Design of a Novel 2-bit Wideband Beam-Scanning Reconfigurable Intelligent Surface

Reconfigurable Intelligent Surface (RIS) is regarded as a critical technology for future wireless communications. In this paper, a novel 2-bit wideband RIS with 16×16 elements is presented. The structure of an element is composed of two parts, namely a microstrip antenna and a stripline. Two PIN diodes are employed to realize 4 types of phase and then tune the effective resonance length of the RIS element. A 16×16 RIS array is developed in HFSS software, and the full-wave simulation results of RIS array showing that beam scanning from 0° to 60° is realized at 5GHz. Also, -3dB bandwidth from 4.8GHz to 5.5GHz is obtained when scanning angle is set at 0 degree.