【摘要】 基于时域有限差分（FDTD）方法对实际地形与上方目标的复合宽带电磁散射特性进行了研究。应用数字高程模型（DEM）表示实际地形表面、Dobson模型表示土壤的介电常数，利用FDTD方法计算了宽带波入射于实际地形与上方目标时的频率响应曲线，得到了入射角、土壤温度、土壤体积含水量、目标底部所处高度的变化对复合宽带电磁散射系数的影响。结果表明，复合散射系数随频率振荡地变化，复合散射系数幅度随土壤体积含水量和目标底部所处高度的增大而减小、随着土壤温度和入射角度增加而逐渐增大，其他规律比较复杂，并无固定的规律可循。研究结果对理解实际粗糙地面的宽带散射特性具有一定价值，并可应用于无线通信、目标探测等领域的系统设计和优化。更多还原

【Abstract】 The composite broadband electromagnetic scattering characteristics of actual terrain and the target above it were studied based on the Finite-Difference Time-Domain(FDTD) method. The Digital Elevation Model(DEM) was used to represent the actual terrain surface, and the Dobson model was applied to describe the dielectric constant of the soil. The FDTD method was applied to calculate the frequency response curves of broadband waves incident on the actual terrain and the target overhead. The influence of the incident angle, soil temperature, soil volumetric water content, and the height of target movement on the composite broadband electromagnetic scattering coefficient were obtained. The results show that the composite scattering coefficient varies oscillatingly with frequency.The amplitude of the composite scattering coefficient decreases with the increase of soil volumetric water content and the height of the target base, and gradually increases with the increase of soil temperature and incident angle. Other patterns are relatively complex and do not follow a fixed rule. These research results have certain value for understanding the broadband scattering characteristics of actual rough ground and can be applied to the system design and optimization in fields such as wireless communication and target detection.更多还原