要

In this letter, a new coupling configuration of the stepped-impedance resonator (SIR) has been presented to design dual-passband filters with the small circuit size. We design the filter with higher selectivity based on SIR direct-coupling, input, and output external quality factors. Through resonance characteristics of a SIR, the second resonant frequency can be tuned by adjusting structure parameters. The agreement between measured results and full-wave simulation prediction validates the feasible configuration of the proposed filters.