Wireless is ubiquitous and playing increasingly important roles in our everyday lives. While wireless data communication has achieved a great success, a lot of new applications were proposed in the last few years hosted on Wi-Fi and RFID infrastructures including indoor localization, gesture recognition, respiration sensing and even material identification. Several systems will be introduced in this talk. The first, ArrayTrack (NSDI ’13), is an indoor localization system hosted on Wi-Fi infrastructureto achieve​ an accuracy below 50 cm. ToneTrack (MobiCom ’15) is another Wi-Fi based system which breaks the bandwidth limit for time-based localization. TagScan (MobiCom ’17) is able to differentiate very similar liquids such as Pepsi and Coke with just commodity RFID device while the last system Restrack (UbiComp ’18) is not only able to monitor subtle human respiration accurately without any device attached to the target but also explains the deep reason why some locations have inherently better respiration sensing capability than other locations.

​

​

​