1976, the famous biologist may put forward the Logistic mathematical model 14 in the article "Simple mathematical model can lead to very complex dynamic characteristics". Logistic mapping has been widely used in various chaotic encryption systems? 15 18 19 。 After that, many discrete chaotic systems have been put forward, and people are familiar with tent mapping, cube mapping and so on. 16 17. With the deepening of the research on discrete chaotic systems, it is found that there are many shortcomings in the dynamic characteristics of discrete chaotic systems, such as fixed full mapping range and small full mapping parameter interval. The research direction gradually turned to improving discrete chaotic systems. The research on the improvement of discrete chaotic systems is mostly aimed at the size of its full mapping range of 26, while the research on the expansion of the full mapping parameter range is less. 20 1 1 published a paper, the main content is how to improve the full mapping range of Logistic mapping. Applying the improved chaotic system to chaotic encryption can increase the key parameters of the whole encryption system and improve the security performance of the system. The solution of the problem of fixed total mapping interval and small total mapping parameter interval makes discrete chaotic systems better applied to the field of information security. After entering the 2 1 century, with the rapid development of various scientific disciplines, the study of chaotic systems has also entered a stage of rapid development, especially in information security and information encryption. Because of the special properties of chaotic system, such as sensitivity, convenience and unpredictability to the initial value, the digital sequence generated by chaotic system has natural advantages in encryption and confidentiality. The study of chaotic system began to gradually transform from pure theoretical research to practical application research using theory. Communication directions include secure communication, spread spectrum communication control direction, control system and optimization, and there are also many research directions combining chaotic systems. In these research directions? The research direction of chaotic secure communication is closely combined with the design of new chaotic systems, nonlinear circuits and intelligent information processing, which has a relatively rapid development prospect and will have more research space in future scientific research.