Kalman tracking of time-varying channels in wireless MIMO-OFDM systems

The performance of coherent MIMO-OFDM systems critically depends on the availability of accurate channel estimates. In wireless communications, the MIMO channel is time-varying and thus has to be tracked by the receiver. In this paper, we develop an extended Kalman filter technique for pilot symbol assisted MIMO-OFDM channel tracking. Our tracking scheme is able to exploit spatial correlations of the channel. It includes on-line estimation of the channel´s state-space parameters and hence does not require any prior knowledge. Simulations using measured channels demonstrate the excellent performance of our channel tracking scheme.