Wi-Fi technology can now spot you in a room by reading how you move and stand, challenging what privacy means

Hindustan Times

a day ago

What if we told you that researchers at La Sapienza University of Rome have introduced a new way to identify individuals by analysing how their bodies affect Wi-Fi signals? Sounds made up, right? But it's real. This system is called WhoFi and works without cameras, microphones, or the person carrying any device. It detects unique changes in wireless signals caused by a person's size, shape, and movement. WhoFi can identify who is present just from Wi-Fi signal changes in a room, sparking debate over privacy and consent.(Unsplash)
How does it work?
Wi-Fi signals spread through spaces and bounce off or are absorbed by objects, including people. Everyone's body interacts with these signals in a slightly different way. WhoFi captures these small changes by measuring details like signal amplitude and phase. The system then uses a neural network to learn each person's unique signal patterns. The researchers used a dataset known as NTU-Fi, which is a standard for testing Wi-Fi sensing technology. They trained the system to recognise when the same person moves between rooms or different locations. The method achieved a high accuracy rate of up to 95.5 per cent in re-identifying people.
Unlike cameras and microphones, Wi-Fi-based sensing does not capture images or sounds. This can be better for privacy as it avoids collecting explicit personal data. However, some privacy concerns remain. People may be tracked or monitored without knowing which raises ethical questions about consent and surveillance. The researchers stress that WhoFi does not directly collect biometric or personal information. Still, they warn that if used without clear safeguards, the technology could cause covert tracking in homes, workplaces, or public areas, creating new privacy risks.
What are the applications of this technology?
Currently, the technology remains in research labs and is not deployed commercially or by governments. But as Wi-Fi networks become more widespread in homes and cities, this form of identification could become practical and common. Potential uses include security systems that recognise authorised people without cameras, health monitoring that tracks movement and behaviour, or smart environments that adjust settings based on who is present.
There is still much work to do in developing secure and ethical uses of this system. Controls and regulations will need to ensure that tracking technologies respect privacy and user rights. WhoFi shows that Wi-Fi signals can reveal identity in surprising new ways. This technology expands the possibilities for contactless sensing but also calls for careful consideration of how it affects privacy in everyday life.