Graphene-Based Reconfigurable Intelligent Surface for 6G Wireless Communication

The exponential growth in wireless communication demands has driven the search for innovative solutions for next-generation wireless networks beyond 5G. Terahertz (THz) communications have emerged as a prime contender for facilitating ultra-high speed data transmission for the sixth-generation (6G) wireless era. To address the challenges associated with the THz signal propagation, serious path loss, and blockage vulnerability, this manuscript presents the concept of graphene-based reconfigurable intelligent surface (GRIS) as a transformative technology for enhancing THz communication in 6G systems. The surface conductivity of the GRIS unit cell element is adjusted by controlling the chemical potential (eV) of the graphene. The RIS unit cell consists of a square patch of graphene material mounted on a quartz substrate having a dielectric constant of 3.75 and loss tangent of 0.0004. The reflection coefficient amplitude (dB) and phase (degree) characteristics of the unit cell are analysed by controlling the chemical potential (0eV-2eV) in the frequency range of 1.4 THz-1.8 THz. The proposed model is insensitive to the angle of incidence and polarization. Hence unit cell is designed for both TE & TM polarizations along with different angles of incidence and has achieved almost stable reflection amplitude in the operating band.