Imagine playing a video game like Call of Duty or Battlefield and having the ability to lead your virtual army unit while moving freely throughout your house. Gaming could become this realistic, thanks to new technology developed by Dina Katabi's research group at the MIT Computer Science and Artificial Intelligence Lab (CSAIL) that allows for highly accurate, 3-D motion tracking. The new system, dubbed "WiTrack", uses radio signals to track a person through walls and obstructions, pinpointing her 3-D location to within 10 to 20 centimeters -- about the width of an adult hand. The researchers will present their findings during the Usenix Symposium on Networked Systems Design and Implementation in April 2014. "Today, if you are playing a game with the Xbox Kinect or Nintendo Wii, you have to stand right in front of your gaming console, which limits the types of games you can play," says Katabi, a professor of computer science and engineering and co-director of the MIT Center for Wireless Networks and Mobile Computing.