Abstract
A novel compact microstrip ultra-wideband (UWB) bandpass filter with three sharply notched bands and good selectivity is presented in this letter. Triple-notched bands filtering effects are achieved by adding open-circuited stubs and introducing asymmetric dual-line coupling structure to the feed lines, providing a high degree of adjusting freedom and not increasing the filter size. The frequencies of the notched bands and the upper stopband transmission zero can be independently controlled by adjusting the structural parameters of feed lines. Finally, a microstrip UWB filter with triple-notched bands is simulated and fabricated with good agreement.
Disclosure statement
No potential conflict of interest was reported by the authors.