Spurious suppression of a microstrip bandpass filter using three types of rectangular PBG loops.
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.
Weng
Min-Hung
MH
Yuan
Ru-Yung
RY
Huang
Tsung-Hui
TH
Chen
Han-Jan
HJ
Chen
Wu-Nan
WN
Houng
Mau-Phon
MP