Theoretical analysis and experimental results of interference striation pattern of underwater target radiated noise in shallow water waveguide  

作　　者：LI Qihu WANG Lei WEI Chonghua LI Yi MA Xuejie YU Haichun 

机构地区：[1]Institute of Acoustics, Chinese Academy of Sciences Beijing 100190

出　　处：《Chinese Journal of Acoustics》2011年第1期73-80,共8页声学学报（英文版）

摘　　要：Waveguide invariant in shallow water is an attractive topic in recent three decades. The interference phenomena of direct wave of radiated noise of underwater target and reflection wave from sea surface and sea bottom can be considered as a typical case of shallow water waveguide. The interference striation pattern of direct wave and its reflection is the effective and comprehensive figure for better understanding the essence of shallow water waveguide invariant. The theoretical analysis of interference phenomena generated by direct wave of radiated noise of underwater target and its reflection wave from sea surface and sea bottom is presented in this paper. It is shown that the interference wave resulted by sea surface reflection will produce striation pattern centered at high frequency band. But the interference of nulling frequency resulted by sea bottom reflection may be at low frequency or high frequency, it strongly depends on the acoustic behavior of sea bottom. The relationship between main parameters of interference striation pattern and target, receiver, and environment is derived. It is shown that the interference striation have the shape of hyperbolic curve. The equation set of the hyperbolic curve and its asymptotic line is presented. The at sea experiment carried out in South China sea shows some interesting results. A part of data processing results are illustrated in this paper. The results expressed in this paper show that the interference striation pattern can be used, in some conditions, as a potential means for target recognition.Waveguide invariant in shallow water is an attractive topic in recent three decades. The interference phenomena of direct wave of radiated noise of underwater target and reflection wave from sea surface and sea bottom can be considered as a typical case of shallow water waveguide. The interference striation pattern of direct wave and its reflection is the effective and comprehensive figure for better understanding the essence of shallow water waveguide invariant. The theoretical analysis of interference phenomena generated by direct wave of radiated noise of underwater target and its reflection wave from sea surface and sea bottom is presented in this paper. It is shown that the interference wave resulted by sea surface reflection will produce striation pattern centered at high frequency band. But the interference of nulling frequency resulted by sea bottom reflection may be at low frequency or high frequency, it strongly depends on the acoustic behavior of sea bottom. The relationship between main parameters of interference striation pattern and target, receiver, and environment is derived. It is shown that the interference striation have the shape of hyperbolic curve. The equation set of the hyperbolic curve and its asymptotic line is presented. The at sea experiment carried out in South China sea shows some interesting results. A part of data processing results are illustrated in this paper. The results expressed in this paper show that the interference striation pattern can be used, in some conditions, as a potential means for target recognition.

分 类 号：O436.1[机械工程—光学工程] TB56[理学—光学]