MIMO PLC系统中脉冲噪声消除方法

电力线通信(power line communication， PLC)中，脉冲噪声严重影响通信的可靠性，如何有效消除脉冲噪声对系统的影响是目前电力线通信急需解决的问题。提出一种在多输入多输出(multiple-input multiple-output， MIMO)PLC系统中脉冲噪声消除方法，在时域通过设置最优阈值对高幅度脉冲噪声进行置零。在频域通过迭代法结合空频分组码(space frequency block code， SFBC)消除低幅度脉冲噪声，该步骤是先进行硬判决检测，利用空频分组码空间和频域的分集增益，检测出可靠性更高的符号；用频域的接收信号减去重构的经过信道的信号来重构出剩余的脉冲噪声；在时域减去剩余的脉冲噪声，1次迭代过程完成。经过1次迭代后已经消除部分脉冲噪声，多次迭代则系统性能将明显提升。仿真结果表明，该算法相比传统的脉冲噪声消除算法性能提升了1.46 dB，使脉冲噪声对系统性能的影响明显减小。

Impulse noise mitigation method in MIMO PLC system

In the power line communication(PLC), the impulse noise seriously affects the reliability of the communication. The effective method to eliminate the influence of impulse noise on the system is the urgent issue to be solved in PLC. In this paper, we propose a method to eliminate the impulse noise in multiple input multiple output (MIMO) PLC systems. By setting the optimal threshold in the time domain, the high amplitude impulse noise is set to zero. In the frequency domain, the residual impulse noise is eliminated by the iterative method combined with the space frequency block coding(SFBC), this step uses the gain of SFBC space and frequency domain to detect the more reliable symbols. Then the reconstructed channel passing signal is subtracted from the received signal in the frequency domain to reconstruct the remaining impulse noise. Finally, after the remaining impulse noise is subtracted in the time domain, an iterative process is completed. After several iterations, the system performance will be significantly improved.The simulation results show that the performance of the algorithm is 1.46 dB higher than that of the traditional impulse noise cancellation algorithm, and it significantly reduces the effect of impulse noise to the performance of the system.