Joint FEC coding and linear precoding for MIMO ISI channels

In this paper, we present a joint forward-error-correction (FEC) coding and linear precoding scheme for multiple-input multiple-output (MIMO) and inter-symbol interference (ISI) channels with imperfect channel state information at the transmitter (CSIT). We first study the performance of ideally coded systems. We focus on an average power gain (APG) method that can achieve capacity in the two extreme cases of no CSIT and perfect CSIT. In the more general case, the performance of the APG method improves progressively with the CSIT quality. We then consider the implementation of this APG method in a practically coded system. We propose a unified scheme involving beamforming, water-filling, and diversity coding. The core of the new scheme is a joint FEC coding and linear precoding strategy at the transmitter and an iterative detection process at the receiver. Simulation results demonstrate that the proposed scheme can achieve significant performance gain by efficiently utilizing the available CSIT.