(Web Desk) - Wi-Fi is no longer just for internet access. A new system named WhoFi uses how the human body alters radio waves to identify a person with up to 95.5 percent rank 1 accuracy, according to a new study. It runs on consumer grade gear and still works in poor light. The approach relies on radio measurements, not cameras.

HOW THE WHOFI SYSTEM WORKS The idea is simple to state but technical under the hood. A WhoFi deployment captures Channel State Information (CSI), the fine-grained description of how a Wi-Fi signal changes as it moves through a room and around a person. It then turns those changes into a compact biometric signature that is unique to that individual. The work comes from Danilo Avola, of the Sapienza University of Rome, whose team built and tested the pipeline on public data.

The team reports that Wi-Fi is not just a stand-in for cameras, but offers different strengths that visual systems lack. CSI is a matrix of amplitudes and phases across antennas and subcarriers. In plain terms, it captures tiny differences in how radio energy arrives at the receiver, which encode body shape and motion. Those CSI sequences feed a deep network that learns a person-specific embedding.

The best results came from a Transformer encoder that excels at long-range temporal patterns in the signal. WHAT THE DATA SAY The researchers evaluated WhoFi on the NTU-Fi Human ID benchmark, which contains recordings of 14 subjects performing short walks under different clothing conditions. The NTU-Fi Human ID dataset includes measurements captured with higher resolution CSI tools that expose many subcarriers, allowing finer distinctions between people. WhoFi’s top line result is a 95.5 percent rank 1 identification rate, with a mean average precision of 88.4 percent on the test split.

The WhoFi team kept the system purely academic so far. They trained with public data, documented every step, and compared encoders in a reproducible way.