> By analyzing the exact ways that a Wi-Fi signal is altered when a human moves through it, researchers can “see” what someone writes with their finger in the air, identify a particular person by the way that they walk, and even read a person’s lips with startling accuracy—in some cases even if a router isn’t in the same room as the person performing the actions.
I'm not surprised training models on this data made the process much easier.
https://www.theatlantic.com/technology/archive/2016/08/wi-fi...