Research On Terahertz Reflective Phase Shifter And Antenna Based On Liquid Crystal

Nowadays,devices that enable continuous frequency regulation are gaining more and more attention.There are three main approaches to frequency regulation: mechanical drives,integrated circuit design,and tunable materials which can achieve continuous frequency adjustment at lower bias voltage.In this paper,the study of the terahertz reflective phase shifter is carried out based on the birefringence of liquid crystal in the terahertz band.The multi-resonator phase shifter is used as the unit to simulate the liquid crystal-based reflective array antenna.In this paper,the simulation of the terahertz reflective phase shifter based on liquid crystal is carried out.The principle of the reflective phase shifter and the factors influencing the phase-shifting characteristics are studied.Single dipole reflective phase shifter and single ring reflective phase shifter based on liquid crystals are designed,and device processing and experimental tests are also performed.The differences between experimental results and simulation results are analyzed.According to the characteristics of dielectric anisotropy and inhomogeneity of liquid crystal material,single dipole reflective phase shifter and single ring reflective phase shifter were accurately modeled.Compared with the simulation results of ordinary models,the phase-shifting range will be reduced more than 50° by the accurate model,and the accuracy of the accurate model was proved by the experimental results.It can be seen that the accuracy of the phase-shifting range improved more than 20% by the accurate model.Three multi resonant reflective phase shifters operating in the terahertz band have been designed based on the study of the single resonant structure.They have larger bandwidth and higher phase-shifting range than the single resonant unit.And a terahertz reflective array antenna based on liquid crystal is designed by using the "H"-shaped phase shifter as the unit of the antenna.