A model to characterize the performance of asynchronous CDMA systems with multilevel spreading codes based on periodical repetition of quantized chaotic time series is presented. Some analytical tools for performance investigation are described which merge communication and non-linear dynamical systems theories. With the help of these analytical tools and of extensive optimization, some new one-dimensional chaotic systems are constructed which can be effectively used for sequence generation. As a result of these optimization effort, examples of chaos-based sequences outperforming the classical spreading sequences (maximum-length and Gold sequences) are reported. Performance gains up to 23% are obtained considering a realistic environment
Toward sequences optimization for chaos-based asynchronous DS-CDMA systems
SETTI, Gianluca;MAZZINI, Gianluca
1998
Abstract
A model to characterize the performance of asynchronous CDMA systems with multilevel spreading codes based on periodical repetition of quantized chaotic time series is presented. Some analytical tools for performance investigation are described which merge communication and non-linear dynamical systems theories. With the help of these analytical tools and of extensive optimization, some new one-dimensional chaotic systems are constructed which can be effectively used for sequence generation. As a result of these optimization effort, examples of chaos-based sequences outperforming the classical spreading sequences (maximum-length and Gold sequences) are reported. Performance gains up to 23% are obtained considering a realistic environmentI documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.