Summary: | 博士 === 國立成功大學 === 工程科學系碩博士班 === 100 === High information correctness and security enhancement are the main objectives of information processing and telecommunication engineering. Information streaming is propagated from one point to another by diversified transmission technologies and mechanisms with electric signals being either wired or wireless. The most important element in communication is synchronization between transmitter and receiver. In other words, excellent synchronization brings high efficiency for decreasing transmission failures. However, considering the demands from a variety of environmental noises, the challenges of design and control for synchronization problems become increasingly difficult. Simultaneously, the reliability of received information can be seriously compromised due to the ceaselessly increasing multi-user and wireless transmissions. As such, this decade has been witness to the rapid growth of various technologies that has generated tremendous changes in synchronization technologies for telecommunications. Currently, the most popular area for synchronization research has been aimed at ensuring and increasing the reliability of information under transmission between two different points under various conditions including time-varying delays of propagation channels and interference from multi-users, among others.
In this dissertation, the stability and performance analysis of a chaos-based communication system has been studied in three separate parts. Firstly, a corresponding electronic horizontal platform system (HPS) with chaotic behavior is designed and implemented; further, a non-coherent coupled chaos-based communication is built based on the proposed electronic design method. Additionally, an output feedback controller is proposed for global synchronization between coupled electronic HPS systems, the stability condition of which is derived by employing the Lyapunov stability theory. Then, the chaotic behavior of the electronic HPS is verified with the largest Lyapunov exponent. In the second part, by combining the Lyapunov stability theory with the linear matrix inequality (LMI) optimization technique, a reliable feedback controller is established to guarantee synchronization between the master and slave chaotic systems despite the occurrence of some control component (actuator) failures. Following this, an illustrated example is provided to demonstrate the effectiveness of the developed system, both with and without the actuator failures. In the third part, numbers of non-coherent coupled chaotic communication systems denoted by the Lorenz system work as a Multi-Input-Multi-Output (MIMO) structure in a wireless channel with the Additive White Gaussian Noise (AWGN) effect. In this structure, information symbols are covered and encrypted with chaotic dynamics of the Lorenz system at the transmitter side. Then, information decryption processing is completed by synchronization control design of the Lorenz system at the receiver side. And finally, an SNR (Signal to Noise Rate)-to-BER (Bit-Error Rate) diagram is illustrated as a correctness indicator of the proposed structure.
|