Adaptive frequency-domain equalization for single-carrier MIMO systems

Channel estimation and tracking pose real problems in wideband single-carrier wireless communication systems employing multiple transmit and receive antennas. An alternative to estimating the channel is to adaptively equalize the received symbols. In this paper, we present an adaptive equalization algorithm for implementation in multiple-input multiple-output (MIMO) single-carrier (SC) systems with frequency-domain equalization (FDE). Furthermore, we outline a novel method of reducing the overhead required to train the adaptive equalizer. Other computationally efficient adaptive MIMO SC-FDE algorithms can only be applied to space-time block-coded (STBC) architectures. The algorithm detailed in this paper can be implemented in STBC systems as well as in broadband spatial multiplexing systems, making it suitable for use in high data rate MIMO applications.