Design And Implementation Of Wireless Chaotic Voice Secure Communication System Based On ARM

Chaos is an irregular random movement that occurs in a certain system.Chaotic sequence has concealment,and is predictable in the short time but unpredictable in the long time.These characteristics make it be suitable as an encryption sequence.With the popularity of the Internet and the upgrading of network transmission rate,transmitting voice through network has become a common means of communication.But the openness of the Internet also put forward higher requirements to the security of the voice communications,and confidential information transmission is increasingly important and necessary.In recent years,with the rapid development of embedded systems,the chaotic voice secure communication system based on the embedded platform has been realized.In this thesis,the ARM platform is chosen to implement the wireless chaotic voice secure communication system in LAN,because ARM has better portability and versatility.The main contents of the thesis are as follows:Firstly,the OK6410A whose processor is ARM11 is chosen as the hardware platform.In order to develop applications on OK6410A,the cross-development environment is built,and the operating system of Linux is cross-compiled under this environment.The Qt/Embedded and Tslib are also cross-compiled in order to build the GUI development environment.Secondly,the secure communication based on chaotic synchronization is easily disturbed.While the secure communication based on chaotic coding is higher dependent on the key,and there is safety hazard in the transmission process of key.Therefore,the two methods are combined to propose a new algorithm in this thesis.After synchronization,the status value at a certain moment of the Lorenz system is used to generate the key of the encryption algorithm,and the algorithm is a stream cipher encryption algorithm based on scrambling and diffusion.The encryption algorithm is adopted to encrypt the voice information,and the statistical features of the voice are changed.The chaotic encryption algorithm proposed in this thesis improves the safety of the traditional algorithm based on a single encryption method.Thirdly,the overall scheme of chaotic voice secure communication system is designed,and the following functions are realized based on ARM:network transmission,voice gathering and playing,voice encryption and decryption,operation interface.In order to achieve the bidirectional real-time voice communication,the multi-threading mechanism is introduced.The function of system is tested,and the safety performance of the system is comprehensively analyzed.Finally,a conclusion is given,and the further research area is also proposed.