基于二维DFT的多导频模式OFDM信道估计算法  

Channel estimation algorithm based on 2-D DFT with multiple pilot patterns in OFDM systems

作　　者：葛启宏[1] 陆建华[1] 梅顺良[1] 

机构地区：[1]清华大学电子工程系,北京100084

出　　处：《清华大学学报（自然科学版）》2004年第6期821-824,共4页Journal of Tsinghua University(Science and Technology)

基　　金：国家自然科学基金资助项目 ( 60 13 2 0 10)

摘　　要：提出了一种正交频分复用 (orthogonal frequencydivision multiplexing,OFDM)系统中的抗噪声信道估计算法 ,适用于块状、梳状、格形和菱形导频模式。该算法通过导频位置偏移量预校正、二维离散 Fourier变换 (DFT)和变换域滤波消除噪声的影响 ,利用变换域补零和二维反离散Fourier变换进行信道传输函数插值 ,并使用变形 cos窗抑制插值过程中的频谱扩散。仿真结果表明 :该算法的系统性能明显优于传统信道估计算法 ,采用该算法获得了约 2 d B的每 bit信噪比增益。该算法在宽带A noise-resilient channel estimation algorithm was developed for orthogonal frequency division multiplexing (OFDM) systems for comb, block, grid, and diamond pilot patterns. The effect of channel noise was mitigated with pre-correction of the pilot slippage, two-dimensional discrete Fourier transforms and filtering in the transformed domain. Zero padding and two-dimensional inverse discrete Fourier transforms were used to interpolate the channel transfer function, with a modified cosine window used to reduce the spectral leakage due to the interpolation. The simulation results show that the system performance with the proposed algorithm is significantly improved compared with the traditional Least Squares estimate, having a 2 dB better signal-to-noise ratio per bit. The algorithm can be used to improve wide-band OFDM systems.

关 键 词：移动通信 正交频分复用(orthogonal frequency DIVISION multiplexing OFDM) 信道估计 二维离散Fourier变换 多导频模式 抗噪声 

分 类 号：TN929.5[电子电信—通信与信息系统]