Advanced characterization of a W-band phase shifter based on liquid crystals and MEMS technology

Abstract

In this paper, we present a continuously tunable phase shifter realized in MEMS technology. Varactors with liquid crystal as a tunable dielectric layer underneath gold bridges are used to build a loaded line phase shifter. Measurements show that the phase shifter has a differential phase shift of 92°, a figure of merit (FoM) of 42°/dB and an input matching of −19 dB at 76 GHz.The tuning speed of the phase shifter is measured at different temperatures between 10 and 50°C. The realized phase shifter can be used in combination with MEMS switches in order to build a 360° tunable reflection phase shifter.