Open AccessA compact sept‐band bandpass filter utilising a single multi‐mode resonator
Author(s) -
Bi Xiaojun,
Wang Luhua,
Ma Qiang,
Hu Baoquan,
Xu Qinfen
Publication year - 2019
Publication title -
iet microwaves, antennas and propagation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.555
H-Index - 69
eISSN - 1751-8733
pISSN - 1751-8725
DOI - 10.1049/iet-map.2018.6082
Subject(s) - band pass filter , resonator , insertion loss , gsm , wi fi , wireless , filter (signal processing) , electronic engineering , materials science , passband , optoelectronics , physics , acoustics , topology (electrical circuits) , computer science , telecommunications , engineering , electrical engineering , wireless network
This study proposes a compact sept‐band bandpass filter (BPF) with controllable centre frequencies and bandwidths. To achieve compact size and low insertion loss, the filter deploys a single multi‐mode resonator and abandons conventional source–resonator coupling structure to reduce the order of coupling sections. The fabricated BPF demonstrates seven passbands located at 1.0, 1.6, 2.3, 2.8, 3.5, 4.2, and 5 GHz, which are targeted for global system for mobile communications (GSM), wireless local area network, WIFI, and 4G/5G communication. Within the seven passbands, the minimum insertion losses are 0.9, 1.5, 0.5, 1.2, 0.9, 1.9, and 1.6 dB, respectively. The overall size of the fabricated filter is 0.1 λ g × 0.21 λ g . This work provides a new approach to obtain the most passbands of BPF while achieving less insertion‐loss and enhanced selectivity simultaneously.