Scalable 32 × 32 1-Bit Reconfigurable Intelligent Surfaces for Upper-Mid Band 6G Communications

Recently, reconfigurable intelligent surfaces (RIS) have been recognized as an important technology to overcome non-line-of-sight (NLOS) situations beyond 5G and 6G wireless communications. In this paper, we design a 1-blt RIS unit cell with low loss and wide phase shift bandwidth in the upper-mid band 8 GHz. We fabricated a 4 × 4 unit array with 16 unit cells and scaled it to make a 32 × 32 RIS. We also proposed the gain of the RIS that can be incorporated into the friis transmission equation, and verified the gain of the proposed RIS through measurements.