Reconfigurable Intelligent Surface for Indoor Wireless Communication in the 5 GHz Frequency Band: Design and Characterization

An advanced design and electromagnetic characterization of a Reconfigurable Intelligent Surface (RIS) is introduced for indoor wireless communication enhancement in the 5 GHz band. The proposed RIS comprises a multi-layered metasurface incorporating optimized oval resonators designed to maximize reflection and beamforming capabilities. The analysis employs Floquet theory to examine periodic modal behavior, enabling a comprehensive evaluation of wave interaction mechanisms. Full-wave simulations using the CST Studio Suite assess key performance metrics, including the reflection coefficient (S₁₁), radiation efficiency, directivity patterns, and polarization response. The RIS structure, consisting of a 10×10 array of unit cells, achieves an optimized S₁₁ parameter of -20.7 dB at 5 GHz with controlled beam steering capabilities. A parametric study evaluates the influence of geometrical variations on the resonance characteristics, demonstrating enhanced adaptability for real-world deployments. The results indicate significant improvements in the propagation of WiFi signals, particularly in environments with high structural obstructions. Future work will focus on experimental validation and dynamic tunability for next-generation wireless communication networks.