Mutual Information of MIMO Transmission over Correlated Channels with Finite Symbol Alphabets and Link Adaptation

In this paper, results on the mutual information of MIMO transmission over spatially correlated channels in slow fading environments are presented. Different receiver techniques such as optimal maximum likelihood detection, parallel layer detection, successive interference cancellation detection and linear detection are compared. The transmit signals are derived from finite signal alphabets such as M-QAM. Different degrees of adapting the transmit signals to the channel state are taken into account. Results show that the gap between successive interference cancelation and maximum likelihood detection almost vanishes in a 2×2 MIMO transmission setup if link adaptation can be applied, regardless of spatial correlation.