一种基于改进Lloyd-Max的信道估计算法

摘要

The existing channel estimation algorithm based on Lloyd-Max has low accuracy and can not deal with high order QAM signal.To solve the problem,the paper proposes an algorithm based on improved Lloyd-Max.Given the modulation pattern,the algorithm imposes a constellation structure constraint on the cluster process of the Lloyd-Max algorithm,which avoids the deformity of the constellation result from the clustering,so it can increase the estimation accuracy of the fading coefficient.The simulation results indicate that the proposed method has higher accuracy than Lloyd-Max under low SNR,which is more evident when the modulation order is high.%针对基于Lloyd-Max的平衰落信道估计算法估计精度低且无法适用于高阶QAM调制的问题,提出了基于改进Lloyd-Max的信道估计算法.该算法结合信源的具体调制样式,对Lloyd-Max算法的聚类过程施加星座图结构约束,从而避免了聚类后星座图结构畸形的问题,提高了信道参数估计精度.仿真试验表明,该算法相比于Lloyd-Max算法在较低信噪比下具有更高的信道参数估计精度,在调制阶数较高时,这种优势更加明显.