Research On Improved Chaotic System And Its Circuit Realization

Since Lorenz found chaotic motion, chaotic theory has received widely attention.Chaotic signal, because of its pseudo randomicity, ergodicity, continuous broadband frequency spectrum characteristics and similarity of noise, has alreay been widely used in secret communication, waveform cover, the application of image encryption and some other fields. In this paper, we make a preliminary research of the chaos theory.We design and realize new equations of chaotic signal and also make a digital and analog hybrid system which based on chaotic signal to generate a random sequence.This article first introduces and analyzes the basic theory of chaos which from multiple perspectives of dynamic chaotic characteristics, and sets out some classical chaotic systems. Secondly we puts forward a idea, which adds a nonlinear term to the original systems.We analyze the new systems by the bifurcation diagram, Lyapunov index and chaotic attractorsand and some other dynamics characteristics of chaos, and found that the amplitude and frequency of the new system can be controled. Then we use two ways including analog and digital circuit to achieve the chaos equations. The analog way is based on the simulation of Multisim and the actual construction of the concrete circuit, while the digital way depends on the FPGA programming and hardware board debugging. Both modes ultimately successful display waveform and we make a comparative analysis. Finally we proposed a mixed system, which is a practical application of the chaotic signal, to produce random sequence. Through Matlab simulation and actual circuit build, a random sequence can be successful produced by this system which can pass the Nist testing standard. We verify that the whole system is a kind of high speed and reliable random sequence generator.