Spatial signature and channel estimation for wireless MIMO-OFDM systems with spatial correlation

This work extends the time delay and spatial signature estimation algorithms proposed by Swindlehurst which are applied in the single-input multiple-output (SIMO) single carrier system to the multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) system by virtue of the specific pilot sequences with cyclic structure for the different transmitters. The receive spatial correlation matrix of the vector channel impulse response (CIR) is formulated as the function of the spatial signature, time delay and the pulse shaping filter. By taking the spatial correlation into account, the joint spatial-temporal (JST) filtering MMSE channel estimator is derived. Their performance is illustrated based on the analysis and computer simulations.