Voice Chaotic Secure Communications And FPGA Technical Implementation

With the continuous improvement of the chaotic theory, chaos has had wide development on the scientific, economic, engineering and philosophical realms. Especially in a direction of secure communication, the outstanding research findings are the chaotic control and the chaotic synchronization, and it has obtained the actual application in circuit,DSP and FPGA technology.But at the moment,limited by hardware performance, algorithmic complexity,communication environment and other factors,The most of the research object is static audio,image and video data. It is few to see the research of real-time data secure communication.The research object of this article is real-time data.The speech security is an important branch of information security.In order to protect the speech security,many speech encryption methods have been proposed. The chaotic encryption algorithm is relatively new, and have a good application prospects. The purpose of this paper is to promote the practical application,By building a hardware platform on FPGA, realizing the secure communications of the real-time voice. The system use xilinx’s EDK development tools and IP core provided by the existing to build the whole hardware platform. Then software programs are developed using C language including speech recorders,network communication and other software functions.In addition,The system uses the drive response type of chaos synchronization and its theory is more perfect, better synchronization performance. Finally, after the experiment test, the result shows that the system has a good real-time performance,high confidentiality and meet the requirements of applications.The main contents of this paper include:(1) Based on the SOPC technology, building the hardware and software environment in the embedded system development. To solve the problem that how to modify IP core, add IP core and configure IP core. Understanding the structure of the embedded hardware platform and handle the relations about the microprocessor, bus and peripherals. In addition, to complete the configuration of software platform, such as the configuration of lwip.(2) Realizing the acquisition and playback of voice signal. In the process of realizing the function, two problems were met:First,the IP core about audio we select will not work because of the reset question. Second, finding pause phenomenon for a short period of time in the playing process. The second problem cannot be solved, only by shortening the pause time to improve the effect.(3) The realization of chaotic encryption system. In the absence of coding, the data size of Real-time speech signals is very big, and we need a lot of chaotic sequence to realize encryption.It also brought a question that the encryption program need a longer time to run.so affecting the real-time performance of the whole system.This paper improved the encryption algorithm.By the method of a chaotic sequence for multiple audio data, achieving the goal of reducing chaotic sequence.