摘要
基于阈值的小波域非线性滤波的核心步骤是阈值的选取 .硬阈值t=cσ被证明是很有效的 ,但一般来说最佳的参数c会随信号的不同和迭加噪声的强度而变化 .本文构造了一个信号MSE(均方差 )函数的近似函数 ,以此做为阈值参数c选取的一种依据 .通过计算不同c下该函数的值 ,来判断使该函数最小的阈值参数c.仿真结果表明了真实MSE函数与本文提出的近似函数的一致性 。
The hard threshold t=cσ is proved to be efficient in threshold based nonlinear filtering by wavelet transform.Generally speaking,the optimal c varies with the signals and the intension of the added noise.Here we construct a function that approximates an equivalent function of the MSE of the recovered signal.The approximate optimal c can be determined by minimizing the function.Simulations show that the function we construct is consistent with the MSE of the filtered signal and the so selected c is reasonable.
出处
《电子学报》
EI
CAS
CSCD
北大核心
2001年第3期400-402,共3页
Acta Electronica Sinica
基金
"跨世纪优秀人才培养计划"基金!(教计函 [2 0 0 0 ] 1号 )
