A semiblind receiver for space-time block-coded downlink multirate DS-CDMA systems

In this paper, a novel space-time block-coded (STBC) semiblind receiver for wideband code division multiple access (WCDMA) downlink multirate is proposed. The receiver exploits distinct advantages of training based and blind update algorithms by means of an adaptive mixing parameter. The training is updated using continually transmitted pilot code sequence as the training signal whereas the blind part uses the decision directed estimate. Unlike the existing pilot-based receivers, the proposed receiver employs a multiple constraint to give the exact solution for detection of the desired user. Moreover, the proposed receiver needs reduced transmitted power and lower computation complexity than the space-time chip receivers.