Novel low-pass filter for broad-band spurious suppression

Novel microstrip-type low-pass filters are proposed to effectively suppress spurious response in stop-band. The proposed low-pass filter employs an open stub microstrip inserted by thin or thick film resistors in the place of a conventional open stub microstrip. The proposed low-pass filters was shown to suppress the spurious response by more than 20/spl sim/40 dB compared with conventional microstrip low-pass filters.