MIMO channel estimation in spatially correlated environments

We present in this paper a novel model-based scheme for estimating MIMO block fading channels. The proposed method can be applied to estimate the conventional independent and identically distributed (i.i.d.) complex Gaussian as well as the more realistic spatial-correlated channels. Excellent mean squared identification error (MSIE) performance can be attained with proper designed system parameters. We also derive an adaptive least squares (RLS) version that can be used for estimating a static channel or tracking time-varying channels. Furthermore, when the angle spread (AS) at the transmit site is small and thus the correlations amongst the transmit antennas are high, we show that it is possible to extract the information about the transmitter's angle of departure (AOD) for potential post-processing applications.