Combining turbo code and multilevel space-time modulation in rapid Rayleigh fading channels

Unitary space-time modulation (USTM) can perform well without channel state information (CSI) in fast fading channels when signal-to-noise ratio (SNR) is large enough. However, it loses its advantages at low SNR or the channel coherence interval is T = 1. In this condition, the information should be carried by multilevel structured constellations with single transmit antenna. In this paper, we propose a simple non-coherent multilevel space-time modulation (MSTM) scheme, combine it with turbo coding, and derive the corresponding decoding algorithm. Simulation results verify that it can greatly improve the system performance. Finally, we propose an indirect method to get the extrinsic information transfer (EXIT) chart and analyze the convergence characteristics.