Chaos based true random number generator design and video encryption application in FPGA environment

With the rapid development of communication technologies in recent years, information security has become critical for everyone. Being able to guarantee the security of this information, which should be private and confidential in connection with its importance, has become a basic research question. However, it is a very difficult process to guarantee information security. In recent years, researchers have obtained new findings by examining the fractional computing approach, which has increased usability and applicability in all engineering fields, especially on signal processing, control and chaotic dynamics. The aim of this thesis is to encrypt the real-time video data by performing the chaotic system-based true random number generator design available in the literature using the fractional order calculation approach. Within the framework of the project, besides the integer-order chaotic circuit, the electronic circuit design of the fractional-order chaotic system is also used. Thus, a unique entropy source is proposed by operating both continuous time chaotic circuits and discrete time chaotic map systems designed with electronic circuit elements in switched mode together. In this thesis, both continuous-time fractional-order and discrete-time chaotic systems, which are designed with electronic circuit elements, are realised by providing a switching structure with the best statistical randomness properties, and a prototype circuit is realized. Then, the cryptographic key bits obtained at the output of the prototype circuit are post-processed with the image bits of the real-time video display system running on the FPGA hardware platform, providing encryption and displayed on the VGA monitor. In the thesis, we have two data for real-time video encryption. The first of these is the digital real random bit sequence we obtained from four different chaotic systems, and the other is the color video data given as input from the camera module to the FPGA card. Chaotic systems used as entropy sources are respectively; The discrete-time Logistics and Tent Map are continuous-time full-order Lorenz and fractional-order Chen-Lee systems. For encryption, the XOR function, which is one of the basic post-processing algorithms, is used. In the analysis phase of the thesis, statistical tests were applied for the video image data and histogram and correlation analyzes were used. In the light of the results obtained, it has been shown that the methods of the thesis study can be used in secure communication systems, especially in the fields of video communication.