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arXiv · 2605.00535

From Pilot to Precoding Design: Blind Angular Spoofing For Location Privacy in MIMO Systems

Priyanka Maity·Lorenzo Italiano·Alireza Pourafzal·Gonzalo Seco-Granados·Hui Chen·Monica Nicoli·Henk Wymeersch
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Abstract

This paper studies location privacy in uplink MIMO systems, where a user equipment seeks to spoof the angular signature observed by a single base station performing localization. We propose a blind analog precoder design that manipulates the perceived angle-of-arrival and angle-of-departure configuration without requiring channel-gain knowledge. The method enforces consistency between the received signal and a desired spoofed angular subspace, and is solved using an alternating optimization algorithm under practical amplitude constraints. Simulations in a multipath scenario show that the proposed approach achieves near-perfect angular spoofing and clearly outperforms pilot-only blind spoofing, which exhibits an error floor. The results also show a trade-off between spoofing accuracy and communication rate, depending on the chosen virtual geometry.

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Priyanka Maity, Lorenzo Italiano, Alireza Pourafzal, Gonzalo Seco-Granados, Hui Chen, Monica Nicoli, Henk Wymeersch. 2026-05-01. From Pilot to Precoding Design: Blind Angular Spoofing For Location Privacy in MIMO Systems. https://arxiv.org/abs/2605.00535

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