基于后验概率估计的软输出MMSE MIMO排序串行干扰抵消检测算法

A posteriori probability based soft-output MMSE MIMO ordering sequential interference cancellation detection

该文研究了信道编码无线MIMO通信系统中的软输出MMSE排序串行干扰抵消检测算法。利用MMSE滤波器输出的高斯近似表示,提出了基于后验概率估计的判决误差传播抑制算法,以提高检测算法输出的编码比特对数似然比的可靠性;利用检测器的矩阵结构和矩阵求逆引理,进一步提出了降低复杂度的实现方法。仿真结果表明:提出的检测算法优于现有算法,当BER为10-4,在所给的仿真条件下有1～3dB的性能增益。

For channel coded wireless multiple-input multiple-output （MIMO） communication systems, soft-output minimum mean square error （MMSE） ordering sequential interference cancellation （OSIC） detection is investigated in this paper. By Gaussian approximation of the output of MMSE filter, a posteriori symbol probability estimation based scheme is proposed to suppress the impact of error propagation due to imperfect interference cancellation so that the reliability of the log-likelihood ratio of each coded bit can be improved. According to the matrix structure of the detector, complexity-reduced implementation is also proposed by utilizing the matrix inverse lemma. The results show that the proposed detector outperforms the existing detectors with gains of 1-3dB at BER=104.