Combining Bigen-Beamforming and Cyclic Delay Diversity for Correlated MISO Channels with Block-Iterative GDFE Receiver

In this paper, we consider the performance enhancement of signal detection for single carrier-cyclic prefix (SC-CP) transmissions over correlated multiple inputs single outputs (MISO) channels. The block-iterative generalized decision feedback equalizer (BI-GDFE) receiver is used to combat the effect of intersymbol interference (ISI). While BI-GDFE outperforms linear equalizers, the improvement could be limited if the channel does not contain a high degree of frequency-selectivity. On the other hand, direct application of cyclic delay diversity (CDD) to a highly correlated MISO channel generally cannot increase the frequency diversity significantly. In this paper, we propose combining eigen-beamforming and CDD for frequency diversity enhancement, with which the performance of the BI-GDFE is also greatly improved. Computer simulations show that the proposed system not only offers diversity improvement but also beamforming gain. It is also observed that the BER performance of the proposed system can approach its matched filter bound (MFB)