%0 Journal Article
%T A Bandpass Filter with Compact Size and Extended Stopband Using Closed-Loop Transmission-Lines and Short-Circuited Stubs
%A Johanny Alberto Escobar-Pelaez
%A Jose Luis Olvera Cervantes
%A Alonso Corona-Chavez
%A Humberto Lobato-Morales
%J PIER     Letters
%D 2012
%I EMW Publishing
%R 10.2528/PIERL12090309
%X A novel 3-pole bandpass filter (BPF) based on microstrip loaded ring resonators (LRRs) is proposed. Each resonator is composed by a closed-loop transmission line and a short-circuited stub. By properly adjusting the impedance and the electrical length of each resonator, the proposed circuit may be made compact (over 93.7% smaller than a conventional ring resonator) and its stopband may be extended simultaneously. Each resonator exhibits an area of 0.0727 ¦Ë x 0.079 ¦Ë where ¦Ë is the guided wave length. A BPF at the center frequency of =1.9 GHz with stopband extended up to 7.8 GHz (=4) is developed showing good agreement between simulation and experimental results.
%U http://www.jpier.org/pierl/pier.php?paper=12090309