Combined turbo coding and non-coherent space-time modulation in rapid Rayleigh fading channels

Abstract

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 a single transmit antenna. Even though, the bit error rate (BER) of this kind of signalling scheme is still too high to accept. In this paper, we propose a simple non-coherent space-time modulation scheme, combine it with turbo coding, and derive the corresponding decoding algorithm. Simulation results show that it can greatly improve the system performance. With multiple receive antennas, the BER can be further decreased.