Bit-Wise Error Detection Based Iterative Signal Detection for OFDM MIMO Multiplexing

Recently, we proposed an iterative modified QR-decomposition based M-algorithm (QRD-M) using decoding results of cyclic redundancy check (CRC) code for OFDM MIMO multiplexing. The symbol-wise CRC decoding results are used in the transmit antenna ranking and in the modified M-algorithm. Hereafter we call this iterative QRD-M as symbol-wise iterative modified QRD-M. In this paper, to further improve the transmission performance of OFDM MIMO multiplexing, we replace the use of symbol-wise CRC decoding results by the use of bit-wise CRC decoding results. The symbol replica candidates for the transmitted symbol are re-ordered using the bit-wise CRC decoding results in the modified M-algorithm. Computer simulation results show that when 16QAM data-modulation is used, an E_b/N₀ reduction of about 0.6~0.7 dB can be achieved for average packet error rate (PER)=10^-2 compared to the symbol-wise scheme.