OFDM系统相位噪声的Huber ML抑制方法

Phase Noise Mitigation Method for OFDM System Based on Huber ML

OFDM系统对相位噪声(PHN)非常敏感,由其引起的子载波相位旋转和载波间干扰(ICI)会严重恶化系统性能。该文提出了一种新的OFDM接收机PHN估计和抑制方法,利用判决数据采用Huber ML估计方法对PHN引起的ICI分量进行迭代估计,将估计的ICI系数变换到时域来校正每个样点的相位误差,从而达到抑制PHN的目的。与传统的基于判决的估计方法相比,该方法对判决的错误传播具有鲁棒性,可进一步提高ICI抑制性能。对算法在AWGN和多径信道环境下的仿真结果表明所提方法对PHN引起的ICI有较好的抑制性能。

One of the main drawbacks of OFDM is its high sensitivity to phase noise （PHN）. This gives rise to subcarriers phase rotation and InterCarrier Interference （ICI）, so the orthogonality of subcarriers is destroyed. In this paper, an iterative PHN mitigation method is proposed. ICI coefficients axe estimated in frequency domain by Huber ML estimator, and phase errors axe mitigated in time domain samples by samples. The Huber ML estimator is robust to the propagation errors. Simulation results are reported in AWGN and multi-path channel models, which shows that the superior ICI mitigation performance of the proposed algorithm is achieved over the other available PHN mitigation methods.