Image: Man Zhou, Qian Wang, Kui Ren, Dimitrios Koutsonikolas, Lu Su, Yanjiao Chen
Researchers in China and the U.S. have created a system for receiving hidden data in audio signals using smartphone microphones. The Dolphin system uses commercial off the shelf (COTS) smartphones to detect, error correct and decode hidden data transmitted in audio within an 8 meter distance and up to an angle of 90 degrees. Transmission of sport stats data via stadium speakers without the need for internet connectivity is one possible implementation of this mass transmission system.
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