Intelligent Omni-Surfaces: Simultaneous Refraction and Reflection for Full-Dimensional Wireless Communications

The development of metasurfaces has unlocked various use cases in wireless communication networks to improve performance by manipulating the propagation environment. Intelligent omni-surface (IOS), an innovative technique this category, is proposed for coverage extension. In contrast widely studied reflective metasurfaces, i.e., intelligent reflecting surfaces (IRSs), which can only serve receivers located on same side transmitter, IOS achieve full-dimensional communications enabling simultaneous reflection and refraction surface, thus users both sides be served. paper, we provide a comprehensive overview state-of-the-art from perspective communications, with emphasis their design principles, channel modeling, beamforming design, experimental implementation measurements, as well possible applications future cellular networks. We first describe basic concepts introduce corresponding principles different types metasurfaces. Moreover, elaborate reflective-refractive model each element IOS-aided systems. Furthermore, show how three scenarios. particular, present prototype report its measurement results. Finally, outline some potential directions challenges area.