Kurtosis based maximization/minimization approach to blind equalization for DS/CDMA systems in unknown multipath

In this paper, we study blind equalization for a DS/CDMA system in multipath. The kurtosis of the equalizer´s output is maximized with respect to the equalizer´s parameters subject to multiple linear constraints. The constraints are dependent on the spreading codes of the user of interest. In order to optimally combine signals from multiple propagation paths, we parameterize the kurtosis by the constraint vector as well and further minimize the maxima of kurtosis to obtain the optimal constraints. It is shown that the constraint vector converges to the channel vector of the desired user irrespective of noise. The equalizer guarantees cancellation of both intersymbol interference and multiuser interference.