Digital Twin Aided RIS Communication: Robust Beamforming and Interference Management

TL;DR

This paper introduces a digital twin-based method for RIS communication that approximates channels via electromagnetic models, enabling robust beamforming and interference management without explicit channel estimation, significantly outperforming traditional beam sweeping.

Contribution

The paper presents a novel digital twin approach for RIS channels that reduces estimation overhead and enhances interference management in multi-user wireless networks.

Findings

Achieves desired rates over 90% of the time with the proposed method.

Outperforms beam sweeping, which achieves the same rates less than 8% of the time.

Provides a robust transmission design that accounts for digital twin approximation errors.

Abstract

Reconfigurable intelligent surfaces (RISs) are envisioned to play a key role in future wireless communication networks. However, channel estimation in RIS-aided wireless networks is challenging due to their passive nature and the large number of reflective elements, leading to high channel estimation overhead. Additionally, conventional methods like beam sweeping, which do not rely on explicit channel state information, often struggle in managing interference in multi-user networks. In this paper, we propose a novel approach that leverages digital twins (DTs) of the physical environments to approximate channels using electromagnetic 3D models and ray tracing, thus relaxing the need for channel estimation and extensive over-the-air computations in RIS-aided wireless networks. To address the digital twins channel approximation errors, we further refine this approach with a DT-specific robust transmission design that reliably meets minimum desired rates. The results show that our method secures these rates over 90% of the time, significantly outperforming beam sweeping, which achieves these rates less than 8% of the time due to its poor management of transmitting power and interference.