A wide-band bandpass filter using the properties of microstrip open-loop resonator with spurious response suppression

Abstract

A wide-band bandpass filter using the properties of microstrip open-loop resonator with spurious response suppression is proposed here. The resonator consists of four identical branches with attached to inner and outer corner of the square loop. The introduction of two tuning stubs widens the passband and sharpens the stopbands. The filter is designed 2.45 GHz and proposes 36% bandwidth with 0.38 dB insertion loss and return loss greater than 10 dB. It very useful for the wireless communications systems.