The Controlling And The Cryptographic Application Of Coupled Map Lattices

Two kinds of researches are presented in this dissertation. The first one is to control the spatiotemporal chaos (STC) of coupled map lattices (CML) to the homogeneous state and the homogeneous periodic orbits. The second one is to make use of the complexity of STC in CML to build a cryptosystem.In the research of the controlling of STC, we use nonlinear feedback to control STC of CML to the homogeneous state and the homogeneous periodic orbits. Stability analyses are presented. Simple and sufficient conditions are obtained for successful controlling. Numerical simulations agree well with theoretical results. Basin of attraction is discussed in the controlling of the homogeneous periodic orbits because the basin of attraction of these orbits are small.In the research of the application of CML to cryptography, CML is used to build a block cipher based on one-time pad technique. The cipher is so built that the progress in decryption means also the progress on exploring the spatiotemporal chaos of CML.