Nonlinear observer control for full-state projective synchronization in chaotic continuous-time systems

Projective synchronization, characterized by a scaling factor that two coupled systems synchronize proportionally, is usually observable in a class of nonlinear dynamical systems with partial-linearity. We show that, by using an observer-based control, the synchronization could be realized in a general class of chaotic systems regardless of partial-linearity. In addition, this technique overcomes some limitations in previous work, capable to achieve a full-state synchronization with a specified scaling factor, and adjust the scaling factor arbitrarily in due course of control without degrading the controllability. Feasibility of the technique is illustrated for a chaotic circuit converter and the Chen's attractor.