▎ 摘　　要

In this paper, the radiation characteristics of frequency tunable graphene based metamaterial reflectarray have been investigated. The unit-cell consists of graphene two gaps split-ring-resonator (SRR) printed on a thick SiO2 substrate. The metamaterial parameters of the unit-cell have been calculated at different graphene chemical potentials and different SRR gaps. Using waveguide simulator, the reflection coefficient phase of the graphene metamaterial reflectarray unit-cell has been investigated. A 13x13 graphene metamaterial reflectarray antenna fed by a circular horn antenna is designed and analyzed at different graphene chemical potentials. Full-wave analysis for the graphene metamaterial reflectarray antenna has been applied using the finite integration technique.