A UHF Compact Complex Impedance-transforming Balun with High Isolation

Author(s): Kittipong Nithiporndecha, Chatrpol Pakasiri*

Journal Name: Recent Advances in Electrical & Electronic Engineering
Formerly Recent Patents on Electrical & Electronic Engineering

Volume 13 , Issue 8 , 2020

Become EABM
Become Reviewer
Call for Editor

Graphical Abstract:


Background: A compact complex impedance-transforming balun for UHF frequencies, which is based on a coupled-line structure that matched all ports and provided high output port isolation, was designed in this paper.

Methods: A lumped component transformation was used to minimize circuit size. The implemented circuit operated at 433 MHz with the reflection coefficients less than -16 dB at all ports, 0.22 dB amplitude balance and 180° phase balance at the output ports. The signal coupling between the output ports was -16.8 dB. The circuit size is small at 0.032λ.

Results: Complex impedance-transforming baluns were designed to operate at 433 MHz. The source impedance at port 1 was set at Zs = 12 - j12Ω and the load impedances at port 2 and 3 were set at ZL = 80 + j30Ω.

Conclusion: A compact complex impedance-transforming balun at UHF frequency, with all ports matched and high isolations, was designed and illustrated in this paper.

Keywords: Balun, complex impedance, lumped-component, UHF, SiGe BiCMOS technology, two pot circuit.

Rights & PermissionsPrintExport Cite as

Article Details

Year: 2020
Published on: 03 December, 2020
Page: [1135 - 1144]
Pages: 10
DOI: 10.2174/2352096513666200212103557
Price: $25

Article Metrics

PDF: 6