The Realization Of The Secondary Secure Communication Based On Fractional And Integer Order Chaotic Circuit Systems

Chaotic circuit theory is an important branch of the modern non-linear science,which has fatal research significance. This research focused on three areas. First, we discuss the effects of chaos indicators on dissipative systems, those indicators are widely used in conservative systems. Second, the dynamic behavior of a new four-dimensional fractional order and a five-dimensional hyper-chaotic system are investigated. Finally, in view of the two chaos systems, we design the level 1 and level 2 secret communication circuits.So far, bifurcation diagram and lyapunov exponent spectrum have been used to determine the dynamic behavior of the system in dissipative systems. In this paper,first we analyze whether the chaotic indicators widely used in conservative system can be applied in dissipative system. Because of lacking theoretical analysis, we can only use large sample simulation experiment to verify the role of chaos indicators in the dissipative system. Numerical simulation shows that the lyapunov exponent, fast lyapunov indicator, relative finite-time Lyapunov indicator and smaller alignment index can be applied to the dissipative system. On the basis of the chaotic indicators,we design a new four-dimensional fractional order chaotic system and a new five dimensional hyper-chaotic system. The stability of the libration point and the phase volume are discussed. According to Liouville’s theories, we find that the two systems are dissipative. By means of using the improved method of modular design, we have finished their circuit experiment. It shows that the oscilloscope observations are accordance with numerical simulation results. Consequently, the new system has complex dynamic behaviors. Secondly, in circuit applications, the drive-response synchronization and feed back-drive response are used to realize the chaos synchronization of two systems. Meanwhile, the Level 2 encryption is realized by the feed back-drive response and chaos masking. What’s more, the signal can be decrypted step by step and the numerical modeling results are given. At last, the influence of the chaotic synchronization on the error is discussed. By using chaotic scrambling method and digital image processing digital before chaos masking encryption respectively, we give numerical simulations to the image transmission of secret communication. Comparing the results, we find that the effect of the second method is better at the signal reduction degree. It can satisfy the demands in practical engineering.This article has three aspects of significance: first of all, we point out that chaos indicators used for conservative system can still be applied to the higher dimensional dissipative system. Second, in order to realize secret communication, we have built the new fractional order chaotic and high dimension hyper-chaotic circuit model, and designed the corresponding lever 1 secret communication circuit. Finally, both lever 1and level 2 secret communication circuits of the two models are realized.