Security-enhanced electro-optic chaotic communication system based on the logistic map feedback and dynamic key

Abstract

In this paper, a novel electro-optic chaotic system based on the logistic map feedback (EOLM) is proposed. The logistic map is used to introduce additional nonlinear effects into the electro-optic feedback loop. The simulation results show that, with the increase of logistic map iterations N, the bandwidth and permutation entropy of the chaotic output can be significantly increased, and the spectrum is flatter. The time-delay signature (TDS) of the system can be concealed within the appropriate range of values of parameters, which ensures the security of the key. Synchronization results show that the system is not only sensitive to time delay T but is also sensitive to the feedback intensity β, so β is also the key of the system. Utilizing the sensitivity to β, a dynamic EOLM communication system with changing key (DEOLM) is designed. Based on chaotic self-control, the chaotic optical signal is transformed nonlinearly to generate the control signal, which drives the gain coefficient of the amplifier to change dynamically, so as to realize the changing of β. Simulation of communication performance shows that the DEOLM system greatly raises the difficulty for the eavesdropper to crack the message and improves the confidentiality of communication.