Code Design of Space-Time Block Codes Coded Low-Density Parity-Check Code and System Performance Analysis
Wang Lan-xun, Li weizhen · 2007
In Multiple Input and Multiple Output system of wireless communications, Space time coding using multiple transmit antennas is the attractive technique for high bit-rate and high capacity transmission. Methods for providing transmit diversity in communication over fading channels also been concerned. Although Space-Time Block Codes has full diversity gain but not coding gain. The concatenation scheme of STBC codes and LDPC (STBC-LDPC) was proposed and it has been shown that the STBC-LDPC can achieve the good error rate performance and coding gain. Low-density parity-check (LDPC) codes, as it is the good error correcting codes achieving the near Shannon limit performance. In this paper, a concatenation scheme of LDPC codes and STBC which should apply full transmit rate with multiple transmit antennas is proposed. Refering to it as the ABBA-LDPC and OSTBC-LDPC. We evaluate the bit error rate (BER) of the two schemes in a quasi-static Rayleigh fading channel by the computer simulation. We show that the BER of the ABBA-LDPC is better than that of the STBC with same antennas in a quasi-static Rayleigh fading channel, and also it is better than OSTBC-LDPC which uses real constellation. When receive antennas increasing, the diversity gain will be increasing too.