Reconfigurable Microwave Phase Shifter Based on Nematic Liquid Crystal: Design and Experimental Validation

In this paper, a low-cost microstrip line structure microwave phase shifter based on nematic liquid crystal materials is discussed. The device is built on a glass substrate: the two ports of this device have the coplanar waveguides (CPWs) with 50Ω impedance structure to feed the energies or extract signals at both ends of the phase shifter. The simulation validate the phase shift can reach 360 degrees, and the S21 parameter reaches -4.5dB in the frequency band 28-30Ghz. The practical device shows S21 insertion loss is -12~-15dB, the phase shift can reach 360 degrees, and it works well between +10°C~+65 °C. The phase-shifting repetition accuracy is less than 1 degree.