Control of Chaos Statistics for Optimization of DS-CDMA Systems

Results of recent theoretical investigations highlighted that the use of chaos in DS-CDMA systems may lead to non-negligible improvements in communication quality for several scenarios. We here briefly review the main steps in this derivation and report the corresponding theoretical prediction. In particular we show that the use of the so-called statistical approach to the study of a chaotic dynamical system allows to characterize and control the statistical features of the processes generated by it. By using such an approach, we highlight the path leading to the generation of chaos-based spreading sequences outperforming classical pseudo-random sequences in two important cases. Over non-selective channels, the ability of chaos-based spreading of minimizing multiple-access interference leads to an average improvement of 60% in Perr with respect to classical spreading. Over selective channels, the possibility of jointly optimizing chaos-based spreading and rake receiver profiles leads to improvements of up to 22% in Perr with respect to systems with either conventional spreading or conventional rake policies.