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A planar reflectarray antenna based on liquid crystal materials is presented in this paper. First, a new type of loop dipole miniaturized liquid crystal antenna reflection unit is constructed. The reflector unit can achieve 400° phase shift at 35GHz, and the loss is less than 4.5dB. Then, an 11×11 liquid crystal reflectarray antenna is designed using this unit, and the main beam scanning angle range of the array antenna reached ±20°. When the deflection angle of the array antenna is 20°, the gain of the antenna is 14.9dBi, and the first sidelobe level is −9.1dB.

This paper designs a miniaturized reflective phase shifter based on liquid crystal. The phase shifter adjusts the dielectric constant of the liquid crystal to cause the load impedance to change, thereby realizing the phase change at the output of the coupler. Through the multilayer circuit structure, the miniaturization of the phase shifter is realized. In the operating bandwidth of 14GHz∼16GHz, the return loss is better than −10.89dB, the insertion loss is better than 5.7dB, and the maximum phase shift exceeds 320°.

In this paper, a terahertz phase shifter work in F-band (90–140 GHz) is designed based on the continuous tunability of liquid crystal and the excellent electrical properties of non radiative dielectric (NRD) waveguide. The simulation results show that the liquid crystal phase shifter is electrically controlled by the bias electrode network, and the maximum phase shift is 500 degrees. The phase shifter shows excellentl matching, and the return loss is almost less than −10 dB in the bandwidth up to 60 GHz.

Because the liquid crystal material has fluidity and electrical control characteristics, it is suitable for conformal phased array design, this paper designed a cylindrical conformal phased array antenna based on liquid crystal material. The designed conformal phased array antenna has a center frequency of 15GHz, a 5×5 uniform array, and a cylindrical radius of 80mm, which can achieve gradient gain scanning (14.17dBi-21.4dBi), and the scanning range is ±30°. The designed antenna array has certain practical prospects.