Research And Circuit Design Of Arctangent Transformation Based On Chua Chaos

The chaotic system has intrinsic randomness,and the sequence generated in the chaotic state has similar characteristics to the random signal.Therefore,it is very suitable for use as a key sequence generator in an encryption system.However,with the advancement of deciphering technology,it is difficult for the low-dimensional chaotic system used for encryption to resist deciphering attacks.High-dimensional chaotic sequence has high randomness and irregularity,but its research is difficult.How to improve the chaotic characteristics of existing chaotic systems through a method to generate chaotic sequences with better randomness and complexity? About this problem,the paper proposes a method of chaotic arctangent transformation,through the arctangent transformation of the Chua chaotic sequence,to achieve the purpose of enhancing the randomness and complexity of the sequence.In order to obtain uniformly distributed chaotic sequences,based on the Chua chaotic system,this paper conducts the research of statistical distribution,information entropy and Lyapunov characteristic exponent on the Chua chaotic sequences generated before and after transformation,and makes a lot of MATLAB simulations experiment.After Chua chaotic sequence undergoes arctangent transformation,its distribution characteristics become more uniform,and the information entropy reaches 7.212,which is close to the theoretical maximum value of 7.228.Its complexity has increased,and the Lyapunov characteristic exponent has increased by 0.625.This verifies the feasibility and effectiveness of the chaotic arctangent transformation.Finally,the method of comparison and experimental reasoning is used to screen out the optimal arctangent transformation form,and the realization method of the chaotic arctangent transformation circuit is studied.Through comparative analysis of Taylor algorithm and CORDIC algorithm,the CORDIC algorithm has a small absolute error,fewer hardware resources consumption,high precision and simple implementation.Therefore,according to the CORDIC algorithm,the hardware system of the chaotic arctangent transformation circuit is designed using FPGA,and the function of the circuit is tested.The test results verify the successful realization of the circuit design.