动态目标(群)宽带电磁特性精确建模理论与关键技术研究

The accurate simulation of moving target's scattering characteristics is the key research topic in the field of computational electromagnetics and target detection, which has great significance in scientific research and applications. This project tries to use Time Domain Integral Equation(TDIE) with Marching on-in Time method based on high order geometry model and high order basis functions to simulate the wideband electromagnetic scattering characteristic of both single moving target and group moving targets with high efficiency. Furthermore, the moving effect on the target's scattering characteristic is studied by the proposed method. Firstly, the accurate method of evaluating time-domain impedance matrix based on high order geometry model and high order bases is studied for achieving accurate and stable solution of static target. After that, two methods are combinied to accurately simulate the wideband electromagnetic scattering of single target with complex moving. They are, the quasi-static method applied in low-speed problem and the TDIE-MOT combined with Lorenze Transformation applied in fast moving, respectively. Finally, the Domain Decomposition Method in TDIE is applied to solve the scattering problem of group moving targets with relative moving. In this part, the dynamic coupling equation between sub-targets in space and time domain is studied and the corresponding marching on-in time and space domain is established. Finally, the wideband electromagnetic characteristic of group moving targets with relative moving is achieved accurately and efficiently.

动态目标的电磁散射特性精确数值模拟方法是电磁场数值分析及目标特性领域亟待深入研究的课题，既具有重要的科学意义和学术价值,也具有实际工程应用前景。本项目拟利用基于高阶几何建模和高阶基函数的时域积分方程(TDIE)时间步进算法精确高效地模拟动态目标及动态目标群的宽带电磁散射，并分析运动效应对目标散射特性的影响。 首先，研究基于高阶几何建模和高阶基函数的时域阻抗矩阵精确计算方法，实现静止目标时域积分方程的精确稳定时间步进法求解；然后，利用低速微动的准静态法与高速平动的时域积分方程法的混合算法精确快速模拟具有复杂运动的单目标宽带电磁散射；最后，利用时域积分方程中的区域分解算法求解具有相对运动的动态目标群宽带电磁散射问题，研究各子目标在空间与时间上的动态场耦合方程，建立对应的空域与时域联合步进格式，实现动态目标群宽带电磁特性的精确高效求解。

动态目标的电磁散射特性精确数值模拟方法是电磁场数值分析及目标特性领域亟待深入研究的课题，具有重要的科学意义和实际工程价值。本项目基于高阶几何建模和高阶基函数的时域积分方程(TDIE)时间步进算法实现了动态目标及动态目标群宽带电磁散射的精确高效仿真计算。 首先，研究了基于高阶几何建模和高阶基函数的时域阻抗矩阵精确计算方法，实现静止目标时域积分方程的精确稳定时间步进法求解；然后，利用低速微动的准静态法与高速平动的时域积分方程法的混合算法精确快速模拟具有复杂运动的单目标宽带电磁散射；其次，利用时域积分方程中的区域分解算法求解具有相对运动的动态目标群宽带电磁散射问题，研究各子目标在空间与时间上的动态场耦合方程，建立对应的空域与时域联合步进格式，实现动态目标群宽带电磁特性的精确高效求解；最后，结合分层介质格林函数，研究了半空间与分层介质背景环境下的电磁散射特征，对半空间环境下的动态目标电磁特性分析进行了初步探讨。该技术有望用于目标特征与雷达信号分析领域，项目的研究对我国雷达及相关领域的发展具有重要意义。