American researchers at the University of California have developed a new system called “Pulse-Fi” that uses home Wi-Fi signals to accurately measure heart rate without the need for a smartwatch, chest strap, or hospital monitoring device.

Nayan Bhatia, the lead researcher, explained: “The new technology works by analyzing the behavior of radio frequency waves as they travel through space. When Wi-Fi signals hit the human body, they are partially absorbed and scattered.”

He added, “Heartbeats slightly but detectably affect the behavior of wireless frequency waves, and by applying advanced machine learning algorithms, the system can isolate these changes from surrounding noise such as movement or environmental interference.”

Tests on 118 participants showed the system can measure heart rate with an error margin of no more than half a beat per minute, after only five seconds of signal analysis. The technology maintained its accuracy whether the user was sitting, standing, or even walking, and it can operate from a distance of up to three meters without performance degradation.

Researchers hope to expand the system’s use to monitor breathing rate, which could help diagnose respiratory diseases such as sleep apnea in the future.