Performance of blind adaptive receiver with decision directed steering vector

We consider a blind single-user type detector known as an orthogonalizing matched filter (OMF) for implementation in mobile stations of DS-CDMA systems. Its performance is degraded when the actual received signature waveform deviates from the one assumed in the detector in a multipath environment. In order to surmount this problem, a multiple finger expansion optimal filter (MFE-OF) was proposed, which offers better performance when sufficient fingers were employed. In this paper, a modification to the MFE-OF is introduced by utilizing a decision directed steering vector to provide performance enhancement without employing as many fingers as the conventional MFE-OF. Computer simulation verifies the effectiveness of this new receiver, which we refer as the decision directed optimal filter (DDOF), to increase the forward-link capacity in CDMA systems