Design of tri‐band bandpass filter using symmetrical open stub loaded step impedance resonator. Issue 19 (1st September 2018)

• Record Type: Journal Article
• Authors: AbdulRehman, M.; Khalid, S.
• Is Part Of: Electronics letters. Volume 54:Issue 19(2018)
• Page Start: 1126
• Page End: 1128
• Publication Date: 2018-09-01
• Subjects: band‐pass filters -- band‐stop filters -- resonator filters -- UHF filters -- microwave filters -- UHF resonators -- microwave resonators; tri‐band bandpass filter design -- symmetrical open stub loaded step impedance resonator -- tri‐loaded open‐circuited stubs -- short‐circuited stub -- symmetrical SLSIR -- band rejection -- finite frequency transmission zeros -- passband edges -- substrate RT/Duroid 5880 -- design topology -- frequency 0.9 GHz -- frequency 2.4 GHz -- frequency 5.5 GHz; Electronics -- Periodicals; 621.381
• DOI: 10.1049/el.2018.5240
• Languages: English
• ISSNs: 0013-5194

Abstract

Abstract : A tri‐band bandpass filter design by using conventional stub loaded step impedance resonator (SLSIR) is presented. The proposed SLSIR consists of three tri‐loaded open‐circuited stubs parallel attached to a short and open‐circuited stub. A tri‐band bandpass filter is designed using two proposed symmetrical SLSIR's separated by a short‐circuited stub. In this configuration, the filter produces three bands of frequencies at 0.9, 2.4 and 5.5 GHz, respectively. It is shown that the resonating frequencies can be independently controlled by loaded stubs. For better out of band rejection and increased selectivity, four finite frequency transmission zeros around three passband edges are achieved. The obtained fractional bandwidths are 23, 10 and 17% centred at 0.9, 2.4 and 5.5 GHz, respectively. The proposed design topology is fabricated on a substrate RT/Duroid 5880. The simulated and measured results show good accordance. The fabricated prototype has a compact size of ( 0.13 × 0.16 ) λ g at 0.9 GHz.