Title :
Modified Vertically Installed Planar Couplers for Ultrabroadband Multisection Quadrature Hybrid
Author :
Chen, Hui-Chun ; Chang, Chi-Yang
Author_Institution :
Dept. of Commun. Eng., Nat. Chiao Tung Univ., Hsinchu
Abstract :
In this letter, we describe a five-section ultrabroadband 1-9GHz microstrip quadrature hybrid (90deg, -3dB coupler), which uses two types of modified vertically installed planar (VIP) couplers and is suitable for conventional printed circuit board realization. The modified VIP couplers provide not only a way to implement tight coupling value with reduced modal phase velocity difference but also a layout flexibility to minimize the discontinuity between sections. An experimental circuit is designed and fabricated with a passband ripple of plusmn0.5dB, a return loss of less than -20dB, and an isolation of better than 20dB over the frequency of 1-9GHz. Very good agreement between the simulated and measured results is obtained
Keywords :
microstrip couplers; microstrip lines; ultra wideband technology; 1 to 9 GHz; modal phase velocity; printed circuit board; return loss; tight coupling value; ultrabroadband microstrip quadrature hybrid; ultrabroadband multisection quadrature hybrid; vertically installed planar coupled line; vertically installed planar coupler; Circuit simulation; Couplers; Coupling circuits; Dielectric substrates; Directive antennas; Frequency; Microstrip; Microwave antenna arrays; Phased arrays; Strips; Modified vertically installed planar (VIP) coupler; VIP coupled line; multisection hybrid; quadrature hybrid;
Journal_Title :
Microwave and Wireless Components Letters, IEEE
DOI :
10.1109/LMWC.2006.879491
