Abstract
Under the condition of keeping Duffing system in chaotic state, we present a method of changing the center position by adding a non-smooth periodic signal to Duffing system. In this paper, we first make a theoretical analysis which describe the influence of added signal on center point of Duffing system and provide mathematical proofs, and then build a simulation system which can change the center position of Duffing system. Finally, computer simulations are used to verify the analytical results. Simulation results show that the proposed method can effectively work in secure communication applications.