Open AccessSharp roll‐off lowpass filter using interdigital DGS slot
Author(s) -
Liu Shuai,
Xu Jun,
Xu Zhitao
Publication year - 2015
Publication title -
electronics letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.375
H-Index - 146
eISSN - 1350-911X
pISSN - 0013-5194
DOI - 10.1049/el.2015.0721
Subject(s) - stopband , low pass filter , transition band , cutoff frequency , ground plane , filter (signal processing) , materials science , acoustics , physics , band pass filter , prototype filter , optoelectronics , computer science , optics , engineering , electrical engineering , telecommunications , antenna (radio)
A novel lowpass filter (LPF) with a sharp roll‐off and a wide stopband is presented. The proposed LPF is based on a dual‐plane structure with an interdigital shape defected ground structure (DGS). The DGS exhibits a sharp roll‐off and three transmission zeros. By tuning the length of the fingers, the resonant frequency can be easily changed. Based on the proposed DGS, a LPF has been designed, fabricated and measured. The transition band is from 3.11 ( f c ) to 3.23 GHz with −3.02 and −22.5 dB, respectively. The stopband with rejection better than 25 dB can be extended to 3.4 f c .