中文摘要：

小掠射角声波照射下的掩埋物体散射声场计算,对水声探测系统的设计十分重要。现有基于声线理论的方法,无法计算小掠射角声波照射下的掩埋物体散射声场。基于波数积分声场模型和虚源方法,开发了可计算海底掩埋物体三维散射声场的模型软件。通过引入等效目标强度的定义,仿真计算了掩埋圆台和球壳的等效目标强度和回声信混比,并分析了掩埋深度和声波掠射角对信混比的影响。结果表明,用单基地方式工作时,掩埋物体的回声信混比总是很小,探测十分困难,若采用双基地探测,当掩埋深度达到30cm时,信混比可提高40dB以上,对掩埋物体探测系统的设计具有参考价值。

英文摘要：

The calculation of the scattering field from the buried targets, which is insonified by the acoustic wave with low grazing angle, is very important for designing a detection system. However, the scattering field from a buried target can not be obtained using the methods based on the ray model. Combining the wavenumber integral model and virtual source method, a software for 3D scattering field from the buried target was developed. Introducing the definition of effective target strength, the target strength and echo-to-reverberation ratio of buried conical frustum and spherical shell were computed. The effects of buried depth and incident grazing angle were analyzed. The results show that the echo-to-reverberation is always very low so that it is very difficult to detect with the monostatic mode. The simulation shows that if the bistatic detection mode is applied, the echo-to-reverberation ratio is improved above 40dB when the target is buried under 30cm below the bottom surface. The simulation results are useful for real application.