Synchronization of the bidirectionally coupled unified chaotic system via sum of squares method

This paper considers the synchronization problem of the bidirectionally coupled unified chaotic system. Many previous works require the assumption that the states of the system are bounded and their range are known. This assumption may not hold for arbitrary controllers, and thus, it is not suitable to make this assumption beforehand. Accordingly, we propose the novel control method for bidirectionally coupled unified chaotic system via sum of squares method without this assumption. Numerical simulations show the validity and advantage of the proposed method.