This paper explores the performance of a single input multiple output (SIMO) free space optical (FSO) communication system using differential chaos shift keying (DCSK) with diversity combining techniques. Specifically, presents use maximal ratio (MRC), equal gain (EGC), and selection (SC) techniques for DCSK-FSO system. Adding to FSO systems can significantly improve reliability performance, ma...

Abstract Motivated by today’s huge volume of data that needs to be handled in secrecy, there is a wish develop not only fast and light but also reliably secure cryptosystems. Chaos allows for the creation pseudo-random numbers (PRNs) low-dimensional transformations need applied small number times. These two properties may translate into chaos-based cryptosystem both (short running time) (little...

As any well-designed information security application uses a very large quantity of good pseudorandom numbers, inefficient generation of these numbers can be a significant bottleneck in various situations. In previous research works, a technique that applies welldefined discrete iterations, satisfying the reputed Devaney’s definition of chaos, has been developed. It has been proven that the gen...

In this paper, psuedo random binary sequences are generated from the “Chaos Based Key Stream Generator- using novel Permutation technique with two dimensional patterns and substitution Z4 mapping” investigation of auto correlation property for seuwnces is presented. Initially a chaotic function, considering Logistic map used to generate Pseudo Random Numbers (PRNs). Then these numbers converted...

Road traffic volumes in intercity roads are generally estimated by probability functions, statistical techniques or meta-heuristic approaches such as artificial neural networks. As the road traffic volumes depend on input variables and mainly road geometrical design, weather conditions, day or night time, weekend or national holidays and so on, these are also estimated by pattern recognition te...

We report some experiments undertaken to investigate the origin of ordered and chaotic laminar vortex streets behind circular cylinders at low Reynolds numbers. We made simultaneous measurements of near wake longitudinal velocity and cylinder lateral vibration amplitude spectra for cylinder Reynolds numbers in the range from 40 to 160. For a non-vibrating cylinder the velocity energy spectra co...

In this paper, we demonstrate the current limitations of quantifying chaos using floating-point numbers at finite time. Alternatively, we introduce a stable method for quantifying chaos of a given dynamical system using rational numbers at finite resolution. The proposed method is based on constructing a combinatorial representation of a given dynamical system, expressing it as a graph, perform...

In order to achieve chaotic signal processing, a dedicated chaos processor is required. The chaos processor is composed of two parts: chaos signal generation and chaos signal retrieval (Fig. 1). Chaos signal generation is used to generate chaos signal, while chaos signal retrieval is used to retrieve initial state of received chaos signal. Since chaos signal is analog in nature, with convention...

In this paper we study the link between ‘turbulence strength’ in a flow and the leading Lyaponuv exponent that characterize it. To this end we use two approaches. The first, analytical, considers the truncated convection equations in 2-dimensions with three (Lorenz model) and six components and study their leading Lyaponuv exponent as a function of the Rayleigh number. For the second approach w...

Accurate detection of weak periodic signals within noise and possibility of secure messaging have made Duffing oscillator (DO) highly important in the field of communication. Investigation on the properties of DO is thus ardently sought for. An elegant approach to accomplish the same is to fabricate electronic circuit simulating DO non-linear equation and to study the effect of input signal amp...