Metamaterials and metasurfaces are a class of materials engineered to have properties not typically found in nature. The word “metamaterial” derives from the Greek words “meta” (meaning beyond) and “materia” (meaning matter), signifying their ability to transcend the physical limitations of conventional materials. Metasurfaces are essentially the 2D counterparts of metamaterials, engineered to manipulate electromagnetic waves in ways that classical materials cannot. These surfaces are at the forefront of transformative technologies such as reconfigurable surfaces, Huygens’ surfaces, coding metasurfaces, and more.
Advancements in metasurface engineering have led to applications in diverse areas such as negative refraction, cloaking, scattering cancellation, and nonreciprocal optical activity. Their key advantages over traditional technology include a thinner profile, easy integration, reduced deployment and maintenance costs, and enhanced flexibility in tuning electromagnetic behavior.
At RFSAT, we have made significant strides in this field. We were the first in the UK to demonstrate a fully functional Reconfigurable Reflecting Surface (RRS) operating in the sub-6GHz band. This surface can dynamically reconfigure its electromagnetic aperture to address coverage challenges in 6G networks. Furthermore, we have demonstrated a static version based on holographic theory, capable of eliminating coverage blind spots at known locations without requiring external power. Ongoing research is focused on designing metasurfaces for mmWave and THz frequencies to enhance outdoor-to-indoor (O2I) coverage, further advancing the capabilities of beyond-5G communications. Our work is considered groundbreaking and has generated significant interest within the wireless community.