Performance evaluation of the unified linear multiuser receiver

In this paper, we study the performance of the unified linear (UL) multiuser detector (MUD) for code division multiple access. Particularly, we are interested in the conditions where the UL receiver is capable of outperforming the other linear MUD receivers, especially the linear minimum-mean-square-error (LMMSE) receiver. We obtain an implicit expression that gives the optimal value of the weighting factor (λ) (for the two user case) that minimizes the probability of error for a desired user. Furthermore, we propose a modified version of the UL receiver that can achieve a lower average probability of error than the LMMSE receiver for all users.