When a Wi-Fi router sends a signal to a device like a smartphone or laptop, that signal’s radio waves pass through other objects on the way. The objects absorb some of that wave, resulting in ...

A few weeks back, we reported on a research group that figured out how to measure heartrate using perturbations in WiFi signals. [Nick Bild] was interested in this so-called “Pulse-Fi” technique, but ...

Thanks to the proliferation of smartwatches and fitness trackers, it’s never been easier to log your heart rate while running: Simply don the device, start your workout, and watch those beats per ...