Compact Distributed Phase Shifters at X-Band Using BST

Abstract

A new type of distributed analog phase shifter is presented that utilizes the coplanar strip transmission line topology. This transmission line has several benefits for phase shifter design, resulting in decreased physical dimensions and potentially lower losses. A prototype was constructed using thin-film barium strontium titante (BST) varactor technology. The design achieved a 49• /dB figure of merit at 10 GHz. The performance and chip area of the coplanar strip circuit are compared with designs using coplanar waveguide and synthetic lumped element transmission lines.

Graded ferroelectric capacitors with robust temperature characteristics

“…[1][2][3][4][5][6] However, the dielectric behavior of these materials depends very strongly on temperature near the Curie temperature T C . This means that, for conventional ferroelectrics, the dielectric properties of the tunable devices may drift strongly depending on ambient conditions.…”