On the Effect of Imperfect Channel Estimation upon the Capacity of Correlated MIMO Fading Channels

This paper deals with the impact of channel estimation errors on the capacity of correlated fading MIMO channels. In literature the effect of channel uncertainty at the receiver is often investigated with the assumption that channel estimation errors are identically distributed and independent of both SNR and channel correlation values. In this paper we extend the analysis by considering correlation among the channel estimation errors as typically happen when the MIMO channel to be estimated is spatially correlated. We propose and study upper and lower bounds on the MIMO channel capacity giving emphasis to the impact of the resulting channel estimation error, through its covariance matrix. The role played by the effective SNR and spatial correlation is studied by detailing the results to MIMO systems employing linear MMSE channel estimators.