Function projective lag synchronization in a class of chaotic systems with unknown parameters

Considered the inevitable time delay in the practical synchronization, the function projective lag synchronization (FPLS) is investigated in this paper, which makes the states of two chaotic systems asymptotically lag synchronized up to a desired scaling function. Based on adaptive control scheme, the adaptive control law and the parameter update law are derived for a class of chaotic systems with unknown parameters. We take Lorenz system as an example to verify the effectiveness of the proposed scheme. Theoretical analysis and numerical simulation demonstrate the effectiveness of this method.