According to Strategy Analytics, about 690 million households have broadband Internet service worldwide. Of these, nearly two thirds — more than 450 million — have WiFi wireless networking. One company hopes to capitalize on this market penetration by using those WiFi signals for a new purpose.

One of the solutions to help the elderly live independently in their own homes is to install sensor networks that detect the motions of people in the rooms. Using infrared or radio spectrum transmitters and receivers, these devices can sense when someone is moving. Aerial hopes to eliminate those transmitters, and rely simply on the presence of WiFi transmissions. The radio waves used for WiFi are reflected by objects in a space, such as walls, furniture, and people. As a result, the path taken by WiFi signals varies depending on the position of the obstacles. If an obstacle is moving — such as a person — the position of that object can be inferred by changes in the WiFi signal paths. Note that this system does not rely on the content of the WiFi signals; it simply observes how the waves propagate within the space and tracks the changes. As a result, a passive sensor network can be created quickly and easily. The receivers could be incorporated into a simple device that plugs into a standard household power outlet. And since WiFi signals travel through most walls, you would not need a sensor in every room to provide effective coverage.

This system could monitor the activities of seniors living on their own, or could provide fall detection, or could even be a security system to detect intruders. The company is looking to license its technology to broadband service providers and equipment manufacturers, and plans to have a developer kit ready in early 2016.