Low complexity iterative receiver for non-orthogonal space-time block code with channel coding

In this paper, we study the association of nonorthogonal space-time block coding (NO-STBC) with channel coding and propose an efficient iterative receiver. For two transmit antennas, the use of the Alamouti scheme as STBC is optimal owing to its orthogonality and its unitary rate. For more than two antennas, full rate is maintained by giving up the orthogonality. This nonorthogonality makes the decoding often complex and sub-optimal in terms of exploitation of the diversity. In this paper, we present a low complexity receiver based on iterative process performing jointly space-time decoding and channel decoding. Simulations over uncorrelated Rayleigh flat fading channels show that such a receiver exploits at best the space-time diversity provided by the nonorthogonal STBC and the channel coding.