Metamaterial Reverse Fractal Reflector for RIS Application

The purpose of this paper is to present the design and simulation of butterfly-shaped metamaterial reflectors at 12 GHz. The design is derived from fractal iteration that has the reverse angle of the iteration. The metamaterial reflector functions at a wide-ranging operating angle of incident electromagnetic (EM) waves. The Rogers's substrate is used to print a butterfly copper structure on the unit cell of the metamaterial, which is 0.51 mm thick. The simulation results indicate that the metamaterial reflector can reflect up to 40° of incident EM waves, which is more than 85%. For TE mode, the metamaterial structure can maintain 75% reflectance at an operating angle of 60°. The reflector is expected to be employed in reconfigurable intelligence surface (RIS) applications.