Network transmission of hidden data using smartphones based on compromising emanations

In this paper, we proposes a method to obtain the stored in the air-gapped computer with the help of nearby smartphones by intentionally generating loud physical emanations. We can construct a big transmission network connecting a computer and many cell phones by using different kinds of physical emanations. We further demonstrate the scenario by implementing a system using electromagnetic waves and acoustical signals. In this system, convert transmission channels are established between the computer and the cell phones. The microphone and FM receiver of the mobile phone are used to obtain the information. This kind of hidden data transmission method has the characteristics of strong concealment.