Decision-Directed Beamforming and Channel Equalization Algorithm for IEEE 802.11n OFDM Systems

In this paper, a decision-directed beamforming and channelequalization algorithm is presented for IEEE 802.11n OFDM systems in the presence of co-channel interference (CCI). Based on the minimum mean-square error (MMSE) criterion, the cost function of the proposed algorithm is to minimize the MSE on each subchannel and to improve the system performance. The beamforming compensation isprimarily used to suppress CCI. The channel equalization is employed to combat the baseband equivalent channel variations induced by multipath fading channel and adaptation of beamformer. The simulations are done for the multipath frequency-selective fadingchannel with CCI to demonstrate that the proposed algorithm can effectively eliminate CCI and compensate the channel distortions. Finally, an FEQ design is done by FPGA evaluation.