Design of concatenated space-time block codes using signal space diversity and the Alamouti scheme

New full-rate space-time block codes achieving full diversity for QAM modulation using an even number of transmit antennas over quasistatic Rayleigh fading channels are proposed. The proposed codes are constructed by serially concatenating unitary rotating precoders in X. Giraud et al. (1997) and Y. Xin et al. (2001) with the Alamouti code of S. M. Alamouti (1998). The coding advantage (V. Tarokh et al., 1998) of the proposed code for a codeword pair corresponding to any distinct input pair is shown to be greater than or equal to that of the ST-CR code (Y. Xin et al., 2001).