基于判决反馈的OFDM系统相位噪声抑制算法

Phase Noise Suppression Algorithm Based on Decision Feedback in OFDM System

针对正交频分复用系统易受相位噪声的影响,提出了一种基于判决反馈的相位噪声抑制算法,在采用导频子载波对公共相差进行粗略估计的基础上,以判决后的数据子载波对公共相差展开进一步的估计,并利用已优化的公共相差估计值对数据子载波进行重新校正.仿真结果表明,该算法可以在不改变原有系统符号结构的基础上,获得比传统基于导频子载波算法更好的公共相差估计性能,使系统对相位噪声的抑制能力得到提高.

The OFDM system is very sensitive to phase noise. The paper proposes a decision feedback phase noise suppression algorithm, where decision-data subcarriers are utilized for further estimation of the CPE after using the pilots for coarse estimation and the optimized estimation value is used to calibrate the data subcarriers. The simulation results indicate that the algorithm is very effective to accurately estimate the CPE, suppress the effects of it and improve the system performance without modifying the symbol structures in an OFDM system.