A cryptography algorithm for transmitting multimedia data using quadruple-state CSK

A new technique for secure communication is introduced that aims at robustifying classical Chaotic Shift Keying (CSK) methods. The secret data are hidden within the chaotic transmitter states that can change among four different chaotic attractors such that binary information is effectively diffused. A novel cryptography algorithm is used to change the transmitter parameters such that they have a quadruple form; thus, breaking into the public communication channel using return map attacks will fail. At the receiver side, an adaptive control method is used to estimate the time-varying transmitter parameters via adopting a complete synchronization approach. Simulation results demonstrate the superior performance of the proposed technique in both time and frequency domains. A Duffing oscillator is used to build the proposed system using only the time series for the output. Different implementation issues are investigated for various digital multimedia data and an experimental investigation is carried out to verify the effectiveness of the proposed technique. Finally, generalizations to other chaotic systems as well as real-time compatibility of the design are discussed.