This letter proposes an adaptive element grouping method for discrete-phase reconfigurable intelligent surfaces (RISs) serving a high-mobility user equipment (UE) to maximize the average net spectral efficiency. A drift-aware channel state information (CSI) aging model is derived for the RIS-to-UE link, enabling pilot refreshing, CSI prediction, and error covariance characterization. With pilot-training and RIS-reconfiguration overhead included, a two-timescale design is developed: slow-timescale grouping exploits spatial correlation, whereas fast-timescale beamforming and discrete-phase optimization use predicted CSI while retaining residual inter-group coupling. Simulations show higher net spectral efficiency than existing grouping schemes, especially under high mobility and large-scale RISs.
Near-field simultaneously transmitting and reflecting reconfigurable intelligent surface (STAR-RIS) systems enable full-space coverage, but dense multiuser operation requires active-user grouping under practical stream or RF-chain constraints. Gain-based or proportional-fair scheduling may over-serve strong users, whil...
T. Van Le, Trong-Dai Hoang· IEEE Wireless Communications...· 0 citations
This paper proposes an end-to-end mobility-aware multi-RIS optimization framework that integrates per-RIS blockage detection with closed-form Riemannian updates and jointly optimize the BS precoder and RIS phases using a Stochastic Closed-form Riemannian Phase Alignment algorithm.
Sehyun Ryu, Seung-Min Choi, Hyun Jong Yang et al.· 0 citations
New techniques are required to estimate the user-to-reconfigurable intelligent surface (RIS) near-field channel due to the distance-dependency of its steering vector. The estimate is needed to determine the RIS configuration and the combining vector of the multi-antenna base station (BS) receiver. We present a novel, l...
Shivani Dhok, N. Mehta· IEEE Transactions on Communi...· 0 citations
Simulation results position D3QN-PER as a strong candidate for deployment as a near-RT RIC xApp within the O-RAN architecture, advancing the vision of AI-native mobility management for 6G.
Kalpesh Popat, Divyakant T. Meva· Telecommunications Systems· 0 citations
The next generation of wireless systems extends ultra-reliable low-latency communications (URLLC) to the realm of massive connections, termed mURLLC. To address the inherent conflict between stringent quality of service (QoS) requirements in URLLC and the problem of severe and highly fluctuating interference behind dem...
Yi-Chen Guo, Lili Xu, Yihang Cheng et al.· IEEE Transactions on Wireles...· 0 citations
LoRa-LQE, a link quality estimation scheme specifically designed for mobile environments, outperforms state-of-the-art solutions and achieves packet delivery ratio improvements and energy efficiency improvements, thereby enabling more reliable communication for mobile IoT assets.
Geraldo A. Sarmento, T. R. D. Da Silva, Fernando J. V. Santos et al.· Journal of Internet Services...· 0 citations
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