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arXiv · 2403.09275

Static Grouping Strategy Design for Beyond Diagonal Reconfigurable Intelligent Surfaces

Matteo Nerini·Shanpu Shen·Bruno Clerckx
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Abstract

Beyond diagonal reconfigurable intelligent surface (BD-RIS) extends conventional RIS through novel architectures, such as group-connected RIS, with scattering matrix not restricted to being diagonal. However, it remains unexplored how to optimally group the elements in group-connected RISs to maximize the performance while maintaining a low-complexity circuit. In this study, we propose and model BD-RIS with a static grouping strategy optimized based on the channel statistics. After formulating the corresponding problems, we design the grouping in single- and multi-user systems. Numerical results reveal the benefits of grouping optimization, i.e., up to 60% sum rate improvement, especially in highly correlated channels.

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Matteo Nerini, Shanpu Shen, Bruno Clerckx. 2024-03-14. Static Grouping Strategy Design for Beyond Diagonal Reconfigurable Intelligent Surfaces. https://arxiv.org/abs/2403.09275

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