SAGE信道估计算法在部分相关STTC-MIMO系统中的应用

SAGE-Based Channel Estimation Algorithm Applied in Partially Correlated STTC-MIMO System

利用天线空间相关函数和方向特性将完全不相关的信道衰落矩阵映射为更符合实际的部分相关MIMO(multiple input multiple output)信道衰落矩阵,结合STTC(space-time trellis code)空时编码方式建立部分相关的STTC-MI MO系统,并将基于SAGE(space-alternating generalized expectation-maximization)的信道估计算法应用在这一系统中.结果显示,和ML(most-likelihood)估计相比,部分相关信道中使用SAGE估计算法可以使系统信噪比提高约1dB.此外,空时编码(space-time codes)的纠错性能对MIMO系统的信噪比也有极大的影响.

A partially correlated multiple input multiple output （MIMO） fading channel model is estabilished by mapping the totally uncorrelated channel fading matrix using antenna spatial correlation functions and antenna patterns. The partially correlated STTC-MIMO system is built on the combination of space-time trellis code （STTC） and the patially correlated MIMO channel. Then a channel estimation method based on space-alternating generalized expectation-maximization （SAGE） algorithm is applied in this system. Compared with most-likelihood （ML） estimation, SAGE can improve the signal to noise ratio of the system by 1 dB. Space-time codes also have a great impact on the performance of the system.