一种改进的电力线通信系统脉冲噪声抑制方法

为了抑制脉冲噪声对电力线正交频分复用（OFDM）通信系统的影响，最常用的方法之一是在接收端OFDM解调器之前前置一个置零非线性单元，即传统置零法。然而，由于引入了非线性失真，其性能并不理想。针对传统置零法引起的非线性失真问题，提出了一种基于迭代消除非线性失真的改进置零法。首先，对接收到的时域OFDM信号进行脉冲噪声检测和置零处理；然后，在频域利用已检测的符号来重构时域置零处理引入的非线性失真，并通过迭代提高重构的准确性；最后，从频域接收信号中减去重构的非线性失真。仿真结果表明，所提改进算法与传统置零法相比，有非常大的性能提升，增强了电力线OFDM通信系统对脉冲噪声的抵抗能力。

An improved impulsive noise suppression method for power line communication systems

In order to suppress the influence of impulsive noise on power line orthogonal frequency division multiplexing(OFDM) communication system,one of the most commonly used methods is to preset a blanking nonlinearity unit before the OFDM demodulator,that is,traditional blanking method. However,the performance of this method is not satisfactory because of the introduction of nonlinear distortion. For the nonlinear distortion problem introduced by traditional blanking method,an improved blanking method based on iterative elimination of nonlinear distortion is proposed. Firstly,impulsive noise detection and nulling of the received time domain OFDM signal are carried out. Then,the nonlinear distortion introduced by the time domain zero setting processing is reconstructed by using the detected symbols in the frequency domain,and the accuracy of the reconstruction is improved by iteration. Finally,the reconstructed nonlinear distortion is subtracted from the frequency domain received signal. The simulation results show that the proposed algorithm has significant performance improvement compared with the traditional blanking method,and enhances the resistance of the power line OFDM system to impulsive noise.