Tunable millimeter-wave phase shifter based on dielectric elastomer actuation

A very low-loss tunable millimeter-wave phase shifter driven by dielectric elastomer actuators (DEAs) is presented. The device consists of a fixed coplanar waveguide (CPW) and two metallic loading strips suspended on an elastomer membrane. The horizontal offset between the CPW and the strips is dynamically controlled by integrated DEAs. The variable interaction between the CPW and the loading strips results in a change in the effective permittivity, thereby providing analog-controlled true-time-delay. The design, fabrication, and measurements of this phase shifter based on DEAs are presented, demonstrating state-of-the-art phase shift to loss performance, achieving 235 degrees/dB at 35 GHz. (C) 2014 AIP Publishing LLC.