Reflected smartphone transmissions enable gesture control
From: R&D Magazine - 09/22/2014

University of Washington engineers have developed a new form of low-power
wireless sensing technology that lets users “train” their smartphones to
recognize and respond to specific hand gestures near the phone.

The technology uses the phone’s wireless transmissions to sense nearby
gestures, so it works when a device is out of sight in a pocket or bag and
could easily be built into future smartphones and tablets.

Read the entire article and view a video (0:30) at:
http://www.rdmag.com/news/2014/09/reflected-smartphone-transmissions-enable-gesture-control
http://www.washington.edu/news/2014/09/19/reflected-smartphone-transmissions-enable-gesture-control/

Links:
SideSwipe: Detecting In-air Gestures Around Mobile Devices Using Actual GSM
  Signals 
http://www.keyuc.com/research/SideSwipe/SideSwipe_UIST2014.pdf

AllSee
http://www.washington.edu/news/2014/02/27/battery-free-technology-brings-gesture-recognition-to-all-devices/

WiSee
http://www.washington.edu/news/2013/06/04/wi-fi-signals-enable-gesture-recognition-throughout-entire-home/