A Novel 2-Bit Graphene Reconfigurable Reflectarray

We present a novel 2-bit graphene-controlled reconfigurable antenna design for large-scale, millimeter-wave/terahertz reflective surfaces. Using previously characterized graphene sheet resistances, in the millimeter-wave bands, the proposed 2-bit configuration can be used for reconfigurable reflective surfaces, while reducing the quantization lobes compared to 1-bit designs with a small increase in the complexity and losses. As such, we place two, single-bit, graphene phase shifters on each differential node of a patch antenna, achieving lower insertion losses and 2-bit phase control on the reflected waves. Herein, we present the theoretical models of the proposed designs alongside full-wave simulations of a 275 GHz linear array.