A blind multiuser detection algorithm for QS-CDMA systems

In this paper, we present a multiuser detection algorithm for quasi-synchronous code-division multiple-access (QS-CDMA) systems where the receiver has knowledge of the spreading codes of all users originating from the cell of interest, but does not know the spreading codes of the intercell interferers. The algorithm implements a blind linear detector that can recover several signals in a multipath environment. The received signals are decomposed into two sets: a set of observations that contains the user of interest and the interference, and a set of observations that contains only the interference. With this decomposition, the first user can be recovered by a linear interference cancellation algorithm. The second user is recovered using a similar decomposition technique, except that it operates on a set of observations that excludes the first user. The remaining users are sequentially recovered in a similar manner.