基于LDPC编码的MIMO系统迭代接收机研究

研究了基于LDPC编码无线MIMO通信系统中的软输出最小均方误差干扰抵消迭代(MMSE PIC)检测算法。针对初次迭代检测时PIC输出的后验比特对数似然比(LLR)不可靠的问题,利用MMSE滤波器输出的高斯近似表示,给出了基于后验概率估计的迭代干扰抵消检测算法,以提高检测器输出的编码比特对数似然比的可靠性。仿真结果表明:改进的检测算法优于现有算法。

The article focused on the soft output minimum mean^quare error（MMSE）paralleling soft interference cancellation（PIC） iterative detection algorithm of LDPC coded MIMO Systems. According to the problem that the output bit log-likelihood ratio（LLR） of PIC is unreliable in the first iterative detection, with approximation of Gauss model ,an iterative interference cancellation algorithm based on the posteriori probability estimation is proposed to improve the reliability of the output bit log-likelihood ratio（LLR）of the detector. The simulation results show that the proposed algorithm performs better than the present.