# CSI Obfuscation: Single-Antenna Transmitters Can Not Hide from Adversarial Multi-Antenna Radio Localization Systems

arXiv: https://arxiv.org/abs/2508.02553 · HTML: https://mlsanity.com/paper/2508.02553/

## Key facts

- No citing papers in the map yet (data through 14 Oct 2026).
- Builds on 13 of its 23 references that are in the map.
- First posted on arXiv 4 Aug 2025.

## Builds on (most cited first, 13 of 13)

- [Channel Charting: Locating Users within the Radio Environment using Channel State Information](https://mlsanity.com/paper/1807.05247/) (2018)
- [Deep Convolutional Neural Networks for Massive MIMO Fingerprint-Based Positioning](https://mlsanity.com/paper/1708.06235/) (2017)
- [A Distributed Massive MIMO Channel Sounder for "Big CSI Data"-driven Machine Learning](https://mlsanity.com/paper/2206.15302/) (2022)
- [Angle-Delay Profile-Based and Timestamp-Aided Dissimilarity Metrics for Channel Charting](https://mlsanity.com/paper/2308.09539/) (2023)
- [DNN-based Localization from Channel Estimates: Feature Design and Experimental Results](https://mlsanity.com/paper/2004.00363/) (2020)
- [On Deep Learning-based Massive MIMO Indoor User Localization](https://mlsanity.com/paper/1804.04826/) (2018)
- [Fingerprinting-Based Positioning in Distributed Massive MIMO Systems](https://mlsanity.com/paper/1509.00202/) (2015)
- [Et Tu Alexa? When Commodity WiFi Devices Turn into Adversarial Motion Sensors](https://mlsanity.com/paper/1810.10109/) (2018)
- [Augmenting Channel Charting with Classical Wireless Source Localization Techniques](https://mlsanity.com/paper/2312.01968/) (2023)
- [Attacking and Defending Deep-Learning-Based Off-Device Wireless Positioning Systems](https://mlsanity.com/paper/2211.08291/) (2022)
- [A Study of MAC Address Randomization in Mobile Devices and When it Fails](https://mlsanity.com/paper/1703.02874/) (2017)
- [Stay Connected, Leave no Trace: Enhancing Security and Privacy in WiFi via Obfuscating Radiometric Fingerprints](https://mlsanity.com/paper/2011.12644/) (2020)
- [Geometry-Based Phase and Time Synchronization for Multi-Antenna Channel Measurements](https://mlsanity.com/paper/2206.05984/) (2022)

## Abstract (arXiv)

The ability of modern telecommunication systems to locate users and objects in the radio environment raises justified privacy concerns. To prevent unauthorized localization, single-antenna transmitters can obfuscate the signal by convolving it with a randomized sequence prior to transmission, which alters the channel state information (CSI) estimated at the receiver. However, this strategy is only effective against CSI-based localization systems deploying single-antenna receivers. Inspired by the concept of blind multichannel identification, we propose a simple CSI recovery method for multi-antenna receivers to extract channel features that ensure reliable user localization regardless of the transmitted signal. We comparatively evaluate the impact of signal obfuscation and the proposed recovery method on the localization performance of CSI fingerprinting, channel charting, and classical triangulation using real-world channel measurements. This work aims to demonstrate the necessity for further efforts to protect the location privacy of users from adversarial radio-based localization systems.