A Design of Chaotic Cryptosystem Based on Linear Controller Parameterization

Abstract

A general methodology for designing chaotic and hyperchaotic cryptosystems was developed using the control systems theory. Grassi proposed a nonlinear-observer-based decrypter for the state of the encrypter. If we can design the decrypter without the knowledge of the parameters of the encrypter, the chaos-based secure communication systems are not secure. In this paper, we propose an observer-based chaotic communication system, which allows us to assign the relative degree and the zeros of its encrypter system. Moreover, we design a robust synchronizer based on linear controller parameterization.