A Secure Communications System Using Chaotic Switching

Abstract

Since previous secure communications methods using chaotic systems require very high SNRs, knowledge of the initial conditions, and/or chaotic systems with the self-synchronization property, their application is limited. In this paper, a new secure communications scheme based on chaotic switching is discussed. The proposed scheme makes decisions on the incoming bits by comparing the power level of the dynamical error for each symbol signal after applying a noise reduction method based on the known system dynamics. A multi-user secure communications scheme is also considered where each user's symbol signal is mapped through a unique scramble matrix. We also examine whether these scramble matrices help to combat against smart jamming. The proposed system does not require self-synchronization between the chaotic receiver and transmitter and exhibits reasonable performance at relatively low SNRs.