A Novel Rat-Race Coupler With Tunable Power Dividing Ratio, Ideal Port Isolation, and Return Loss Performance

Author

Cheng, K.M. ; Sung Yeung

Author_Institution

Dept. of Electron. Eng., Chinese Univ. of Hong Kong, Shatin, China

Volume

61

Issue

1

fYear

2013

fDate

Jan. 2013

Firstpage

55

Lastpage

60

Abstract

This paper presents, for the first time, a novel rat-race coupler design with tunable power dividing ratio. Wide tuning ratio is accomplished by the use of two tuning diodes and a single control voltage. Ideal port isolation and return loss characteristics, evaluated at the center frequency of operation, are proven for all dividing ratios. The structure is simple to construct and involves 50-ohm lines only. For verification, the simulated and measured results of a 1-GHz rat-race coupler implemented on microstrip are shown.

Keywords

UHF couplers; control voltage; frequency 1 GHz; microstrip; port isolation; power dividing ratio; rat-race coupler design; resistance 50 ohm; return loss characteristics; return loss performance; tuning diodes; tuning ratio; Couplers; Insertion loss; Loss measurement; Tuning; Voltage control; Voltage measurement; Planar circuits; rat-race coupler; tuning diodes; variable power dividing ratio;

fLanguage

English

Journal_Title

Microwave Theory and Techniques, IEEE Transactions on

Publisher

ieee

ISSN

0018-9480

Type

jour

DOI

10.1109/TMTT.2012.2228219

Filename

6389734