Survey on Beyond Diagonal RIS Enabled 6G Wireless Networks: Fundamentals, Recent Advances, and Challenges
Abstract
Beyond Diagonal Reconfigurable Intelligent Surfaces (BD-RIS) represent a groundbreaking innovation in sixth-generation (6G) wireless networks, enabling unprecedented control over wireless propagation environments compared to conventional diagonal RIS (D-RIS). This survey provides a comprehensive analysis of BD-RIS, detailing its architectures, operational principles, and mathematical modeling while highlighting its performance benefits. BD-RIS classifications, including single-connected, fully-connected, and group-connected architectures, and their reflective, transmissive, hybrid, and multi-sector operating modes are examined. Recent advances in BD-RIS-enabled 6G networks are reviewed, focusing on critical areas such as channel estimation, sum-rate and spectral efficiency optimization, energy efficiency enhancement, and security. The survey identifies fundamental challenges in BD-RIS research, including hardware design limitations, adaptive channel estimation, and the impact of non-ideal hardware effects. Future research directions for BD-RIS are proposed, emphasizing the integration of artificial intelligence and machine learning (AI/ML), joint optimization of communication and sensing, and enhanced physical layer security (PLS). This study concludes by underscoring BD-RIS's transformative potential to redefine 6G wireless networks, offering valuable insights and lessons for future research and development.
Keywords
Cite
@article{arxiv.2503.08423,
title = {Survey on Beyond Diagonal RIS Enabled 6G Wireless Networks: Fundamentals, Recent Advances, and Challenges},
author = {Wali Ullah Khan and Manzoor Ahmed and Chandan Kumar Sheemar and Marco Di Renzo and Eva Lagunas and Asad Mahmood and Syed Tariq Shah and Octavia A. Dobre and Jorge Querol and Symeon Chatzinotas},
journal= {arXiv preprint arXiv:2503.08423},
year = {2025}
}
Comments
As significant revisions have been requested by one of the co-authors due to certain technical flaws in the paper, and addressing these concerns will require substantial time, we kindly request the complete withdrawal of the current version from the arXiv platform until the corrected version is ready