IEICE Electronics Express
Online ISSN : 1349-2543
ISSN-L : 1349-2543
A novel design approach to the miniaturization of dual-band branch-line coupler
Milad MirzaeeMehdi Nosrati
Author information

2011 Volume 8 Issue 24 Pages 2029-2034


In this paper, a novel design approach for significant size reduction of a class of dual-band branch-line coupler (BLC) by use of a transmission line model loaded with a folded-T-type stepped-impedance-stub (FTTSIS) is proposed. At the first step, by loading FTTSIS at the middle of each branch instead of stepped-impedance-stub (SIS) in the conventional branch-line coupler, a compact dual-band BLC with same performance that is about 65% of the conventional one is achieved. Then by mirroring the FTTSISs of 35Ω lines inside the inner space of the proposed structure, miniaturized dual-band BLC that is only 30% of the conventional dual-band BLC operating at same WLAN frequencies is obtained. The proposed structure is then fabricated and measured. The measurement results show good agreement with the theoretical ones.

Content from these authors
© 2011 by The Institute of Electronics, Information and Communication Engineers
Previous article Next article