Design and experimental evaluation of a reconfigurable intelligent surface for wireless applications

• Circular dumbbell-shaped RIS enhances beam steering in mmWave (32.8GHz). • 32×32 simulated, 16×16 prototype validates phase reconfiguration efficiency. • 1-bit AlGaAs PIN diode enables 180° phase shift for precise wavefront control. • Experiment confirms RIS effectiveness in path loss mitigation and scalability. Reconfigurable Intelligent Surfaces (RIS) have emerged as a transformative technology for enhancing wireless communication beyond 5 G and 6 G networks by dynamically manipulating signal propagation. This paper presents a novel RIS design featuring a circular dumbbell-shaped structure, simulated at a large scale of 32×32 elements, addressing the critical challenge of path loss in mmWave communication. Unlike conventional designs, our approach optimizes phase reconfiguration to enhance beam steering efficiency with a low-cost and efficient design. To validate our design, we conduct an experimental study on a 16×16 phase reconfigurable RIS prototype operating at 32.8 GHz in indoor environments. Each unit cell integrates an AlGaAs PIN diode, enabling 1-bit phase control with a 180° phase shift, ensuring precise wavefront manipulation. Our experimental results confirm the effectiveness of the proposed RIS in beam steering and path loss mitigation, demonstrating its practical feasibility for real-world deployments. This study provides new insights into RIS scalability, design optimization, and high-frequency performance, paving the way for its integration into next-generation wireless communication systems.