A chip semiblind receiver for STBC downlink MC-CDMA systems without cyclic prefix

In this paper, we propose a space-time chip semiblind receiver for space-time block-coded downlink MC- CDMA without cyclic prefix. The receiver distinctly exploits advantage of training and blind modes for updated algorithm using an adaptive mixing parameter. The AS-LMS is incorporated in a semiblind update function, which in turn improves the performance of the receiver in frequency- selective fading channel. The receiver restores efficiently the orthogonality of the user´s signals and suppress MAI. Detection of the desired user requires only the knowledge of the desired user code matrix. The simulation result shows that the proposed semiblind receiver has achieved an improvement of the transmitted power over the space-time chip training- based and semiblind receivers in modified Pedestrian A channel model. Moreover, the receiver has lower computational complexity than existing space-time chip receivers.