Open AccessBalanced dual‐band BPF with intrinsic common‐mode suppression on double‐layer substrate
Author(s) -
Wang Kai,
Zhu Lei,
Wong SaiWai,
Chen Dong,
Guo ZaiCheng
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.2015.0327
Subject(s) - band pass filter , resonator , multi band device , materials science , electrical impedance , optoelectronics , dual mode , excited state , passband , stub (electronics) , substrate (aquarium) , common mode signal , physics , electronic engineering , optics , electrical engineering , engineering , atomic physics , oceanography , geology , antenna (radio) , digital signal processing , analog signal
A balanced dual‐band bandpass filter (BPF) with enhanced common‐mode (CM) suppression is proposed. The dual‐band differential‐mode (DM) bandpass response is obtained using a double‐layer substrate. The stub‐loaded stepped‐impedance resonators are used both in the top and the bottom layers to constitute a dual‐band BPF with two controllable passbands. The slotline portion in the middle layer is excited under DM operation. Moreover, the even‐symmetrical field along the slotline is highly attenuated under CM excitation, thus achieving excellent CM suppression over the desired DM passbands. To verify the proposed concept, a balanced dual‐band BPF, operating at 1.9 and 2.8 GHz, is designed and fabricated, and the simulated and measured results are in good agreement.