volume | PIER Journals

Abstract

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 λ_g x 0.079 λ_g where λ_g is the guided wave length. A BPF at the center frequency of f₀=1.9 GHz with stopband extended up to 7.8 GHz (=4f₀) is developed showing good agreement between simulation and experimental results.

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Mr. Johanny Alberto Escobar-Pelaez

Dr. Jose Luis Olvera Cervantes

Dr. Alonso Corona-Chavez

Dr. Humberto Lobato-Morales