Premium
Ultra‐wide stopband low‐pass filter using symmetrical cascaded modified hairpin resonators
Author(s) -
Karimi Gholamreza,
Hamedani Farnaz Khamin,
Siahkamari Hesam
Publication year - 2014
Publication title -
international journal of rf and microwave computer‐aided engineering
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.335
H-Index - 39
eISSN - 1099-047X
pISSN - 1096-4290
DOI - 10.1002/mmce.20763
Subject(s) - stopband , passband , return loss , insertion loss , transition band , elliptic filter , resonator , materials science , cutoff frequency , low pass filter , microwave , filter (signal processing) , band stop filter , band pass filter , center frequency , dissipation factor , prototype filter , m derived filter , optics , physics , optoelectronics , dielectric , telecommunications , electrical engineering , engineering , antenna (radio) , quantum mechanics
An elliptical function low‐pass filter (LPF) with ultra wide stopband and sharp cutoff frequency is proposed. This filter is composed of symmetrical cascaded modified hairpin resonators and U‐shaped resonators. The transition band is from 1 to 1.21 GHz with −3 and −20 dB, respectively. For this filter, the return loss is better than 17 dB in 80% of passband width, where the insertion loss is less than 0.3 dB. The band‐stop rejection is greater than 20 dB from 1.21 to 26.35 GHz and 40 dB from 1.35 to 12.5 GHz. To validate the design and analysis, the proposed LPF has been designed and fabricated on a 20 mil thick RO4003 substrate with a relative dielectric constant 3.38 and loss tangent of 0.0021. The filter is evaluated by experiment and simulation with a good agreement. © 2013 Wiley Periodicals, Inc. Int J RF and Microwave CAE 24:314–321, 2014.