A novel high-order three-dimensional （3-D） discontinuous Galerkin time domain （DGTD） method based on a normalized formulation of Maxwell＇s equations is developed for modeling and simulating silicon-on-insulator ...A novel high-order three-dimensional （3-D） discontinuous Galerkin time domain （DGTD） method based on a normalized formulation of Maxwell＇s equations is developed for modeling and simulating silicon-on-insulator （SOD thin-ridge waveguide. The DGTD method employs unstructured meshes and piecewise high-order polynomials for spatial discretization, and Runge-Kutta methods for time integration. It is found that the numerical results of the leakage loss of SOI thin-ridge waveguide agree well with those of analytical solutions, which proves that the proposed method is an ideal tool for the quantitative analysis for SOI thin-ridge waveguide.展开更多
Several major challenges need to be faced for efficient transient multiscale electromagnetic simulations, such as flex- ible and robust geometric modeling schemes, efficient and stable time-stepping algorithms, etc. F...Several major challenges need to be faced for efficient transient multiscale electromagnetic simulations, such as flex- ible and robust geometric modeling schemes, efficient and stable time-stepping algorithms, etc. Fortunately, because of the versatile choices of spatial discretization and temporal integration, a discontinuous Galerkin time-domain （DGTD） method can be a very promising method of solving transient multiscale electromagnetic problems. In this paper, we present the application of a leap-frog DGTD method to the analyzing of the multiscale electromagnetic scattering problems. The uniaxial perfect matching layer （UPML） truncation of the computational domain is discussed and formulated in the leap-frog DGTD context. Numerical validations are performed in the challenging test cases demonstrating the accuracy and effectiveness of the method in solving transient multiscale electromagnetic problems compared with those of other numerical methods.展开更多
时域离散伽辽金法(Discontinuous Galerkin Time Domain,DGTD)同时具有时域有限元算法(Finite Element Time Domain,FETD)非结构网格剖分和时域有限差分算法(Finite Difference Time Domain,FDTD)显式迭代的优点,是一种非常有前途的电...时域离散伽辽金法(Discontinuous Galerkin Time Domain,DGTD)同时具有时域有限元算法(Finite Element Time Domain,FETD)非结构网格剖分和时域有限差分算法(Finite Difference Time Domain,FDTD)显式迭代的优点,是一种非常有前途的电磁计算方法,该文首先描述了基于矢量基函数的时域离散伽辽金法的基本原理。然后,给出了DGTD处理散射问题时平面波入射加入的具体实现方法。最后,给出了金属球、介质球和金属弹头宽带散射的算例,算例结果的比较表明了该文算法的正确性和有效性。该文的研究,为复杂目标雷达散射截面RCS的准确预估打下了坚实的基础。展开更多
给出了时域非连续伽辽金(Discontinuous Galerkin Time Domain,DGTD)法的基本思想,从Maxwell方程出发得到弱解形式和矩阵方程,进一步给出了DGTD步进计算式.计算了空腔和填充谐振腔的谐振频率,并与解析结果相比较.算例表明在谐振腔计算中...给出了时域非连续伽辽金(Discontinuous Galerkin Time Domain,DGTD)法的基本思想,从Maxwell方程出发得到弱解形式和矩阵方程,进一步给出了DGTD步进计算式.计算了空腔和填充谐振腔的谐振频率,并与解析结果相比较.算例表明在谐振腔计算中DGTD可以达到很高的精度.展开更多
电磁场时域计算方法由于一次计算可以获得目标的时域响应,结合傅里叶变换得到宽带信息等的优势越来越受到关注.本文介绍了近年来时域有限差分(finite-difference time-domain,FDTD)法和时域有限元(finite element time-domain,FETD)无...电磁场时域计算方法由于一次计算可以获得目标的时域响应,结合傅里叶变换得到宽带信息等的优势越来越受到关注.本文介绍了近年来时域有限差分(finite-difference time-domain,FDTD)法和时域有限元(finite element time-domain,FETD)无条件稳定算法方面的研究进展以及FETD算法的更新方案--时域非连续伽辽金(discontinuous Galerkin time-domain,DGTD)方法的新进展.展开更多
以氮化镓(GaN)为代表的第三代半导体正促使着固态微波功率器件向着更高功率、更高效率、集成化的方向不断发展,但这会导致器件内部电磁场分布效应更为显著,单一的路仿真已无法满足分析设计的精度需求,亟需建立有源GaN器件与无源电磁结...以氮化镓(GaN)为代表的第三代半导体正促使着固态微波功率器件向着更高功率、更高效率、集成化的方向不断发展,但这会导致器件内部电磁场分布效应更为显著,单一的路仿真已无法满足分析设计的精度需求,亟需建立有源GaN器件与无源电磁结构的一体化协同仿真技术.针对这一需求,本文提出基于时域不连续伽辽金技术的GaN基高功率微波器件高效场路协同仿真方法,将所提取的GaN HEMT(high electron mobility transistor)器件大信号紧凑模型引入电磁场方程中,采用局部时间步进技术以消除非线性紧凑模型及多尺度网格对全局算法稳定性条件的限制,实现有源器件-无源电磁结构、多尺度粗细网格的高效自适应求解.通过数值仿真算例与实验测试及软件计算结果对比展示了本文所提方法准确性和高效性,可为先进大功率微波器件的高可靠研发提供理论基础与设计参考.展开更多
基金Supported by the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘A novel high-order three-dimensional （3-D） discontinuous Galerkin time domain （DGTD） method based on a normalized formulation of Maxwell＇s equations is developed for modeling and simulating silicon-on-insulator （SOD thin-ridge waveguide. The DGTD method employs unstructured meshes and piecewise high-order polynomials for spatial discretization, and Runge-Kutta methods for time integration. It is found that the numerical results of the leakage loss of SOI thin-ridge waveguide agree well with those of analytical solutions, which proves that the proposed method is an ideal tool for the quantitative analysis for SOI thin-ridge waveguide.
