Open AccessDesign of compact planar power divider with wideband bandpass response and high in‐band isolation
Author(s) -
Wang Xuedao,
Wang Jianpeng,
Zhu Lei,
Choi WaiWa,
Wu Wen
Publication year - 2021
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/mia2.12114
Subject(s) - passband , microstrip , band pass filter , power dividers and directional couplers , electric power transmission , wideband , resistor , electronic engineering , transmission line , impedance matching , electrical impedance , computer science , topology (electrical circuits) , engineering , electrical engineering , voltage
In this study, a compact planar power divider (PD) with wideband bandpass response is proposed based on a coupled three‐line filtering prototype. With two back‐to‐back microstrip feeding lines and a coplanar waveguide resonator located in the middle ground plane, the filtering structure is constructed. According to the synthesis approach, the proposed filtering structure can achieve an equal in‐band ripple response with three transmission poles and four out‐of‐band transmission zeros. In order to make the proposed PD inherit the designed filtering performance, one of the output lines in the filter network is modified to realize a 50 to 25 Ω impedance transformation in the passband first. Then, for good in‐band isolation and impedance matching at output ports, the modified output line is split into two separated lines by a slot so that a lumped resistor can be loaded at the ends of the two separated output lines. By properly setting the slot width and the resistance with guidance, high isolation level over an ultra‐wide passband is attained. For demonstration, three cases of the PDs with different bandwidths are designed on the basis of the corresponding filter designs. Finally, two bandpass PDs are fabricated and tested to verify the design concept.