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arXiv · 2506.14385

Performance Characterization of Continuous Reconfigurable Intelligent Surfaces

Amy S. Inwood·Peter J. Smith·Mahmoud AlaaEldin·Michail Matthaiou
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Abstract

We consider a reconfigurable intelligent surface (RIS) that can implement a phase rotation continuously over the whole surface rather than via a finite number of discrete elements. Such an RIS can be considered a design for future systems where advances in metamaterials make such an implementation feasible or as the limiting case where the number of elements in a traditional RIS increases in a given area. We derive the optimal RIS design for the single-user (SU) scenario assuming a line-of-sight (LoS) from the RIS to the base station (BS) and correlated Rayleigh fading for the other links. We also derive the associated optimal signal-to-noise ratio (SNR) and its mean, a bound on the mean spectral efficiency (SE), an approximation to the SNR outage probability and an approximation to the coefficient of variation for the investigation of channel hardening.

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Amy S. Inwood, Peter J. Smith, Mahmoud AlaaEldin, Michail Matthaiou. 2025-06-17. Performance Characterization of Continuous Reconfigurable Intelligent Surfaces. https://arxiv.org/abs/2506.14385

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