Dual-Wideband Filtering Power Divider Based On Coupled Stepped-Impedance Resonators

• Published in: IEEE microwave and wireless components letters 2018-10, Vol.28 (10), p.873-875
• Main Authors: Wang, Xuedao, Wang, Jianpeng, Choi, Wai-Wa, Yang, Li, Wu, Wen
• Format: Article
• Language: English
• Subjects: Broadband; Couplings; Dual band; dual-wideband; Filtering power divider (FPD); Filtration; Impedance; Passband; Power dividers; Prototypes; Resonant frequency; Resonators; Selectivity; stepped-impedance resonator (SIR)
• ISSN: 1531-1309; 2771-957X; 1558-1764; 2771-9588
• DOI: 10.1109/LMWC.2018.2861578

A new approach to design dual-wideband filtering power divider (FPD) with high selectivity and wide stopband is presented. The proposed FPD is mainly composed of two pairs of tapped-line fed coupled stepped-impedance resonators and an isolation resistor. With this specific coupling structure, multiple transmission zeros are successfully generated, thus leading to a sharp skirt selectivity and a wide stopband. For demonstration, a prototype dual-wideband FPD operating at 2.43 and 5.06 GHz with size of 0.67 \lambda _{g} \times 0.68\lambda _{g} is designed, fabricated, and tested. The 3-dB fractional bandwidths are measured as 38.3% and 18.8%. Results indicate that the proposed FPD exhibits not only high selectivity with a 16-dB out-of-band rejection from 5.77 to 9.43 GHz but also a 19.8-dB port-to-port isolation within the whole operation band.