Title :
A compact enhanced-bandwidth hybrid ring using an artificial lumped-element left-handed transmission-line section
Author :
Okabe, Hiroshi ; Caloz, Christophe ; Itoh, Tatsuo
Author_Institution :
Commun. Devices Res. Dept., Hitachi Ltd., Tokyo, Japan
fDate :
3/1/2004 12:00:00 AM
Abstract :
A new type of compact enhanced-bandwidth hybrid ring using an artificial lumped-element left-handed (LH) transmission-line (TL) section is proposed. The replacement of the 270° branch of the conventional hybrid ring by a -90° LH-TL branch results in both size reduction and bandwidth enhancement. The working principle of the LH TL used in the hybrid ring is explained and the performances of the component are demonstrated by measurement results. The proposed hybrid exhibits 67% size reduction compared to the conventional one, and shows a 58% and 49% bandwidth enhancements at 2 GHz in the 180°-out-of-phase and in-phase operations, respectively.
Keywords :
directional couplers; equivalent circuits; lumped parameter networks; power dividers; transmission line theory; artificial lumped-element transmission-line section; bandwidth enhancement; compact enhanced-bandwidth hybrid ring; component performances; equivalent circuit model; left-handed transmission-line section; power divider; propagation constants; rat race; size reduction; Bandwidth; Coplanar waveguides; Equivalent circuits; MMICs; Microwave circuits; Microwave integrated circuits; Optical materials; Propagation constant; Transmission line theory; Transmission lines;
Journal_Title :
Microwave Theory and Techniques, IEEE Transactions on
DOI :
10.1109/TMTT.2004.823541
