A Full-Duplex Metasurface for Simultaneous and Independent Control of Radiation and Reflection

Abstract

Metasurfaces have transformed electromagnetic interfaces from fixed, material-defined boundaries into engineered platforms for tailoring wave propagation, spanning both passive designs and actively programmable implementations. For future information systems, a central challenge is to make the same physical aperture operate simultaneously as a radiating antenna and a reconfigurable reflector. Radiation–reflection-integrated (R2I) metasurfaces combine these functions, but their responses remain coupled: configuring the surface for radiation constrains its behavior in reflection. They therefore cannot generally provide independent operation at the same time, frequency, and polarization. Here, we show an intelligent full-duplex R2I metasurface that overcomes this constraint. The surface integrates controllable meta-atoms with a substrate-integrated waveguide (SIW). Because the SIW-guided and free-space excitations occupy largely separated regions of the spatial spectrum, the radiated and reflected fields can be manipulated simultaneously and independently on the same aperture. We experimentally demonstrate this capability in integrated sensing and communication and in integrated detection and stealth, both realized using a single artificial-intelligence-assisted metasurface under identical operating conditions. These results establish a route towards full-duplex, single-aperture information systems.