Reconfigurable Transmissive Metasurfaces for High Efficiency Dynamic Beamforming

Reconfigurable intelligent surfaces (RISs) have emerged as a pivotal technology for 6G networks, distinguished by their ability to dynamically manipulate electromagnetic (EM) wave propagation. In this paper, we propose a transmissive RIS architecture integrated with PIN diodes, enabling 1-bit digital phase modulation through programmable control of diode switching states. Dynamic beamforming is accomplished via a binary coding strategy, where beam directions are reconfigured by tailoring spatial coding patterns. Full-wave electromagnetic simulations reveal that the metasurface achieves beam splitting at 30° and 45° by selectively switching PIN diodes between ON and OFF states, sustaining transmission efficiencies exceeding 75% in both operational modes. The results demonstrate robust beam control performance, while the digitally programmable nature of the design highlights its potential for intelligent wavefront engineering in future 6G communication systems, particularly in scenarios requiring adaptive signal routing and multi-beam optimization.