An Optimum Sub-Channel Weighting Scheme for MIMO-OFDM Wireless System

In this paper, an optimum sub-channel weighting (OSW) scheme for multiple-input multiple-output with orthogonal frequency division multiplexing (MIMO-OFDM) wireless receiver design is proposed to enhance the signal-to-noise ratio (SNR) with time-varying fading channels. The Bayes decision algorithm is implemented to calculate the spatial sub-channel weighting factors, where the M-likelihood optimum decisions for the received signal thresholds are determined. Instead of optimal waterpouring power allocation, this scheme effectively increases the mean SNR value invoked with an optimum channel covariance under total transmitted power constraint. Eigen-analysis shows that the cumulative distribution function (cdf) of the eigenvalues generated using the optimum decision rule is considerably better than that of the original one even in the presence of spatial correlation across antennas and maximum Doppler frequency.