Premium
Dual‐band branch‐line coupler with shorted stepped‐impedance stubs arranged in a Π‐shaped topology
Author(s) -
Seko Murilo Hiroaki,
Correra Fatima Salete
Publication year - 2019
Publication title -
microwave and optical technology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.304
H-Index - 76
eISSN - 1098-2760
pISSN - 0895-2477
DOI - 10.1002/mop.31745
Subject(s) - multi band device , microstrip , transmission line , hybrid coupler , topology (electrical circuits) , electrical impedance , electric power transmission , line (geometry) , rat race coupler , electronic engineering , engineering , characteristic impedance , electrical engineering , power dividers and directional couplers , mathematics , geometry , antenna (radio)
This article presents a transmission‐line‐based 3‐dB dual‐band branch‐line coupler. The coupler is easily realizable for ratios between the upper and lower operating frequencies ranging from 1.270 to 2.628. This means that it can be designed for two operation frequencies that are closer to each other in comparison with existing simple circuit topologies based on transmission lines, when considering a compact design. The complete set of equations for all possible responses of this dual‐band 90° hybrid coupler is derived. To evaluate its practical feasibility, the proposed circuit is analyzed with respect to the characteristic impedances of its transmission lines. A step‐by‐step procedure is presented to help the circuit designer deal with the use of the equations and all their degrees of freedom. For experimental validation, a microstrip dual‐band branch‐line coupler has been designed for operation at 3.835 and 5.285 GHz. A good agreement is observed between simulated and measured results.