Space-Time Transmit Diversity Schemes with Low-Density Parity-Check (LDPC) Codes

Space-time transmit diversity (STTD) and space-time block coding (STBC) are attractive techniques for high bit-rate and high capacity transmission. The concatenation scheme of turbo codes and STBC (Turbo-STBC) was proposed and it has been shown that the Turbo-STBC can achieve the good error rate performance. Recently, low-density parity-check (LDPC) codes have attracted much attention as the good error correcting codes achieving the near Shannon limit performance like turbo codes. The decoding algorithm of LDPC codes has less complexity than that of turbo codes. Furthermore, when the block length is large, the error rate performance of the LDPC codes is better than that of the turbo codes with almost identical code rate and block length. In this letter, we propose a concatenation scheme of LDPC codes and STBC. We refer to it as the LDPC-STBC. We evaluate the error rate performance of the LDPC-STBC by the computer simulation and show that the error rate performance of the LDPC-STBC is almost identical to or better than that of the Turbo-STBC in a flat Rayleigh fading channel.