基金supported by the National Natural Science Foundation of China(Grant Nos.61301056 and 11176007)the Sichuan Provincial Science and Technology Support Program,China(Grant No.2013HH0047)+1 种基金the Fok Ying Tung Education Foundation,China(Grant No.141062)the"111"Project,China(Grant No.B07046)
文摘Several major challenges need to be faced for efficient transient multiscale electromagnetic simulations, such as flex- ible and robust geometric modeling schemes, efficient and stable time-stepping algorithms, etc. Fortunately, because of the versatile choices of spatial discretization and temporal integration, a discontinuous Galerkin time-domain （DGTD） method can be a very promising method of solving transient multiscale electromagnetic problems. In this paper, we present the application of a leap-frog DGTD method to the analyzing of the multiscale electromagnetic scattering problems. The uniaxial perfect matching layer （UPML） truncation of the computational domain is discussed and formulated in the leap-frog DGTD context. Numerical validations are performed in the challenging test cases demonstrating the accuracy and effectiveness of the method in solving transient multiscale electromagnetic problems compared with those of other numerical methods.
文摘时域离散伽辽金法(Discontinuous Galerkin Time Domain,DGTD)同时具有时域有限元算法(Finite Element Time Domain,FETD)非结构网格剖分和时域有限差分算法(Finite Difference Time Domain,FDTD)显式迭代的优点,是一种非常有前途的电磁计算方法,该文首先描述了基于矢量基函数的时域离散伽辽金法的基本原理。然后,给出了DGTD处理散射问题时平面波入射加入的具体实现方法。最后,给出了金属球、介质球和金属弹头宽带散射的算例,算例结果的比较表明了该文算法的正确性和有效性。该文的研究,为复杂目标雷达散射截面RCS的准确预估打下了坚实的基础。
文摘给出了时域非连续伽辽金(Discontinuous Galerkin Time Domain,DGTD)法的基本思想,从Maxwell方程出发得到弱解形式和矩阵方程,进一步给出了DGTD步进计算式.计算了空腔和填充谐振腔的谐振频率,并与解析结果相比较.算例表明在谐振腔计算中DGTD可以达到很高的精度.
文摘对高速信号通过电源板时的电源完整性(power integrity,PI)问题进行研究时,因为电源板中主要模式分布为零阶平行板模式,可以采用二维简化以提高效率.而对于隔离盘或其它存在纵向不连续性的区域,则应采用三维算法以保证精度.将两者结合起来的一种二维三维(2D/3D)混合时域不连续伽辽金(discontinuous Galerkin time domain,DGTD)方法可以兼顾精度与效率,有效地处理这类电磁全波计算问题.其中二维、三维方法采用同一套三棱柱离散的网格,通过适当设置基函数,二维区域与二维区域之间可以方便快速地相互转化.随着电磁波的传播,二维、三维的适用区域是随时间、空间动态变化的.为了准确地捕捉这种动态变化,文中提出的一种改进的自适应判据,在每个时间歩对电磁场进行检测,从而动态地判定二维简化区域.与现有技术的判据控制绝对误差不同,该方法对相对误差进行控制,效率高、精度好,对于不同的结构适应性强.通过数值实验,与商业软件和全三维(3D)DGTD方法的结果进行了比较和验证.
文摘以氮化镓(GaN)为代表的第三代半导体正促使着固态微波功率器件向着更高功率、更高效率、集成化的方向不断发展,但这会导致器件内部电磁场分布效应更为显著,单一的路仿真已无法满足分析设计的精度需求,亟需建立有源GaN器件与无源电磁结构的一体化协同仿真技术.针对这一需求,本文提出基于时域不连续伽辽金技术的GaN基高功率微波器件高效场路协同仿真方法,将所提取的GaN HEMT(high electron mobility transistor)器件大信号紧凑模型引入电磁场方程中,采用局部时间步进技术以消除非线性紧凑模型及多尺度网格对全局算法稳定性条件的限制,实现有源器件-无源电磁结构、多尺度粗细网格的高效自适应求解.通过数值仿真算例与实验测试及软件计算结果对比展示了本文所提方法准确性和高效性,可为先进大功率微波器件的高可靠研发提供理论基础与设计参考.
