Title :
Asymmetric coupled line directional coupler loaded with shunt inductors for directivity enhancement
Author :
Park, Je-Ho ; Lee, Youngjoo
Author_Institution :
Dept. of Electr. & Electron. Eng., Yonsei Univ., Seoul, South Korea
Abstract :
A directivity enhancement technique of shunt-inductive loading is demonstrated for asymmetric coupled line backward-wave directional couplers. Through rigorous normal-mode analysis, the exact condition for isolation zero is derived. Experimental results for a 5 dB coupler at 0.9 GHz show as much as 33 dB improvements in the directivity over its conventional counterpart.
Keywords :
coupled transmission lines; directional couplers; inductors; asymmetric coupled line backward-wave directional coupler; directivity enhancement; frequency 0.9 GHz; isolation zero; normal-mode analysis; shunt inductor; shunt-inductive loading;
Journal_Title :
Electronics Letters
DOI :
10.1049/el.2010.0214
