الفهرس 
Chaotic Systems Overview
Cryptanalysis of Chaotic –Based Communication SystemsOnly 14 pages are availabe for public view
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Abstract
Video transmission is required in many applications, especially in military application, such as the transmission of video from unmanned aerial vehicle (UAV) to a ground station. Since video streams are important data, so it is important to protect these data from intruders. In recent years, chaos theory has attracted much interest in the engineering community. One of the great achievements of the chaos theory is its application in secure communications.
There are many features of chaotic systems such as aperiodicity, extreme sensitivity to variation of parameters or initial conditions, and structure complexity. These features meet cryptography requirements such as diffusion, confusion, randomness and complexity of the algorithm.
In addition to chaotic-based cryptography, many techniques such as chaotic masking, chaotic shift keying (CSK) and chaotic parameter modulation are used to implement secure communication systems. These techniques have wide attention after achieving synchronization between two chaotic systems.
Recently, there are different chaotic systems have been proposed to be applicable for securing different types of data such as images, video streams and audio data. In order to obtain more complex chaotic generators for more secured schemes, hyper chaotic systems are constructed. Hyper chaotic systems have more parameters and more complex attractors than nominal chaotic systems. According to these characteristics, the design and implementation of secure communication systems to send different types of data based on hyper chaotic systems will be proposed.
In this work, two hyper chaotic systems will be investigated to be used in secure data applications, five-dimensional hyper chaotic system, and eight-dimensional hyper chaotic system. These systems are simulated and implemented to obtain the output in the form of noise-like signals and double-scroll attractors. Based on these hyper chaotic systems, the phenomenon of secure communication with chaos masking has been investigated and implemented by using field programmable gate array (FPGA) and advanced reduced instruction set computer (RISC) machine (ARM) processor. The strong effect of a very small change in the initial conditions of this system will be examined. The synchronization between two hyper chaotic systems is carried out by using a drive-response technique in which a drive signal will be sent from transmitter to achieve synchronization at the receiver chaotic generator. Based on this synchronization, two-channel communication scheme will be proposed to transmit secure information signal.
Furthermore, a new methodology is proposed for encrypting video frames based on hyper chaotic generators. This hyper chaotic generator is designed for diffusion and confusion processes required by the proposed encryption algorithm.
According to the non-linear chaotic features, the following procedures will be carried out to construct a real time video chaotic-based encryption technique. First, the hyper chaotic system is constructed, and then one of the hyper-chaotic generated signals will be used to scramble the pixel position of each video frame. Then, another hyper-chaotic signal is used for changing pixel values. A hyper chaotic–based real time secure video communication system will be designed, simulated and implemented. After that the security performance of the proposed system will be evaluated.
Due to the complexity of non-linear hyper chaotic system and the large amount of video data, the hardware implementation of such secure video transmission system is not straightforward compared with numerical simulation. In this work, a reconfigurable hardware platform is used to transmit the hyper chaotic-based encrypted video signal through wireless connection based on MyRIO platform that mainly contains FPGA and ARM processor. The selected video signal is a grayscale video signal with 30 frames per second and having a resolution of 160 x 120 pixels. A comparative study will be carried out to compare the performance of the proposed solution and other different schemes.
It can be concluded from both the numerical simulation analysis and implemented hardware results that the proposed scheme validates the good performance and feasibility of the secure data or video transmissions in wireless networks.