Phase characterization of reconfigurable reflectarray antennas

Abstract

The design and performance optimization of X-band reconfigurable reflectarray antennas have been discussed in this paper concentrating mainly on the phase characteristics. Liquid crystals based substrates and slot embedded patch elements have been proposed as two different techniques for the design of reflectarrays with frequency tunability characteristics. Reflectarray patch elements constructed on anisotropic liquid crystal substrate are proposed to be employed as a dynamic phase control strategy for terrestrial systems. A detailed analysis of dynamic phase range and frequency tunability with respect to dielectric anisotropy is presented for two different anisotropic liquid crystal substrate materials. The investigated liquid crystals substrates provided a maximum reduction of 14.1% in volume for reflectarray design at 10 GHz. Moreover rectangular slots on the patch elements are shown to offer a maximum frequency tenability of 1.7GHz. The Finite Integral Method (FIM) validated by waveguide scattering parameter measurements demonstrated a dynamic phase range of 314° and a volume reduction of up to 24.36%.