Further results on blind detection of asynchronous CDMA signals using code-constrained super-exponential algorithm

We revisit the recently presented code-constrained super-exponential algorithm (SEA) (Li-Tugnait, 2001) for blind detection. of asynchronous short-code DS-CDMA (direct sequence code division multiple access) signals over multipath channels. Convergence of the algorithm is proved by showing that the constrained SEA is a special case of "undermodeled" SEA which is equivalent to a gradient search algorithm. Given appropriate initialization, constrained SEA can lead to the extraction of the desired user, whereas unconstrained SEA leads to the extraction of any one of the actives users.