Scattering Manipulation for Conformal Coding Metasurfaces Based on a Graphene-Assembled Film

Abstract

Electromagnetic (EM) scattering modulation on arbitrarily shaped platforms is crucial for practical communication systems. Metasurfaces offer significant potential because of their strong EM wave control capabilities. This article presents a conformal array scattering theory (CAST) for precise beam manipulation on 2-D conformal coding metasurfaces (CCMs). Due to the incident wave angle and the curved surface shape, elements exist scattering shadow regions. Therefore, we investigate the spatial direction and distribution of the scattering fields from subarrays composed of 1-bit elements, while analyzing the formation mechanism of the scattering shadow regions. By incorporating wave path and reflection phase changes induced by structural bending, we establish an accurate theoretical model to compute the far-field scattering pattern of CCMs. To validate the approach, a CCM based on a graphene-assembled film (GAF) with ultrahigh conductivity and excellent mechanical properties such as flexibility and lightweight is used to fabricate the designs. The flexible GAF can provide additional spatial freedom through structural bending, enabling curvature-based scattered beam manipulation without requiring other active devices. Theoretical analysis, simulations, and measurements show good agreement, demonstrating the potential of this method for designing conformal arrays for various curved platforms.