Design Of Memristor-based Chaotic System And Application Of Image Encryption

The memristor concept was first proposed in 1971 and a mockup was made in2008.Memristor is a basic component of nonlinear circuit with nanometer size.It has the advantages of small size,fast speed,low power consumption and high integration.The discovery of memristor opens up a new way for the research and development of electronic engineering,secure communication,chaotic circuit,artificial neural network and other engineering applications.Power system transmission and distribution network is an important national facility.With the continuous progress of science and technology,the power system is gradually developing towards the direction of intelligence.Autonomous inspection of transmission lines by UAV replaces traditional manual inspection,which not only ensures personal safety but also shortens the inspection period.However,the data such as pictures may be subject to risks such as theft,tampering and attack during transmission.Therefore,it is of great significance to encrypt the transmitted picture data.Based on this background,two memristor chaotic systems are constructed in this paper,and the two systems are simulated and analyzed respectively.Based on the two systems,two image encryption algorithms are designed.The specific work is summarized as follows:(1)Two memristor chaotic systems based on cubic nonlinear magneto-controlled memristor are constructed.Firstly,the voltammetry characteristic curve of the selected magneto-controlled memristor is studied by experiments.Secondly,a four-dimensional memristor chaotic system and a five-dimensional memristor chaotic system are constructed based on the memristor.The two systems are studied by means of bifurcation diagram,Lyapunov exponential spectrum and Poincaré mapping.It is found that the four-dimensional memristor chaotic system has a line equilibrium point,and the attractor type is highly dependent on the internal parameters of the memristor and the memristor strength.Five-dimensional memristor chaotic systems exist extremely multistability which depends on the change of memristor initial conditions.The analysis shows that both systems have complex dynamic behavior.(2)Two memristor chaotic systems are simulated and implemented.The modular circuit of the four-dimensional memristor chaotic system is designed on the Multisim platform.The simulation and debugging are carried out according to the constructed circuit.The experimental results are consistent with the simulation results,which verifies the correctness of the system.Based on field programmable gate array(FPGA)technology,the digital circuit of the five-dimensional memristor chaotic system is realized.The phase diagram captured on the oscilloscope is consistent with the numerical simulation,which verifies the realization of the system.(3)Based on the constructed two memristor chaotic systems,two image encryption algorithms are designed.Firstly,an image encryption algorithm based on four-dimensional memristor chaotic system,dynamic DNA coding technology and compressed sensing technology is designed,and a pseudo-random sequence based on key stream generation mechanism is proposed.This mechanism is very sensitive to pure image and four-dimensional memristor chaotic systems.Secondly,an image encryption algorithm based on five-dimensional one-group chaotic system and compressed sensing technology is designed.The image signals are sparse by using DCT transform,the measurement matrix is constructed by using chaotic system,and the measured values are used for encryption.Finally,the security analysis shows that the two encryption schemes have good encryption effect and are suitable for the power system image data encryption.