Linear pre-coding for high K-factor channels exploiting channel mean and covariance information

We derive an approximate ergodic capacity expression for high K-factor Rician channels, where the channel mean is of any rank and the fading channel components are correlated. We propose two sub-optimal linear pre-coding schemes that can improve the ergodic capacity considerably for high K-factor Rician channels. In addition, we introduce another sub-optimal linear pre-coding scheme that can present good performance for all K-factors. We investigate the impact of the fading channel covariance, SNR, the rank of the channel mean, and K-factor on the pre-coding schemes and the achievable ergodic capacity limit.