MODELING, SYNTHESIS AND CHARACTERIZATION OF A MILLIMETER-WAVE MULTILAYER MICROSTRIP LIQUID-CRYSTAL PHASE-SHIFTER

Electromagnetic simulation software is used for modeling the propertie s of a 2-15 GHz liquid crystal microstrip phase shifter previously des igned at Thomson-CSF. After experimental validation of the computed re sults, the software is applied to the modeling of a new 30-40 GHz mult ilayer microstrip phase shifter, where the active medium is a liquid c rystal inserted between solid dielectric substrates. Measurements carr ied out at between 10 and 40 GHz on 4.35 cm long lines are in good agr eement with theoretical predictions. A maximum experimental phase shif t of 219.3 degrees at 37 GHz (about 50 degrees/cm) was observed for a structure with a commercial liquid crystal (BDH-E44) and silica substr ates.