title: Spurious suppression of a microstrip bandpass filter using three types of rectangular PBG loops.
abstract: A novel microstrip bandpass filter with three types of rectangular, photonic bandgap (PBG) loops on a middle layer was designed and demonstrated using a full-wave electromagnetic (EM) simulator, with the predicted results verified by experiment. This investigation presents the configurations of conventional parallel-coupled 2 GHz filters with and without a PBG. The middle-layer of PBG loops adds an extra stopband-rejection mode to filter stopband; and it provides attenuation in excess of 25 dB at the second, third, and fourth harmonics, thus demonstrating that superior stopband characteristics at high frequency can be obtained using the proposed PBG loops in microwave filters.
authors.forename: Min-Hung
authors.initials: MH
authors.lastname: Weng
authors.forename: Ru-Yung
authors.initials: RY
authors.lastname: Yuan
authors.forename: Tsung-Hui
authors.initials: TH
authors.lastname: Huang
authors.forename: Han-Jan
authors.initials: HJ
authors.lastname: Chen
authors.forename: Wu-Nan
authors.initials: WN
authors.lastname: Chen
authors.forename: Mau-Phon
authors.initials: MP
authors.lastname: Houng