Wide‐Angle Conformal Active Metasurface for Dynamic Beam Steering and Orbital Angular Momentum Generation
Haiqing Chen, Tonghao Liu, Mengzhou Chen, Dongshu Wang, Weihan Li, Borui Wu, Long Wang, Long Wang, Gu Liu, Liuying Wang, Liuying Wang
Abstract
Abstract Metasurfaces have intrigued long‐standing research interests and developed multitudinous compelling applications owing to their unprecedented capability for manipulating electromagnetic (EM) waves, and the emerging programmable coding metasurfaces provide a real‐time reconfigurable platform to dynamically implement customized functions. Nevertheless, the passive metasurfaces, once fabricated, lack dynamic tunability, while existing metasurface‐based stealth designs are primarily based on planar metasurfaces, which severely limit their applicability to curved platforms. In this work, an innovative strategy is proposed for conformal active metasurface (CAM) by integrating 3D‐printed curved substrates with voltage‐programmable 2‐bit phase coding. This design enables dual‐functional tunable EM waves functions in adaptive beam steering for radar cross‐section (RCS) enhancement and in vortex wave generation with orbital angular momentum (OAM) for communication from 9.3 to 10.5 GHz. Simulation and experimental results demonstrate that the CAM can deflect incident waves with angles ranging from 0° to 50° in the beam‐steering mode and achieve preset reflection directions with a pointing accuracy of better than ±2°. The RCS is reduced by more than 10 dB along the incident direction, while it is enhanced by up to +8.9 dB in the preset reflection direction, effectively enabling wide‐angle radar stealth for both illusionary stealth and camouflage. In the OAM mode, the CAM generates vortex beams with OAM at 150 mm, which can effectively increase the spectral efficiency of wireless communication systems. This promising design paves the way for the development of intelligent metasurfaces with enhanced serviceability and flexibility, offering tremendous potential for applications in communication, stealth, and other multifunctional smart metadevices.