Design of a Tunable THz 1-D Leaky-Wave Antenna based on Nematic Liquid Crystals

Abstract

Very few designs are reported in the terahertz range for realizing dynamic beam-steering of the antenna radiation pattern at a fixed frequency. In this work, we propose a one-dimensional leaky-wave antenna based on nematic liquid crystals (NLC). More specifically, an NLC cell is sandwiched between two foam layers, the top one patterned with a partially reflecting sheet (PRS), and the bottom one entirely metalized to have a ground plane. Two lateral perfect magnetic conductor walls allow for a dominant TM leaky mode propagating in the structure. The beam is then steered by applying a low-frequency driving voltage through the ground and the PRS. The trade-off among radiation efficiency, angular steering range, and gain that commonly affects any reconfigurable antenna is properly handled through a suitable choice of the design parameters. Full-wave results are finally provided to demonstrate the concept.