Ihsan Pehlivan

Nonlinear Sprott94 Case A chaotic equation: Synchronization and masking communication applications

The nonlinear autonomous Sprott94 Case A chaotic equations are algebraically simple but can generate a complex chaotic attractor. In this paper, the Sprott94 Case A system is found suitable for chaotic synchronization circuits and chaotic masking communication circuits using Matlab-Simulink(R) and Orcad-PSpice(R) programs. Simulation results are used to visualize and illustrate the effectiveness of Sprott94 Case A chaotic system in synchronization and secure communication. The applicability of chaos to secure communication is verified by all simulation results performed on Sprott94 Case A chaotic system.

Simplified chaotic diffusionless Lorentz attractor and its application to secure communication systems

Diffusionless Lorentz equations a simplified one-parameter version of the well-known Lorentz model. Also, it was attained in the limit of high Rayleigh and Prandtl numbers, physically corresponding to diffusionless convection. A simplified, one-parameter version of the Lorentz model called diffusionless Lorentz is proposed, which is suitable for chaotic synchronisation and masking communication circuits using Matlab–Simulink and PSpice programmes. It is also suitable for a real electronic experimental circuit.

SIMULATION AND CIRCUIT IMPLEMENTATION OF SPROTT CASE H CHAOTIC SYSTEM AND ITS SYNCHRONIZATION APPLICATION FOR SECURE COMMUNICATION SYSTEMS

Nowadays, many simulations, implementations, synchronization and secure communication applications of chaotic circuits have been introduced in literature. However, electronics circuit design and im...

A new three-dimensional chaotic system without equilibrium points, its dynamical analyses and electronic circuit application

Original scientific paper In this paper, a new three-dimensional chaotic system without equilibrium points is introduced and analysed. Basic dynamical analysis of this new chaotic system without equilibrium points is carried out by means of system equilibria, phase portraits, sensitivity to initial conditions, fractal dimension and chaotic behaviours. In addition, in this paper Lyapunov exponents spectrum and bifurcation analysis of the proposed chaotic system have been executed by means of selected parameters. The chaotic system without equilibrium points has been executed by detailed theoretical analysis as well as simulations with designed electronical circuit. A chaotic system without equilibrium points is also known as chaotic system with hidden attractor and there are very few researches in the literature. Since they cannot have homoclinic and heteroclinic orbits, Shilnikov method cannot be applied to find whether the system is chaotic or not. Therefore, it can be useful in many engineering applications, especially in chaos based cryptology and coding information. Furthermore, introduced chaotic system without equilibrium points in this paper can have many unknown dynamical behaviours. These behaviours of the strange chaotic attractors deserve further investigation.

A new 3D chaotic system with golden proportion equilibria: Analysis and electronic circuit realization

This article introduces a new three-dimensional quadratic continuous autonomous chaotic system with golden proportion equilibria, which can generate single folded attractor. Some basic dynamical behaviors and the dynamical structure of the new chaotic system are investigated either analytically or numerically. Finally, the chaos generator of the new chaotic system was designed, simulated and experimentally confirmed via a novel electronic circuit design. A good qualitative agreement is illustrated between the simulations and the experimental results. It is convenient to use the new system to purposefully generate chaos in chaos applications. The new system has eight terms, two quadratic nonlinearities and two parameters (a and b). The new chaotic attractor equations have three equilibrium points and more interestingly the equilibrium points have golden proportion values.

Amplitude Control Analysis of a Four-Wing Chaotic Attractor, its Electronic Circuit Designs and Microcontroller-Based Random Number Generator

An exhaustive analysis of a four-wing chaotic system is presented in this paper. It is proved that the evolution range of some variables can be modulated easily by one coefficient of a cross product term. An amplitude-adjustable chaotic circuit is designed, which shows a good agreement with the theoretical analysis. Also, in this paper a microcontroller-based random number generator (RNG) was designed with a nonlinear four-wing chaotic system. RNG studies of the current time have been usually carried out with complicated structures that are costly and difficult to use in real time implementations and that require so much energy consumption. On the other hand, in this paper, as opposed to the disadvantages mentioned here, a microcontroller-based RNG was designed with a four-wing chaotic system (also discussed in the paper) and this was introduced to literature. Microcontroller-based random numbers that passed randomness tests will be available for use in many fields in real life, particularly in encryption.

Text encryption by using one-dimensional chaos generators and nonlinear equations

In this study, a chaos based encryption method with nonlinear equations in MATLAB environment is proposed to increase communication security. Encryption methods that generated by using the properties of three different chaos generators are analyzed. Logistic Map, Pinchers Map and Sine-Circle Map chaos generators which are commonly referred in the literature are used to realize applications. Performance is analyzed by using time and entropy values.

Design and implementation of chaos based true random number generator on FPGA

Currently, chaotic signal generators is of importance in cryptographic applications and chaotic communication systems. One of the significant field of the chaotic signal oscillators are random number generators. In this paper, an FPGA-based new true random number generator system using discrete-time chaotic signal generator is presented. The system designed incorporates the Sprott 94 G chaotic system based on an FPGA deployed with IEEE 754 standard. In order to produce random bits a quantification process has been performed on the results produced by the chaotic oscillator unit. Furthermore, the XOR method has been determined as restoring function to obtain a true random bit generator. The maximum operating frequency of FPGA-based true random number generator has been able to reach up to 399,383 MHz. The 20,000-bit sequence has been generated by the designed system and they have been saved to the test result file. They have been tested using NIST test suite and FIPS-140-1 standards and successful results have been obtained. It is concluded that the FPGA-based system is able to be used in cryptologic applications.

Real time implementation of a novel chaotic generator on FPGA

In this study, a new continuous-time autonomous chaotic system has been presented and implemented on FPGA. Presented a new chaotic system has been designed using the IEEE 754-1985 floating-point format and implemented using Heun algorithm with VHDL language. The designed system has been synthesized and tested on Xilinx Virtex-6 FPGA chip. According to the test results, operation frequency of the FPGA-based a new chaotic signal generator is certain as 390 MHz and performance results have been given with chip statistics. In addition, the results obtained from FPGA-based new chaotic generator have been compared with the Matlab-based numerical results and it has been observed that obtained results are successful. By the developed FPGA-based novel chaotic system model, chaos-based various engineering applications such as true random number generation and secure communication system can be performed.

Chaos-based encryption of multimedia data and design of security analysis interface as an educational tool

Data encryption has always been a topical subject. There are many encryption methods in the literature. Chaos‐based encryption is considered a different area of study among the encryption practices. In this study, a novel interface was designed for chaos‐based encryption to be used as an educational tool in cryptology. With this interface, the chaos‐based encryption of multimedia data (picture, audio, text) can be done with one, two, or three dimensional discrete‐time chaotic maps. Also, the reliability of every encryption method must be checked via certain security analyses. Thus, five different security analyses (information entropy, correlation, speed effect, differential attack, and histogram analysis), where applicable, were added into the interface to perform security analyses of chaos‐based encrypted data. In this way, the chaotic encryption and security analyses, both of which need high level programming knowledge, have become available in a compact way, for those who are interested in this subject but are not knowledgeable enough about programming, hence the interface can be used as an educational tool in chaos or encryption studies.