Simulation and Fabrication of Broadband Tunable Phase Shifter Based on Transmission Line Metamaterial

This paper presents a kind of broadband, low-loss tunable phase shifter based on transmission line metamaterial. An inherent high-pass backward-wave response property of a left-handed metamaterial based on coplanar waveguide (CPW) transmission line was used to realize a microwave phase shifter. The commercial software Ansoft HFSS was used to design and analyze for the transmission line metamaterial phase shifter structure, and the resulting S-parameters were used to characterize its performance. A transmission line metamaterial phase shifter was fabricated on Copper-Clad Board. The designed four unit-cells phase shifter provides a 0-190o continuous phase shift at 7.2 GHz using varactors biased from 0 V to 6 V with relatively low insertion loss.