Blind multiuser detection using linearly constrained minimum variance filters

We propose a new blind multiuser detector for the frequency selective multipath channels. The new linearly constrained minimum variance (LCMV) RAKE receiver is an enhancement to the previously published decorrelating RAKE (D-RAKE) receiver. Compared with the D-RAKE receiver, the LCMV-RAKE receiver processes full information of the desired user and is shown by simulations to have lower bit error rates. Furthermore, the LCMV-RAKE receiver is not limited to the quasi-synchronous model, where the maximum delay spread is assumed to be small compared to the symbol duration.