Novel Four-dimensional Chaotic Oscillator for Sub-1GHz Chaos-Based Communication Systems

A simple four-dimensional chaotic circuit based on Colpitts configuration is presented, it generates chaotic oscillations at Sub-1GHz frequencies with almost flat spectrum. The chaotic dynamics are illustrated by waveforms of the signals, bifurcation diagrams, phase portraits of the attractors and spectra of the oscillations, using both numerical and circuit simulation. The Circuit simulation is carried out using Advanced Design System (ADS) tool, with the PSpice model of the used transistor to support the theoretical analyses. The spectral characteristic of the proposed generator makes it promising for many communication applications such as spread spectrum communication, direct chaotic communication and so on.