Detecting presence without cameras or badges: WiFi waves as a sensor

What if your presence could be detected… without a camera, without a badge, without you even knowing? This is not science fiction.

Today, certain technologies can analyse disturbances in WiFi signals to detect presence, movement, or estimate the number of people in a space. The principle is simple: the human body alters how WiFi waves propagate, and these variations can be exploited to turn an environment into a sensor.

Beware of the myths, however:

• no, you cannot “precisely spy on your neighbour” with an ordinary home router;
• no, this is not easily accessible without technical skills;
• but yes, these technologies genuinely exist and are gradually becoming more accessible.

And that is where the real questions begin. Where does detection end, and where does surveillance begin? How do we govern these uses in compliance with the GDPR? How far are we willing to accept these invisible technologies?

In professional contexts - monitoring, security, crisis management - they can bring real value: responsive systems, intelligent automation, better operational efficiency. But like any powerful innovation, they must be used responsibly.

Technology moves fast. The framework around it must keep up.

Patrice Barrault, co-founder and technical director of Easy Multi Display