正交频分复用子载波间干扰抵消的迭代算法

为了解决正交频分复用(OFDM)中由频率偏移和D opp ler扩展带来的载波间干扰问题,结合T urbo信道编码软输入软输出信息,提出一种用于载波间干扰抵消的匹配迭代算法。该算法利用信道译码输出软信息来当作信息比特的先验信息,从而根据子载波间干扰矩阵来消除对其他载波点上的干扰分量,经过若干次迭代来达到性能优化。与传统的子载波干扰自消除、频域抽头滤波算法以及简单的匹配算法比较,其结果可以消除误码平台;与整体频域均衡算法比较,可以在避免求大型矩阵逆的复杂算法上获得更好的性能优势。

Iterative inter-carrier interference cancellation in OFDM systems

A matched iterative ICI cancellation algorithm with Turbo code soft-in soft-out was developed to reduce inter-carrier interference due to frequency offsets and Doppler spread in orthogonal frequency division multiplexing(OFDM) systems.This algorithm uses the soft-out extrinsic information of the Turbo code as prior transmitted information by which part of the channel ICI can be subtracted from the received signals.After several iterations,the algorithm gives good results.Compared with the traditional ICI self-cancellation,the tap-filter method,and matched detection,this algorithm removes the error floor in high SNR environments.Compared with the entire frequency equalizer,this algorithm has better performance because it avoid the large matrix inversion.