Researchers at the Karlsruhe Institute of Technology (KIT) have shown that ordinary Wi-Fi signals can be used to build highly detailed, camera-like images of people — even when those people aren’t carrying any connected device. Rather than relying on smartphones or special sensors, the technique analyzes the constant exchanges between standard Wi-Fi devices and translates subtle changes in radio propagation into a precise map of presence, posture and motion.

Figure 1. New WIFI Technology.

Professor Thorsten Strufe of KASTEL explains the idea this way: instead of capturing light, the system reconstructs scenes from radio waves, producing visual information comparable to a photograph. Crucially, this works whether a nearby person’s device is on or off — the method exploits the activity of other Wi-Fi hardware in the area to reveal movement and location without consent. Figure 1 shows New WIFI Technology.

Julian Todt warns that any Wi-Fi router could be repurposed for surveillance. Someone who routinely passes an establishment with an active network could be tracked and later recognized by companies or authorities without their knowledge [1]. While state actors or criminals already have simpler surveillance options (CCTV, smart doorbells), the ubiquity of wireless networks makes this radio-based imaging a potentially pervasive privacy threat.

Reference:

1. https://interestingengineering.com/innovation/wifi-tech-can-identify-individuals

Cite this article:

Keerthana S (2025), Scientists Warn: New WIFI Technology Can Identify People Without Their Devices, AnaTechMaz, pp.228