A novel broad-band Chebyshev-response rat-race ring coupler

Author

Chang, Chi-Yang ; Yang, Chu-Chen

Author_Institution

Dept. of Commun. Eng., Nat. Chiao Tung Univ., Hsinchu, Taiwan

Volume

47

Issue

4

fYear

1999

fDate

4/1/1999 12:00:00 AM

Firstpage

455

Lastpage

462

Abstract

A novel broad-band rat-race ring coupler with a unit element at each port and an ideal phase inverter at one of the ring arms is proposed and analyzed. Design equations based on Chebyshev equiripple functions are derived. The design curves of equal or unequal power division are also presented. Theoretical data show that the bandwidth of unequal power division with a specific return-loss value increases as the power division ratio increases or decreases from unity. For a 180° hybrid with equal power division (3 dB) and 15-dB return loss, the proposed rat-race ring may have a bandwidth of 4:1. Three circuits of this novel rat-race ring are realized using finite-ground-plane coplanar waveguide. The measured results match very well with the theory

Keywords

Chebyshev approximation; coplanar waveguide components; power dividers; waveguide couplers; 15 dB; Chebyshev equiripple functions; broad-band Chebyshev-response; design equations; equal power division; finite-ground-plane coplanar waveguide; ideal phase inverter; power division ratio; rat-race ring coupler; return loss; specific return-loss value; unequal power division; unit element; Arm; Bandwidth; Chebyshev approximation; Coplanar waveguides; Coupling circuits; Equations; Inverters; Microwave circuits; Narrowband; Phase shifters;

fLanguage

English

Journal_Title

Microwave Theory and Techniques, IEEE Transactions on

Publisher

ieee

ISSN

0018-9480

Type

jour

DOI

10.1109/22.754879

Filename

754879