Electrically Microwave Tunable Components Using Liquid Crystals

Abstract

The study of electrically tunable phase-shifters based on the use of liquid crystals is under consideration. First, the dielectric characterisation of a commercial liquid crystal involved in this study is reported. The anisotropy of such substrates is given by the permittivity tensor. Second, two phase-shifter configurations are studied. Both structures propose inverse strip-line but different accesses and substrates. In addition, phase variation measurements corresponding to these two configurations improve performances.

Influence of design liquid crystal-based devices on the agility capability

“…Coplanar accesses are useful to connect the 3680K Wiltron probes test fixture [7]. For each device, phase-shift and Figure Of Merite (FOM) were determined at 20 GHz.…”

Technological evolution and performances improvements of a tunable phase‐shifter using liquid crystal

“…Components based on the use of electrically tunable LC have been already studied within our laboratory [11]. In this context, the devices proposed here use thick-film technology.…”

Improvement of Phase-Shifting Properties in Coplanar Waveguide-Type Liquid Crystal Millimeter-Wave Phase Shifter by Introducing a Resonant Phenomenon

“…5) The phase shifter is an important device, and planar-type LC phase shifters for microwaves and MMWs have been proposed using microstrip lines. [9][10][11][12][13][14][15][16] Coplanar waveguide (CPW) is well known as an excellent planar-type waveguide for superhigh-frequency electromagnetic waves and has the advantage of simplicity of integration with other electronic devices because both the signal and ground electrodes are on the same surface. A typical sandwich cell structure can be easily constructed on the CPW substrate by almost the same procedure as that used to fabricate LCDs to attain an electrically tunable phase shifter.…”