Title :
Toward sequences optimization for chaos-based asynchronous DS-CDMA systems
Author :
Rovatti, Riccardo ; Setti, Gianluca ; Mazzini, Gianluca
Author_Institution :
Dipt. di Elettronica, Inf. e Sistemistica, Bologna Univ., Italy
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 environment
Keywords :
cellular radio; chaos; cochannel interference; code division multiple access; interference suppression; m-sequences; nonlinear dynamical systems; optimisation; quantisation (signal); spread spectrum communication; Gold sequences; cellular communications; chaos-based asynchronous DS-CDMA systems; chaos-based sequences; cochannel interference reduction; communication systems theory; maximum-length sequences; multilevel spreading codes; nonlinear dynamical systems theory; one-dimensional chaotic systems; optimization; performance; quantized chaotic time series; sequence generation; sequences optimization; spreading sequences; Additive white noise; Chaos; Chaotic communication; Character generation; Communication systems; Electronic mail; Gaussian noise; Gold; Multiaccess communication; Wideband;
Conference_Titel :
Global Telecommunications Conference, 1998. GLOBECOM 1998. The Bridge to Global Integration. IEEE
Conference_Location :
Sydney,NSW
Print_ISBN :
0-7803-4984-9
DOI :
10.1109/GLOCOM.1998.775920
