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arXiv · 2502.12916

Beyond Diagonal RIS for ISAC Network: Statistical Analysis and Network Parameter Estimation

Thanh Luan Nguyen·Georges Kaddoum·Bassant Selim·Chadi Assi
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Abstract

This paper investigates the use of beyond diagonal reconfigurable intelligent surface (BD-RIS) with $N$ elements to advance integrated sensing and communication (ISAC). We address a key gap in the statistical characterizations of the radar signal-to-noise ratio (SNR) and the communication signal-to-interference-plus-noise ratio (SINR) by deriving tractable closed-form cumulative distribution functions (CDFs) for these metrics. Our approach maximizes the radar SNR by jointly configuring radar beamforming and BD-RIS phase shifts. Subsequently, zero-forcing is adopted to mitigate user interference, enhancing the communication SINR. To meet ISAC outage requirements, we propose an analytically-driven successive non-inversion sampling (SNIS) algorithm for estimating network parameters satisfying network outage constraints. Numerical results illustrate the accuracy of the derived CDFs and demonstrate the effectiveness of the proposed SNIS algorithm.

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Thanh Luan Nguyen, Georges Kaddoum, Bassant Selim, Chadi Assi. 2025-02-18. Beyond Diagonal RIS for ISAC Network: Statistical Analysis and Network Parameter Estimation. https://arxiv.org/abs/2502.12916

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