Chaotic Encryption System Design Based On Nonlinear Feedback Synchronization And FPGA Implementatio

The advent of the large data era is accompanied by an increase in the amount of information interaction,and at the same time,the information security problem is gradually revealed,and how to ensure the security of information becomes a key issue in information development.Chaos has an important application in the field of information security because of its high sensitivity and randomness,and chaos control provides an effective method to control the state of chaotic systems,which further improves the reliability and security of chaos in practical applications.As an important research direction in chaotic control,chaos synchronization can synchronize the states of multiple chaotic systems,which is very suitable for confidential communication and secure data transmission.The key sharing and synchronization is achieved by synchronizing and controlling the chaotic systems of the sender and the receiver to encrypt and decrypt the communication data and provide higher security.In this paper,a nonlinear feedback synchronization control method was designed to realize chaos synchronization on the foundation of the proposed new 5-D hyperchaotic system.Based on the proposed method,an image encryption system has been designed and implemented on FPGA.In this paper,a new 5-D hyperchaotic system was proposed.Its dynamics have been analyzed by Matlab simulation.The results have shown that the proposed system had good performance.The overall design of the digitalization of the new 5-D hyperchaotic system was implemented on FPGA.The continuous chaotic system has been discretized by Euler method and proportional compression operations.An integration of combinational and timing logic has been used to balance the operation speed and resource consumption of the circuit.The RTL-level simulation has been used to verify the function of the module.This paper has also proposed a nonlinear feedback synchronization control method and implemented it on FPGA.By introducing three nonlinear terms in the control term,two 5-D hyperchaotic systems have been synchronized with fast and high accuracy at different initial values.Furthermore,a brief analysis of the synchronization establishment time and synchronization accuracy has been conducted.The feasibility of the FPGA implementation of the nonlinear feedback synchronization control method has been verified,and the foundation was laid to ensure the application of the FPGA-based nonlinear feedback synchronization control method to confidential communication systems.This paper has sampled and reconstructed the generated chaotic sequence with the help of 5th order m-sequence to generate a new combinatorial chaotic pseudo-random sequence.The test results have shown that the generated combinatorial chaotic pseudorandom sequence performed better than the original sequence.Finally,all the modules have been integrated to complete the design of initial key reception,combined chaotic pseudo-random sequence generator,HDMI output display,key sending and receiving control,and image encryption and decryption,etc.A nonlinear feedback synchronous chaotic encryption system has been realized based on FPGA.