On the performance of chaos-based multicode DS-CDMA systems

Multicode DS-CDMA systems assign more than one spreading sequence to each of the users. In these systems multiple access interference (MAI) is made of a synchronous and an asynchronous component. It is well known that asynchronous MAI alone can be minimized by means of chaos-based spreading. Here we address the trade-off between synchronous and asynchronous MAI by tuning the autocorrelation profile of the chaos-based spreading codes. Improvements in the number of users allowed in the system is demonstrated in certain load conditions with respect to the classical approach of providing each user with a set of orthogonal sequences taken from an i.i.d. process.