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arXiv · 2608.13436

Low-Complexity Channel Parameter Estimation for Coprime HRIS-Assisted MIMO Systems

Jean C. S. Ferreira·Melryllin G. O. Sousa·Fazal-E Asim
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Abstract

This paper proposes a parameter estimation scheme for uplink MIMO systems assisted by a Hybrid Reconfigurable Intelligent Surface (HRIS). To reduce hardware complexity, the HRIS employs a small number of active elements arranged in a sparse coprime geometry for local sensing, while the remaining elements passively reflect signals. This simultaneous sensing and reflection significantly improves accuracy over fully passive architectures. The method leverages Khatri-Rao and Kronecker factorizations to efficiently decouple the cascaded channel at the base station. Furthermore, spatial smoothing resolves the coprime array rank deficiency, enabling robust angular extraction via Root-MUSIC. Simulations demonstrate highly resilient estimation performance across scenarios.

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Jean C. S. Ferreira, Melryllin G. O. Sousa, Fazal-E Asim. 2026-08-13. Low-Complexity Channel Parameter Estimation for Coprime HRIS-Assisted MIMO Systems. https://arxiv.org/abs/2608.13436

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