卷浪是‘海尖峰’现象产生的主要原因之一，‘海尖峰’信号与目标信号相似，对海上低空目标的探测和识别造成直接影响。鉴于复杂海洋环境中下视雷达对海上低空目标探测和识别的迫切需求，本项目拟通过电磁理论建模的途径开展三维含卷浪复杂海面上方低空目标复合电磁散射特性及耦合机理研究。具体包括：采用SBR/PTD、积分方程法以及多路径思想分别求解低空目标散射、含卷浪海面散射以及目标与含卷浪海面之间的耦合散射，并结合GPU和CUDA并行加速技术，建立三维含卷浪复杂海面上方低空目标复合电磁散射模型；探索卷浪几何形态以及目标姿态角对耦合散射的影响，分析含卷浪海面上方低空目标复合散射随雷达参数、海况参数、卷浪几何形态、目标高度以及姿态角等因素的变化规律，揭示含卷浪海面与低空目标之间复杂的电磁耦合机理，旨在为含卷浪海面上方低空目标的探测、识别以及雷达成像等提供一定的理论依据和技术支持。

The overturning wave crest is considered as one of the main reasons to the sea-spike phenomenon. The signals of sea spikes are similar to those of target, which has a great influence on the detection and recognition of low-altitude target above the sea surface. As a result of the urgent demands of the look-down radar in the complex marine environment for the detection and recognition of low-altitude target, this project will focus on the investigation of composite scattering characteristics and coupling mechanism of the low-altitude target above three-dimensional complex sea surface with overturning wave crest by the electromagnetic modeling. The SBR/PTD method, Integral Equation Model and the multipath thought are utilized to compute the scattering of low-altitude target and sea surface with overturning wave crest as well as the coupling scattering between the target and sea surface with overturning wave crest, respectively. Then the GPU and CUDA parallel acceleration techniques are adopted to further improve the simulation efficiency, and the composite scattering model is established. The influence of overturning wave crest's profile and target's altitude angle on the coupling scattering is investigated, and the variation of composite scattering with the radar parameters, ocean condition, profile of overturning wave crest as well as the height and altitude angle of target will be analyzed, revealing the complicated coupling mechanism between the low-altitude target and sea surface with overturning wave crest. This project will provide a theoretical foundation and technical support for the detection and recognition of low-altitude target above sea surface with overturning wave crest as well as radar imaging, etc.