A dual-mode uniplanar bandpass filter using an inset-coupling structure
novel dual-mode uniplanor square slot-loop resonator, using air inset-coupling mechanism with capacitive gaps is proposed. The mode splitting of the uniplanar resonator is described with respect to the perturbation size. A dual-mode uniplanor filter using such a resonator is designed and fabricated with 5% bandwidth at the center frequencey of 2.97 GHz for demonstration. The measured filter performance is presented. (C) 2004 Wiley Periodicals, Inc.