The performance of a Single Code Word (SCW) design with low complexity MMSE receiver & rank prediction is similar to the Multiple Code Word (MCW) design with successive interference cancellation (SIC). A method of rank prediction comprises calculating MIMO channel matrices corresponding to layer transmissions for each tone, calculating signal-to-noise ratios (SNRs) for each tone based on the MIMO channel matrices, mapping the SNR for each tone to generate effective SNRs for each layer transmission, selecting a highest packet format (PF) with an SNR threshold less than the effective SNR for each layer transmission, maximizing an over-all spectral efficiency based on the selected highest packet formats for each layer transmission, and selecting a rank based on maximizing an over-all spectral efficiency.