一种基于导频OFDM信道估计的优化算法

信道估计作为OFDM 中的一项关键技术，直接影响着OFDM 系统的性能。而现有
的最小二乘估计（LS）算法、最小均方误差估计（MMSE）算法等都存在各自的不足。因此本文提出了一种称为平均反馈（AF）的新算法，该算法利用两个相邻的OFDM 符号之间的关联信息对LS 算法的估计结果进行平均和反馈，以减少高斯白噪声与子信道间干扰（ICI）对信道估计结果的影响。通过仿真证明，新算法改善了LS 算法的性能，尤其在低信噪比环境下的性能改进明显。
【关键词】正交频分复用 信道估计 最小二乘估计平均反馈算法
【Abstract】 Channel Estimation technique is one of the key techniques in OFDM and it directly affects the performance of the system. Some existing methods, such as LS method and MMSE method, having some obvious shortcomings respectively. So an improved method is proposed in this paper. The optimal method reduces the interfere of noise and ICI by using the related information between two adjacent OFDM symbols to feedback and average. At last, the simulation result demonstrates that, compare with original LS methods; new methods improve the BER performance, especially in the low SNR environment.
【Key words】 OFDM channel estimation least square(LS) average feedback (AF)