基于表面波变换的水声瞬态信号降噪方法

Denoising method for underwater acoustic transient signals based on surfacelet transform

为提高对水下目标信号检测的有效性和可靠性,对水声基阵信号的干扰噪声进行分析,提出对含噪信号进行三维表面波变换的降噪方法.通过设置适当的阈值,对变换后的系数进行舍取处理,得到表征信号及微量残余噪声的重构系数;对其进行表面波逆变换后得到降噪后的水声基阵信号.对实际水声信号的降噪实验表明:该方法实现了对基阵信号的并行处理,取得了较好的降噪效果.

3D surfacelet transform-based denoising method for noisy signal was developed to improve the validity and reliability of underwater transient signals detection. The interference noise in underwater acoustic array signal was analyzed, and the surfacelet reconstruction coefficients of characterized signal and weak residual noise were obtained by searching out the required transformed coefficients which were above set appropriate threshold. The denoised acoustic array signals were obtained by surfacelet inverse transformation for transformed coefficients. Tests on acoustic signal denoising show that the proposed method can realize the parallel calculations for array signals, and the denoising effect is satisfactory.