A Novel Secure Enhancement Chaotic Communication System Based on Merging Conversion Structure for Physical-Layer Encryption

An electro-optic (EO) chaotic system with time-delay signatures (TDS) concealment based on merging conversion structure is proposed and analyzed. The proposed system can generate high-complexity chaotic signal with a relatively small feedback gain coefficient, and the TDSs are concealed effectively compared to other methods. Meanwhile, the key space of the system is enhanced by introducing more tunable time delay, which is about the order of
$10^{12} $
. Moreover, the synchronization performance of the system is analyzed. The results show that the synchronization performance is robust to the feedback gain coefficient and extremely sensitive to time delay. The proposed system can effectively resist eavesdropping and provide security for optical networks.