If you have been greedy by TSA, please raise your hand. The research team insists that normal Wi – Fi can detect weapons and explosives.
The team behind the study tested 15 kinds of objects and 6 kinds of bags. The wi-fi system had a success rate of 99% for recognizing hazardous materials, 98% of metals, 95% of liquid. When the object was wrapped in a bag, the accuracy dropped to about 90%. This system works by analyzing what happens when radio signals penetrate objects and materials and bounce back.
check it out: Perhaps Wi-Fi could replace invasive TSA body search