Symbolic dynamics for processing chaotic signal. II. Communication and coding

For pt. I see ibid., vol. 48, no. 11, p. 1269-82 (2001). The idea of using chaotic signals in different layers of communication systems has attracted the attention of researchers as well as engineers and many encryption, coding, and modulation schemes have been proposed in recent years. One promising application is to employ chaotic codes in broadband communication with the intention of achieving a better immunity to multipath degradation and self-interference, exploiting the nonperiodicity of chaotic signals. The main drawback is that an optimum, coherent detection cannot be implemented since a synchronized reference signal on the receiver side has been, so far, only realizable for a finite number of code-words. This paper provides the analysis and results (theoretic and numerical) regarding design and optimization of chaos-based communication schemes, in particular: 1) performance limits for optimum coding and decoding schemes are derived, that are based on an infinite number of finite-length chaotic sequences that are generated by a special class of chaotic systems; 2) identification of fundamental differences between a finite set of conventional block codes and chaotic codes; and 3) development of optimization rules for chaotic codes.