Weighted space-time bit-interleaved coded modulation

We present a novel structure to efficiently exploit channel state information at the transmitter (CSIT) of a multiple-input multiple-output system. At the heart of our transmission scheme lies a mixing matrix that constructively combines the coded symbols before a CSIT-dependent weighting matrix is applied. A method to design the mixing matrix is presented. When combined with turbo-coded modulation, our system performs very close to the capacity limits. With only a few bits per channel use to feedback CSIT, we can achieve a substantial portion of the possible gain with perfect CSIT.