基于小波变换的水下连续爆炸声信号特征分析

Analysis of characteristics of sequential underwater explosion sound signal based on wavelet transform

为了研究水下连续爆炸声信号的特征,利用Mallat算法,采用离散小波变换对水下连续爆炸声信号进行了分层提取分析,讨论了水下连续爆炸声信号在各频带的能量分布状况,采用Welch方法实现了对水下连续爆炸声信号的功率谱特征提取,并采用离散小波变换对声信号进行时频谱特性分析。结果表明,水下连续爆炸声信号具有很强的声功率,声压级可以达到190dB以上,声持续时间较长,频率范围宽、声信号的能量主要集中在频率48kHz以下,其中在低频段能量更大,这些特点使其有望成为水声干扰源。

To obtain the characteristics of sequential underwater explosion sound signals effectively, the sequential underwater explosion sound signals have been gradually extracted by the Mallat algo-rithm of wavelet transform. The energy distribution of the sequential underwater explosion sound signal at different frequency ranges was discussed by adopting the discrete wavelet transform. The Welch spectrum method had been used to extract the power spectrum characteristics of sequential underwater explosion sound signals. The time-frequency characteristic was analyzed by using the discrete wavelet transform. The results show that the sequential underwater explosion has characteristics of strong sound power, longer sound duration and wide frequency range, the sound pressure level can be more than 190 dB, the energy is mainly concentrated in area of 48 kHz, with the higher energy band in the low frequency band. These characteristics show that the sequential underwater explosion can be used as a source of sound interference. The results also show that wavelet transform can be used to study the characteristics of the sequential underwater explosion sound signals reasonably so as to analyze them accurately.