Channel estimation for wireless OFDM systems

A channel estimation technique is developed for an OFDM system with multiple transmit and multiple receive antennas. The approach exploits the channel structure in the time domain and the frequency domain. The method is appropriate for OFDM systems operating in a time varying channel. A multi-input-multi-output OFDM (MOFDM) system model is defined, followed by a proposed excitation strategy for sufficient identification of the channel. The estimation strategy is shown to be optimal within the class of linear MMSE estimators. Experimental results of the algorithm are provided.