摘要
本文针对温度差异对沉积物的声学特性的影响,研究不同温度下沉积物的频谱特征规律。把南海深海沉积物的人工样品置于温控环境中,采集经历沉积物的超声信号,对其进行快速傅里叶变换获得频谱特征,分别从主频漂移、主频幅值、主频频宽、接收能量等方面归纳出温度影响下的海底沉积物超声信号的频谱特征规律:如温度变化影响频谱特征,但可重复性低;温度增加使沉积物对声信号的衰减增大;频宽与频率幅值呈负相关,但温度-幅值的关系明显于温度-频宽的关系。因此,温度改变导致沉积物超声信号频谱的规律性变化。
Temperature, salinity, and pressure are the three effectors of marine sediment＇s physical, mechanical and acoustic properties. The authors focus on the effect of temperature perturbation on seafloor sediment, and study the spectrum Characteristics. They use the sediment remainder of the South China Sea, make artificial samples and then place them in a temperature-controlled environment, measure the sediment acoustic signals, and finally obtain the sediment＇s spectrum characteristics by fast Fourier transform. The characteristics of temperature perturbation can be described by frequency drift, frequency amplitude, frequency bandwidth, and energy reception, respectively. For example, temperature contributes to the seafloor sediment＇s spectrum regularity, with low repeatability; temperature increase enhances acoustic signal attenuation; frequency bandwidth and amplitude are negatively correlated, but the correlation of thermal-amplify is much clearer than thermal-bandwidth. The experiment suggests that the frequency in different temperature distinguishes the acoustics spectrum.
出处
《热带海洋学报》
CAS
CSCD
北大核心
2009年第4期79-86,共8页
Journal of Tropical Oceanography
基金
国家自然科学基金项目(40876018)
中国科学院声场声信息国家重点实验室研究课题(200801)
关键词
海底沉积物
声学测量
幅值谱
主频
频宽
seafloor sediment
acoustics
spectrum
primary frequency
bandwidth
