Secure communication system in maritime navigation using state observer with linear matrix inequality

Abstract

With emerge of smart navigation, the secure communication issues have drawn extensive attention on maritime agendas between ships or with the shore. This paper presents a chaotic secure communication scheme by using observer design for maritime navigation and transportation systems. The proposed scheme involves three key factors: chaotic encryption, state observer, and chaotic decryption. The chaotic system, as the encryption keys carrying confidential information, will be sent from transmitter to the receiver through a public channel. It is obvious that the fewer signals are transmitted on the public channel, the higher security of the communication system is possible. A state observer is designed to estimate all system states when only partial states are detectable on the public channel. The robust observer gain is implemented in terms of linear matrix inequality (LMI) for convex optimization. The process of information encryption and recovery has been discussed in detail. From the simulation results, it is found that the observer-based method can robustly estimate full state variables by using system output signals with LMI optimization. Based on these updated states with the the state observer, the original information is accurately recovered for safe navigation of vessels with reliability and efficiency.