A 1-Bit Single Layer Transmitarray for Radiation Pattern Reconfiguration at 100 GHz Using Optical Control of Phase Change Materials

We present the design and performances of a transmitting antenna array (Transmit-array) operating at 100 GHz, enabling radiation pattern reconfiguration by integration of GeTe phase-change materials (PCMs). The overall device is proposed as a simple single-layer structure in which the elementary cells are spaced by lambda/2 in both planar directions and are consisting of a metal split-ring resonator printed on a dielectric substrate and integrating patterns of the GeTe material. The radiation pattern reconfiguration is achieved by specific distributions of dissimilar unit cells having 180° phase shift between them. This phase shift is achieved by alternating between the amorphous and crystalline states of the GeTe patterns within the split rings using laser optical activation.