Group reflection‐based reconfigurable intelligent surfaces assisted 6G wireless networks

Abstract Reconfigurable Intelligent Surfaces (RISs) are a key enabler for 6G networks, enhancing spectral efficiency and reliability in non‐line‐of‐sight channels. However, user mobility introduces beam misalignment and phase tracking challenges. This paper proposes the group reflection–based RIS with beam tracking (GR‐RIS‐BT) framework, which integrates group reflection modulation (GRM) with unscented Kalman filter (UKF)–based tracking. The transmitted data are divided into two streams: one configures RIS element groups, while the other conveys modulated symbols. This bit‐splitting mechanism doubles spectral efficiency without significantly increasing complexity. Simulation results show that GR‐RIS‐BT achieves a bit error rate (BER) of 10 −4 at 15 dB SNR using a four‐group RIS, outperforming conventional RIS schemes without beam tracking. Moreover, UKF‐based tracking ensures robust phase alignment under mobility, sustaining low error rates and reliable connectivity. The proposed GR‐RIS‐BT framework offers a scalable and efficient solution for high‐mobility 6G systems by jointly optimizing spectral efficiency, BER, and computational complexity.