A first experimental verification of optimal MAI reduction in chaos-based DS-CDMA systems

Recently, some of the authors derived a sufficient condition to obtain asynchronous DS-CDMA systems in which the MAI at the output of a classical correlation receiver is brought to its absolute minimum. Such a sufficient conditions constraints the autocorrelation function of the spreading sequences used to distinguish users to be real and of alternating sign. They also proved that such an autocorrelation profile can be almost perfectly matched by employing a properly designed family of chaotic systems and by using it to design real trajectories that are then quantized and periodically repeated to yield the users signatures. We report a preliminary experimental verifications of this theoretical prediction confirming that chaos-based spreading sequences outperform classical m- and Gold sequences when MAI is the dominant cause of error.

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