Design And Realization Of Digital Chaos Encryption System Based On DSP

This paper discusses the method of design and realization of digital chaos encryption system based on DSP. And then, the paper specifies algorithm design, hardware design and software design for this system in detail.This paper presents theory of chaos and chaotic system at first, and then analyses chaos encryption techniques and some applications in the field of image encryption. After choosing Logistic map as the starting point of research, this paper analyses its encryption characteristic and points out its security problem as a common chaos system. The application of hyperchaos is one of research emphases of present encryption technology. In order to design chaotic encryption algorithm with good security, this paper analyses encryption effect of hyperhenon map for digital image encryption and narrates the problem for hyperchaos system when used in image encryption. Based on above analysis, this paper proposes a new mixed encryption algorithm improved to attain good security. According to the real encryption result, this algorithm has outstanding advantages such as great secret key room, highly complexity signal and good random property, which is suitable for applying on the platform of hardware.Design of hardware is the critical section of this paper. Firstly, it discusses DSP technology and some applications. And then based on the structure and character of TMS320VC5416, this paper discusses the digital image encryption system. The system consists of four parts: DSP hardware circuit, interface circuit of USB, interface circuit of FLASH and power circuit. This paper presents their design ideas, circuit principles and chip structures. Just as USB2.0 protocol is the basis of USB circuit design, PCB is the critical point of the whole system. And this paper discusses all of them in detail.After having realized the hardware circuit, this paper discusses software design of digital chaos encryption system in detail. Software design in this system can be divided into DSP program, USB driver program and application program. This paper introduces the development of DSP program, function and flow charts of the program. For driver, the difficulty in the development of USB device, this paper presents its function and methods of development, and gives main design idea. As the primary interface implementing the user's order, HOST program is also discussed briefly in the end.