Nowadays, as more and more kinds of electronic devices are booming, many applications and social software are no longer limited to one single platform. They are extended to a variety of terminals, such as smartphones, tablets and computers. However, identity authentication needs to be done repeatedly for lack of a direct means of communication, affecting users’ experience.
To solve this problem, an authentication system based on electromagnetic emanation communication, as well as the implementation methods, is proposed and designed, using smartphone as the unitary identity certification. The system consists of the server, the login terminal and a smartphone. The implementation methods include the login process, information coding protocol, means of generating electromagnetic wave on the screen and (de)modulation schemes in the smartphone receiver.
A test system is implemented in Linux system to simulate the identity authentication process. The information is transmitted without an error despite of the excessive background noise. The effective reception distance is up to 3 meters in this test, which may vary according to many factors, such as the hardware performance, reception chip in the smartphone and anti-radiation measures.
A hidden short-distance channel for information transmission is built in this identity authentication system, using electromagnetic emanation. As a result, not only the concealment of information transmission but also the convenience of login process is ensured. In the meantime, a creative angle of unitary multi-platform authentication is introduced, and it provides a great value of reference.