基于小波变换选择的海底沉积物声速分析技术

Wavelet Transfer on Seafloor Sediment Acoustic Measurement

海底沉积物物理特性参数的研究对海洋资源开发、海底工程建设、海地测绘、海洋灾害预报、海底历史研究、航运国防等具有重要意义。它可由对出海采样的样品直接进行土工实验获取,或者经测量得到的声学特性参数表征。目前海底沉积物探测主要以声学测量为主,通过接收透射、反射、折射的声波后提取出声学特性而成,包括压缩波速、切变波速(液体不存在)、声波阻抗、声衰减。针对传统的走时法由于人工读取起跳点造成声速的精确度不高这一特点,引出小波分析方法读取起跳点,应用小波分解原始信号得到的细节信号的模极大值连线来确定原始信号的畸变点,从而确定为接收声信号的起跳点以计算声速。

The study of seafloor sediment physical parameters contributes to marine resources development, underwater engineering construction, seafloor mapping, marine disaster forecasting, submarine history, shipping, national defense etc. It may be acquired di- rectly, or characterized by ultrasound measurements of the acoustic parameters. At present ultrasound measurement is the main method for seafloor sediment inspection, by receiving transmission, reflection and refraction of the acoustic properties, such as com- pression wave velocity, shear wave velocity （liquid not included）, acoustic impedance, sound attenuation. Aiming at the traditional path of take-off point with lower precision, the wavelet analysis is introduced to get the take-off point. Wavelet decomposition of the original signal is applied to determine acoustic velocity by the maximum line of connection in the details.