引入加权系数消除ICI的二次快时变信道估计算法

针对高速移动环境下由多普勒频移引起的子载波间干扰（inter-carrier interference，ICI），提出一种引入加权系数消除ICI的二次快时变信道估计算法。该算法进行两次信道估计，第一次估计用于提供信道状态信息，在保证符号率的前提下消除ICI，第二次估计在ICI消除的情况下进行，可以提高信道估计精度；并对简化的并行干扰消除（parallel interference cancellation，PIC）算法进行改进，基于最小均方误差准则引入加权系数，使得ICI消除后的残余误差最小。仿真结果和理论分析达到很好的一致性，当信道信噪比为0 dB时，归一化均方误差（normalized mean square error，NMSE）性能增益最大约为0.0714，提高了快时变信道估计的精度。

Twice rapidly time-varying channel estimation algorithm based on ICI cancellation using weighted coefficient

This paper proposed a twice channel estimation algorithm, in which used weighted coefficient to cancel Inter-Carrier Interference (ICI) caused by Doppler frequency shift in high speed mobile environment. The algorithm achieved twice channel estimation. The first estimation provided channel state information to cancel the ICI under the premise of ensuring the symbol rate; in the case of ICI cancellation, the second estimation enhanced the channel estimation accuracy. Then the algorithm improved the simplified parallel interference cancellation (PIC) algorithm, and introduced the weighting coefficient to make the residual error smallest after ICI cancellation based on the minimum mean square error criterion. The simulation results are in good agreement with the theoretical analysis. The proposed algorithm improves the estimation accuracy of rapidly time-varying channels. The maximum value of normalized mean square error (NMSE) performance gain is 0.0714, when the SNR is 0dB.