High-rate concatenated space-time block code M-TCM designs

In this paper, a new technique to design improved high-rate space-time (ST) codes is proposed based on the concept of concatenated ST block code (STBC) and outer trellis-coded modulation (M-TCM) encoder constructions. Unlike the conventional rate-lossy STBC-MTCM schemes, the proposed designs produce higher rate ST codes by expanding the codebook of the inner orthogonal STBC. The classic set partitioning concept is adopted to realize the STBC-MTCM designs with large coding gains. The proposed expanded STBC-MTCM designs for the two-, three-, and four-transmitter cases are illustrated. Simulation results show the proposed STBC-MTCM designs significantly outperform the traditional ST-TCM schemes. Furthermore, decoding complexity of the proposed scheme is low because signal orthogonality is exploited to ease data decoding.