A General and Efficient Framework for the Rapid Design of Miniaturized, Wideband, and High-Bit RIS

Abstract

High-performance reconfigurable intelligent surfaces (RISs) are growing in significance for practical applications. However, current design methods typically accommodate one or two properties of RISs, and reliance on time-consuming and burdensome full-wave simulations slows down design efficiency. To overcome these limitations, we propose a general and efficient framework for the rapid design of high-performance RISs. It integrates advanced antenna design techniques and incorporates various load types, quantities, and values to achieve the design of high-performance RISs. To boost efficiency, the framework leverages a multi-port network model to quickly obtain the electromagnetic (EM) responses of RIS units with various loads and employs the genetic algorithm for fast optimization of desired units. For validation, we designed a miniaturized, wideband, and high-bit RIS unit using this framework. It achieves 4-bit phase modulation, 23% relative bandwidth and a λ/5 size. A RIS prototype with a size of 20×10 was designed, simulated, and measured based on this unit. All results are in good agreement, demonstrating effective beam scanning from -50° to 50°. The entire design process takes only 1.2 hours and one full-wave EM simulation. This framework enables rapid high-performance RISs design, facilitating their large-scale applications in communication and radar systems.