水声通信系统中基于迭代自适应的脉冲噪声抑制方法

摘要

针对水声通信系统中脉冲噪声抑制问题,提出了一种迭代自适应的脉冲噪声抑制方法.基于OFDM子载波之间的正交性,该方法首先利用空子载波矩阵从接收信号中提取出背景噪声和脉冲噪声.然后,利用空子载波矩阵构造导频矩阵,得到脉冲噪声的干扰协方差矩阵,并在加权最小二乘准则下通过对代价函数的求解得到脉冲噪声的闭式解.最后,在接收信号中减去脉冲噪声的估计值,完成对脉冲噪声的抑制.仿真结果表明,本文方法有效降低了水声通信系统的误码率,且在高信干噪比下性能提升更加明显.%Focusing on the impulsive noise mitigation in underwater acoustic communication,an impulsive noise mitigation method based on iteration adaptive approach was proposed.Firstly,by utilizing the orthogonality of the subcarriers in OFDM system,both the impulsive noise and background noise were separated from the signals.Then null tones matrix was used to construct a steering matrix and get the impulsive noise interference covariance matrix.Furthermore,a cost function based on weighted least squares approach was proposed and a close form expression for the impulsive noise was derived.Finally,the impulsive noise was mitigated by substracting the estimation of the impulse noise in the received signal.Simulation results show that the proposed algorithm can reduce the bit error rate (BER) efficiently and provide better performance,especially in high signal to impulsive noise ratio (SINR) case.