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arXiv · 2610.27445

Structured PARAFAC Channel Estimation for Flexible Intelligent Metasurface Receivers

Xi Han·Junqiao Chen·Yuansheng Zhang·André L. F. de Almeida·George C. Alexandropoulos
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Abstract

Flexible intelligent metasurfaces (FIMs) create geometric diversity through aperture morphing, but their configuration-dependent responses complicate uplink channel estimation. This letter considers multiple users sharing a common angular response and develops a structured PARAFAC model across calibrated FIM configurations. Its known identity factor and rank-one pilot-weighted channel factor enable deterministic, noniterative algebraic factor recovery through per-element rank-one approximations, reference-state normalization, global rank-one projection, and a least-squares morphing-factor update. The recovered spatial and morphing factors are then jointly matched to the calibrated manifold to estimate the common angles, user gains, and configuration-dependent channels. Simulations demonstrate accurate recovery and show that out-of-plane morphing resolves the azimuth-sign ambiguity of an undeformed planar aperture; an angular-spread experiment quantifies the mismatch when the common-response assumption is relaxed.

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Xi Han, Junqiao Chen, Yuansheng Zhang, André L. F. de Almeida, George C. Alexandropoulos. 2026-10-20. Structured PARAFAC Channel Estimation for Flexible Intelligent Metasurface Receivers. https://arxiv.org/abs/2610.27445

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