基于迭代加权最小二乘的基扩展模型信道估计

Channel Estimation of Basis Expansion Model Based on Iterative Weighed Least Square

针对载波间干扰引起的接收端待估计参数增加,采用传统估计方法无法求解的问题,提出了基于迭代加权最小二乘(Iterative Weighed Least Square,IWLS)的基扩展模型(Basis Expansion Model,BEM)信道估计方法。首先采用过采样的复指数基扩展模型来拟合信道时变特性,减少了待估计参数;然后通过分析确定性信道矩阵信息进行迭代加权从而得到待估计参数。仿真结果证明了该方法能够有效抵抗吉布斯效应带来的误差平底,且不需要信道的先验统计信息,对多普勒频移有很强的鲁棒性。

An channel estimation method of basis expansion model based on iterative weighted least squares was proposed to solve the problem that the parameters to be estimated increased due to inter-carrier interference and traditional estimation methods were noneffective. Firstly, an over-sampled complex exponential basis expansion model was taken to fit the channel time-varying characteristics and reduced the number of parameters to be esti- mated; then the iterative weighted method was applied to obtain the parameters estimated by analyzing the de- terministic channel matrix information. The simulation results proved that this method could effectively resist the error-floor caused by Gibbs effect, and did not require a priori statistical channel information, which had a strong robustness to Doppler shift.