Physics Practical Magic

Your standard Wi-Fi can now track you through a building with insane accuracy without even knowing the floor plan.

March 19, 2026

Original Paper

WiSLAT: A Simultaneous Device Localization and Target Tracking Method for Wi-Fi Systems

Chunxi Chen, Jingwen Zhang, Chao Yu, Fan Liu, Rui Wang

arXiv · 2603.17283

The Takeaway

Most tracking systems require knowing the exact location of signal 'anchors' to calculate position. This new method uses tiny Doppler shifts in Wi-Fi signals bouncing off a person's body to simultaneously map the environment and track their path, proving that basic wireless signals already contain enough hidden data to turn any home into a motion sensor with zero setup.

From the abstract

It has been shown that the channel state information (CSI) of a Wi-Fi system can be exploited to localize Wi-Fi devices or track trajectory of a moving target. In the existing literature, both sensing tasks are treated separately and some prior information is usually requested, including the signal fingerprints, the locations of some anchor devices in the Wi-Fi system, and etc. In the proposed WiSLAT method, however, it is shown that both sensing tasks can assist each other, such that the reques