A new method for the realization of non-autonomous chaotic oscillators

We first present a simple circuit design method for obtaining a non-autonomous chaotic oscillator circuit from any given second-order sinusoidal oscillator with two capacitors. The proposed method relies on applying a periodic pulse train as the excitation source and an addition of signum-type nonlinear self-feedback to the given sinusoidal oscillator. The existence of chaos in the resulting system has been shown using the Poincare/spl acute/-Birkhoff theorem. Experimental results verifying the theoretical analysis for two novel chaotic oscillators are given. Secondly, we introduce a new non-autonomous system which generates a butterfly attractor similar to the one of the classical Lorenz system.