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arXiv · 2609.28402

Robustness Guarantees for Optimal RIS Placement in Self-Localization Under Placement Errors

Mahdi Koloushani·Omid Rezaei·Seyed Mohammad Karbasi·Mohammad Mahdi Naghsh·Mohammad Mahdi Nayebi
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Abstract

This paper studies the effect of Reconfigurable Intelligent Surface (RIS) placement errors on optimal RIS deployment for Time-of-Flight (ToF)-based self-localization. We consider a setup in which a source transmits a signal, receives the RIS-reflected echo, and estimates its own position from the corresponding ToF measurements. Under the conditions of moderate, i.i.d. Gaussian RIS position errors and i.i.d. Gaussian ToF noise, we demonstrate that the placement uncertainty manifests as a geometry-independent scaling factor in the Cramér-Rao Bound (CRB). Consequently, we prove that the optimal RIS placement remains unchanged by the presence of RIS position errors. This result is established for A-, D-, and E-optimality criteria. Simulation results verify the analysis and show that optimized RIS deployments retain their advantage even in the presence of placement uncertainty.

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Mahdi Koloushani, Omid Rezaei, Seyed Mohammad Karbasi, Mohammad Mahdi Naghsh, Mohammad Mahdi Nayebi. 2026-09-23. Robustness Guarantees for Optimal RIS Placement in Self-Localization Under Placement Errors. https://arxiv.org/abs/2609.28402

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