High rate trellis coded differential unitary space-time modulation via super unitarity

We introduce a new trellis coded differential unitary space-time modulation scheme for multiple-antenna wireless systems. In the new scheme, the constellation expansion is executed using a super unitarity technique so that the number of available unitary matrices is increased but the transmitted symbol alphabet is kept the same. A novel set partitioning strategy is then applied to the expanded matrix set. This scheme avoids the rate-loss problem suffered by traditional code design. We provide some examples using the proposed code construction method. Compared with existing ones, the new codes can not only achieve lower transmitter and receiver complexity, but also provide higher coding gains