Finite Time Chaos Synchronization in Time-Delay Channel and Its Application to Satellite Image Encryption in OFDM Communication Systems

This paper proposes a finite time chaos synchronization approach for the secure communication of satellite imaging. To this end, chaotic oscillators are considered in both the transmitter and receiver ends to generate the chaotic encryption/decryption keys. To mitigate the non-negligible channel time-delay between the receiver and transmitter, we propose a robust controller design. The proposed approach is designed based on the Lyapunov stability theory and the finite-time synchronization concept to attain finite time synchronization in a time-delayed channel. By using synchronized chaotic keys, a physical-layer chaotic encryption scheme for transmitting the satellite images is designed in orthogonal frequency-division multiplexing wireless network. The proposed chaotic-based satellite image encryption/decryption system is validated using a numerical simulation study. Additionally, to analyse the robustness and demonstrate the efficiency of the proposed chaotic encryption structure, a set of security analysis tools such as histogram analysis, key space analysis, correlation test, information entropy and other statistical analysis were performed.