作　　者： ; ; ;

机构地区： 复旦大学信息科学与工程学院电子工程系

出　　处： 《大连海事大学学报》 2009年第2期47-50,共4页

摘　　要： 为解决脉冲噪声下最小均方误差自适应时间延迟估计算法估计性能的退化问题,以对称α稳定分布模型描述脉冲噪声,提出最小均方Sigmoid误差自适应时间延迟估计算法.该算法通过对误差信号求取Sigmoid变换,抑制了较大误差对估计结果的影响.以最小均方Sigmoid误差代替最小均方误差作为优化准则,迭代模拟信道延迟效应的滤波器权系数,其收敛时峰值的位置就是所要估计的时间延迟.仿真结果验证了该算法在高斯和非高斯对称α稳定分布噪声条件下的优良估计性能,说明最小均方Sigmoid误差是一种韧性的最优准则. To solve the degradation of the least mean square adaptive time delay estimation （TDE） algorithm with the presence of impulsive noises, a adaptive TDE approach （LMSSETDE） was developed based on the least mean square Sigmoid error （LMSSE） since impulsive noises in the application may usually be modeled as the symmetric α-table distribution. The error signal was transformed by the Sigmoid function, so the effect of outliers on the estimation result was restrained and the second moment of transformed error signal existed. Under the LMSSE criteria, weight coefficient vectors of the filter which simulating the delay effect of channels, were iterated and the peak location of weight coefficients after the convergence was regarded as the relative time delay between two received signals. Simulation results show that the estimation performance of the LMSSETDE algorithm is excellent under Gaussian and non-Gaussian symmetric s-stable distribution noises. Therefore, the least mean square Sigmoid error is a kind of robust optimal criteria.

关 键 词： 时间延迟估计 最小均方 误差 脉冲噪声 对称 稳定分布 自适应滤波器

领　　域： [电子电信] [电子电信]