X-Band Phased Array Antenna Using Ferroelectric (Ba,Sr)TiO3 Coplanar Waveguide Phase Shifter

• Published in: ETRI journal Vol. 27; no. 6; pp. 677 - 684
• Main Authors: Moon, Seung Eon, Ryu, Han Cheol, Kwak, Min Hwan, Kim, Young Tae, Lee, Su‐Jae, Kang, Kwang‐Yong
• Format: Journal Article
• Language: Korean; English
• Published: 한국전자통신연구원 01.12.2005; ETRI
• Subjects: Ferroelectric phase shifter; impedance matching; phased array antenna; 전자/정보통신공학; impedance matching; ferroelectric phase shifter; phased array antenna
• ISSN: 1225-6463; 2233-7326
• DOI: 10.4218/etrij.05.0105.0024

A phased array antenna was fabricated using four‐element ferroelectric phase shifters with a coplanar waveguide (CPW) transmission line structure based on a Ba0.6Sr0.4TiO3(BST)/MgO structure. Epitaxial BST films were deposited on MgO (001) substrates by pulsed laser deposition. To attain the large differential phase shift and small losses for a ferroelectric CPW phase shifter, an impedance‐matching‐part adding technique between the effective transmission line and connecting cable was used. The return loss and insertion loss for this technique‐adapted BST CPW device were improved with respect to those for a normal BST CPW device. For an X‐band phased array antenna system consisting of ferroelectric BST CPW phase shifters, power divider, dc block, patch antenna, and programmed dc power, the steering beam could be tilted by 15° in either direction.