Technology that uses radio waves can observe people’s movements through walls, and it may become the future of health care and smart houses, according to researchers.
Computer scientists at the Massachusetts Institute of Technology (MIT) in Cambridge, Massachusetts created a system that can generate radio waves that bounce off people’s bodies. The reflections are then picked up by receivers, and are processed by computer algorithms that map real-time movements of people.
The new device is different from other motion-tracking devices because it uses radio signals with short wavelengths that are able to go through walls. Researchers call the new system RF-Capture; it managed to identify fifteen people through a wall with approximately 90 percent accuracy.
The technology may someday be used to monitor the vital signs of hospital patients, or in gaming devices that are controlled by gestures.
Fadel Adib, lead author of a new paper and a Ph.D. student at the Computer Science and Artificial Intelligence Lab at Massachusetts Institute of Technology, said that over the last three years he and his colleagues made a lot of progress from a device that cold only sense coarse movement behind a wall, to one that is practically able to see roughly what the person looks like, and even measure the heart rate and breathing of a person.
Dina Katabi, a professor of electrical engineering and computer science at MIT, has been working on wireless tracking technologies for some years now.
The new system uses radio waves that are about 1,000 times less powerful than regular Wi-FI signals. According to Adib, RF-Capture also has better software and hardware, making it a far more effective device.
The device looks like a T-shaped antenna that has sixteen receivers on its horizontal section and four transmitters on its vertical section. RF-Capture is controlled from a regular computer using a powerful graphics card, the researchers said.
The system can identify which body part a person has moved from approximately 10 feet (three metres) away through a wall, with 99 percent accuracy.
According to researchers at MIT, the system only costs $200 to $300 to build. The team wants to use the new technology in a product called Emeralds, which predicts and prevents falls among seniors.
The new system was presented at the Special Interest Group on GRAPHics and Interactive Techniques (SIGGRAPH) Asia conference held from November 2 to November 5 in Japan.