Preliminary design of a liquid crystal-based reflectarray antenna for beam-scanning in THz

A 50.22 × 48.6 mm beam-scanning reflectarray based on liquid crystals (LCs) has been designed to operate over a bandwidth of 5.5% in the low THz frequency range. The structure consists of a single-layer multi-resonant periodic array with unit-cells composed of three parallel unequal length dipoles. The gap between the array and ground plane is filled with electronically tunable LC which exhibits a permittivity value that is controlled by a low frequency bias signal. The simulations demonstrate that the beam can be scanned over an angular range of ±10° yielding a gain greater than 35 dBi and maximum sidelobe levels of 25 dB from 335 to 354 GHz.