Cross-Coupled Bandpass Filter Design Using Miniaturized Hairpin Resonators

摘要

In this paper, the miniaturized hairpin resonator has been thoroughly studied. Two equations for the odd and even modes resonance, which could be used to control the size and resonant frequencies of the resonator, are derived. A four-pole cross-coupled bandpass filter is designed by using these resonators. To improve the stopband rejection of the crosscoupled filter, the asymmetric feed structure is proposed. The locations of the transmission zeros introduced by the feed structure are derived according to the field patterns.